Fluke RPM4 User Manual

RPM4™  
Reference Pressure Monitor  
Operation and Maintenance Manual  
© 2004-2007 DH Instruments, a Fluke Company  
TABLE OF CONTENTS  
TABLE OF CONTENTS  
TABLE OF CONTENTS ............................................................... I  
TABLES .................................................................................. V  
FIGURES................................................................................ VI  
ABOUT THIS MANUAL ............................................................ VII  
1. INTRODUCTION ................................................................. 1  
1.1  
1.2  
PRODUCT OVERVIEW ...........................................................................................................................1  
SPECIFICATIONS ...................................................................................................................................2  
1.2.1  
GENERAL SPECIFICATIONS.......................................................................................................................2  
PRESSURE MEASUREMENT SPECIFICATIONS........................................................................................2  
QUARTZ REFERENCE PRESSURE TRANSDUCER (Q-RPT) ................................................................2  
ON-BOARD BAROMETER ........................................................................................................................4  
BATTERY AND CHARGER PACK................................................................................................................5  
1.2.2  
1.2.2.1  
1.2.2.2  
1.2.3  
2. INSTALLATION .................................................................. 7  
2.1  
UNPACKING AND INSPECTION ............................................................................................................7  
2.1.1  
2.1.2  
REMOVING FROM PACKAGING..................................................................................................................7  
INSPECTING CONTENTS.............................................................................................................................7  
2.2  
2.3  
SITE REQUIREMENTS............................................................................................................................8  
SETUP .....................................................................................................................................................8  
2.3.1  
PREPARING FOR OPERATION ...................................................................................................................8  
FRONT AND REAR PANELS........................................................................................................................8  
FRONT PANEL ..........................................................................................................................................8  
REAR PANEL.............................................................................................................................................9  
POWER CONNECTION.................................................................................................................................9  
85 TO 264 VAC, 50/60 HZ VAC POWER ..................................................................................................9  
BATTERY PACK ........................................................................................................................................9  
REMOTE [ENT] CONNECTION (FOOTSWITCH OR OTHER SWITCH)....................................................10  
CONNECTING TO MEASURE PRESSURE (TEST(+) AND TEST(-) PORTS)...........................................10  
THE VENT OR ATM PORT..........................................................................................................................11  
CHECK/SET SECURITY LEVEL.................................................................................................................11  
TURN OFF ABSOLUTE AND NEGATIVE GAUGE MODE (AXXX RPT)....................................................12  
SDS FULL TIME OFF ..................................................................................................................................12  
PARALLEL MEASUREMENT MODE..........................................................................................................12  
2.3.2  
2.3.2.1  
2.3.2.2  
2.3.3  
2.3.3.1  
2.3.3.2  
2.3.4  
2.3.5  
2.3.6  
2.3.7  
2.3.8  
2.3.9  
2.3.10  
2.4  
2.5  
POWER-UP AND VERIFICATION.........................................................................................................12  
2.4.1  
2.4.2  
2.4.2.1  
2.4.2.2  
SWITCH POWER ON ..................................................................................................................................12  
CHECK PRESSURE MEASUREMENT OPERATION.................................................................................13  
CHECKING ABSOLUTE MODE PRESSURE MEASUREMENT.............................................................13  
CHECKING GAUGE MODE PRESSURE MEASUREMENT...................................................................13  
SHORT TERM STORAGE.....................................................................................................................14  
3. OPERATION ..................................................................... 15  
3.1  
3.2  
USER INTERFACE................................................................................................................................15  
3.1.1  
3.1.2  
3.1.3  
3.1.4  
MAIN RUN SCREEN....................................................................................................................................15  
FUNCTION / DATA KEYPAD LAYOUT AND PROTOCOL.........................................................................17  
REMOTE [ENT] (ENTER) FOOTSWITCH...................................................................................................18  
SOUNDS ......................................................................................................................................................18  
GENERAL OPERATING PRINCIPLES .................................................................................................18  
3.2.1  
PRESSURE READY/NOT READY ..............................................................................................................18  
Page I  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
3.2.2  
GAUGE AND NEGATIVE GAUGE MODES WITH AN AXXX (ABSOLUTE) Q-RPT, DYNAMIC  
COMPENSATION FOR ATMOSPHERIC PRESSURE ...............................................................................19  
MULTIPE RANGES (Q-RPTS, AUTORANGE AND INFINITE RANGING) .................................................19  
PARALLEL MEASUREMENT MODE..........................................................................................................21  
USING RPM4 WITH A PPC3 CONTROLLER/CALIBRATOR.....................................................................21  
USE OF THE 12VDC BATTERY/CHARGER PACK ...................................................................................23  
SDS SELF DEFENSE SYSTEM ..................................................................................................................24  
DIRECT FUNCTION KEYS SUMMARY ......................................................................................................25  
3.2.3  
3.2.4  
3.2.5  
3.2.6  
3.2.7  
3.2.8  
3.3  
DIRECT FUNCTION KEYS....................................................................................................................25  
3.3.1  
[RANGE] ......................................................................................................................................................25  
[UNIT]...........................................................................................................................................................26  
[MODE] ........................................................................................................................................................27  
DIFFERENTIAL MEASUREMENT MODE OPERATION.........................................................................29  
[AUTORANGE] ............................................................................................................................................30  
[LEAK CK] ...................................................................................................................................................33  
[DISPLAY]....................................................................................................................................................34  
AVG (AVERAGE).....................................................................................................................................36  
RATE........................................................................................................................................................37  
DEV (DEVIATION) ...................................................................................................................................38  
RPT ..........................................................................................................................................................39  
HI/LO........................................................................................................................................................40  
FREEZE ...................................................................................................................................................41  
CLEAN .....................................................................................................................................................41  
[HEAD].........................................................................................................................................................42  
[SDS] (SELF DEFENSE SYSTEM) .............................................................................................................43  
SDS IN DIFFERENTIAL AND PARALLEL MEASUREMENT MODES....................................................46  
[AUTOZ].......................................................................................................................................................46  
[AUTOZ] IN GAUGE AND NEGATIVE GAUGE MODE ...........................................................................47  
[AUTOZ] IN ABSOLUTE MODE...............................................................................................................48  
AUTOZ IN DIFFERENTIAL MODE ..........................................................................................................51  
[ENT] (RUN AUTOTEST).............................................................................................................................51  
3.3.2  
3.3.3  
3.3.3.1  
3.3.4  
3.3.5  
3.3.6  
3.3.6.1  
3.3.6.2  
3.3.6.3  
3.3.6.4  
3.3.6.5  
3.3.6.6  
3.3.6.7  
3.3.7  
3.3.8  
3.3.8.1  
3.3.9  
3.3.9.1  
3.3.9.2  
3.3.9.3  
3.3.10  
3.4  
3.5  
[SETUP].................................................................................................................................................52  
3.4.1  
<1RANGE> ..................................................................................................................................................52  
SAVING AN AUTORANGE RANGE ........................................................................................................52  
DELETING AUTORANGE RANGES........................................................................................................53  
<2RES> (RESOLUTION).............................................................................................................................53  
<3STAB>......................................................................................................................................................54  
<4UL> (UPPER LIMIT) ................................................................................................................................55  
OVER PRESSURE FUNCTION...............................................................................................................57  
<5ATEST>....................................................................................................................................................57  
3.4.1.1  
3.4.1.2  
3.4.2  
3.4.3  
3.4.4  
3.4.4.1  
3.4.5  
[SPECIAL] .............................................................................................................................................57  
3.5.1  
3.5.1.1  
3.5.2  
3.5.2.1  
3.5.2.2  
3.5.2.3  
3.5.2.4  
3.5.3  
<1AUTOZ>...................................................................................................................................................58  
EDIT AUTOZ ............................................................................................................................................62  
<2REMOTE>................................................................................................................................................62  
<1COM1, 2COM2>...................................................................................................................................63  
<3IEEE-488>............................................................................................................................................63  
<4FORMAT> ............................................................................................................................................63  
<5RS232 SELF-TEST>............................................................................................................................64  
<3HEAD> .....................................................................................................................................................64  
<4SDS>........................................................................................................................................................65  
<1TEMP OPEN/CLOSE>.........................................................................................................................65  
<2FULL TIME ON/OFF> ..........................................................................................................................66  
<5PREFS> ...................................................................................................................................................66  
<1SCRSVR> ............................................................................................................................................67  
<2SOUND> ..............................................................................................................................................67  
<3TIME>...................................................................................................................................................67  
<4ID>........................................................................................................................................................68  
<5LEVEL> (SECURITY)...........................................................................................................................68  
<6PUNIT>.....................................................................................................................................................71  
<7INTERNAL> .............................................................................................................................................73  
<1BARO>.................................................................................................................................................73  
<2READRT> ............................................................................................................................................74  
<3RPT2X>................................................................................................................................................75  
<4LO VNT> ..............................................................................................................................................76  
<5LOG>....................................................................................................................................................77  
<8CAL>........................................................................................................................................................77  
<9RESET> ...................................................................................................................................................78  
<1SETS>..................................................................................................................................................78  
<2 UNITS> ...............................................................................................................................................79  
<3ATEST>................................................................................................................................................79  
<4 CAL> ...................................................................................................................................................79  
<5 ALL>....................................................................................................................................................80  
3.5.4  
3.5.4.1  
3.5.4.2  
3.5.5  
3.5.5.1  
3.5.5.2  
3.5.5.3  
3.5.5.4  
3.5.5.5  
3.5.6  
3.5.7  
3.5.7.1  
3.5.7.2  
3.5.7.3  
3.5.7.4  
3.5.7.5  
3.5.8  
3.5.9  
3.5.9.1  
3.5.9.2  
3.5.9.3  
3.5.9.4  
3.5.9.5  
© 2004-2007 DH Instruments, a Fluke Company  
Page II  
TABLE OF CONTENTS  
4. REMOTE OPERATION ....................................................... 81  
4.1  
4.2  
OVERVIEW............................................................................................................................................81  
INTERFACING.......................................................................................................................................81  
4.2.1  
RS232 INTERFACE.....................................................................................................................................81  
COM1.......................................................................................................................................................81  
IEEE-488..................................................................................................................................................82  
COM2.......................................................................................................................................................82  
4.2.1.1  
4.2.1.2  
4.2.1.3  
4.3  
4.4  
4.5  
4.6  
PROGRAMMING FORMATS.................................................................................................................82  
4.3.1  
4.3.2  
4.3.2.1  
4.3.2.2  
CLASSIC PROGRAM MESSAGE FORMAT...............................................................................................83  
ENHANCED PROGRAM MESSAGE FORMAT ..........................................................................................83  
USING COMMAND TYPE COMMANDS .................................................................................................83  
USING QUERY TYPE COMMANDS ...................................................................................................84  
COMMANDS..........................................................................................................................................85  
4.4.1  
4.4.2  
4.4.3  
4.4.4  
PROGRAMMING MESSAGES ....................................................................................................................85  
ERROR MESSAGESS.................................................................................................................................86  
PROGRAM MESSAGE DESCRIPTION OVERVIEW..................................................................................87  
PROGRAM MESSAGE DESCRIPTIONS....................................................................................................88  
STATUS REPORTING SYSTEM .........................................................................................................108  
4.5.1  
4.5.2  
4.5.3  
4.5.4  
ERROR QUEUE.........................................................................................................................................108  
STATUS BYTE REGISTER .......................................................................................................................108  
STANDARD EVENT REGISTER ...............................................................................................................110  
READY STATUS REGISTER ....................................................................................................................110  
IEEE STD. 488.2 COMMON AND STATUS PROGRAM MESSAGES................................................111  
4.6.1  
PROGRAM MESSAGE DESCRIPTIONS..................................................................................................112  
5. MAINTENANCE, ADJUSTMENTS AND CALIBRATION ................ 115  
5.1  
5.2  
OVERVIEW..........................................................................................................................................115  
CALIBRATION OF QUARTZ REFERENCE PRESSURE TRANSDUCERS (Q-RPTS) ......................115  
5.2.1  
PRINCIPLE ................................................................................................................................................115  
PA AND PM COEFFICIENTS ................................................................................................................116  
AS RECEIVED AND AS LEFT DATA ....................................................................................................116  
EQUIPMENT REQUIRED ..........................................................................................................................117  
GAS OPERATED Q-RPTS, A10M AND LOWER ..................................................................................117  
OIL OR GAS OPERATED Q-RPTS A14M AND HIGHER .....................................................................117  
SET-UP AND PREPARATION...................................................................................................................118  
RECOMMENDED CALIBRATION POINT SEQUENCE............................................................................119  
STANDARD CLASS Q-RPTS ................................................................................................................119  
PREMIUM CLASS Q-RPTS ...................................................................................................................120  
TURNING OFF ABSOLUTE AND NEGATIVE GAUGE MEASUREMENT MODES FOR AXXX  
(ABSOLUTE) Q-RPTS .........................................................................................................................122  
Q-RPT CALIBRATION USING CALTOOL FOR RPTS SOFTWARE........................................................122  
EDITING AND VIEWING Q-RPT CALIBRATION INFORMATION............................................................122  
Q-RPT CALIBRATION/ADJUSTMENT WITHOUT CALTOOL FOR RPTS SOFTWARE.........................124  
5.2.1.1  
5.2.1.2  
5.2.2  
5.2.2.1  
5.2.2.2  
5.2.3  
5.2.4  
5.2.4.1  
5.2.4.2  
5.2.5  
5.2.6  
5.2.7  
5.2.8  
5.3  
5.4  
5.5  
ADJUSTMENT OF ON-BOARD BAROMETER...................................................................................125  
RELOADING EMBEDDED SOFTWARE INTO FLASH MEMORY......................................................126  
SUBASSEMBLY DESCRIPTION AND LOCATION ............................................................................127  
5.5.1  
5.5.2  
5.5.3  
5.5.4  
5.5.5  
5.5.5.1  
5.5.5.2  
5.5.6  
MINI MICRO BOARD.................................................................................................................................127  
POWER SUPPLY MODULE......................................................................................................................127  
DRIVER BOARD........................................................................................................................................128  
ON-BOARD BAROMETER........................................................................................................................128  
Q-RPT MODULE........................................................................................................................................128  
HI Q-RPT MODULE ...............................................................................................................................128  
LO Q-RPT MODULE ..............................................................................................................................128  
DISPLAY....................................................................................................................................................128  
5.6  
Q-RPT MODULE PNEUMATIC SCHEMATICS...................................................................................129  
Page III  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
6. TROUBLESHOOTING .......................................................131  
7. APPENDIX ......................................................................135  
7.1  
7.2  
REMOTE [ENT] ...................................................................................................................................135  
UNIT CONVERSION............................................................................................................................136  
7.2.1  
PRESSURE................................................................................................................................................136  
8. WARRANTY ....................................................................137  
8.1  
OVERVIEW..........................................................................................................................................137  
9. GLOSSARY .....................................................................139  
© 2004-2007 DH Instruments, a Fluke Company  
Page IV  
TABLES & FIGURES  
TABLES  
Table 1. Reference Pressure Transducer (Q-RPT) Module Designations and Ranges ............................. 3  
Table 2. RPM4 Packing List......................................................................................................................... 7  
Table 3. Position Designators of Q-RPTs in an RPM4 System................................................................. 20  
Table 4. Settings and What They Are Specific To (Range, Measurement Mode, Q-RPT, System) ......... 21  
Table 5. Summary of RPM4 Function Key Operation................................................................................ 25  
Table 6. Settings Made by AutoRange ...................................................................................................... 31  
Table 7. AutoZ ON and OFF...................................................................................................................... 60  
Table 8. Security Levels............................................................................................................................. 70  
Table 9. UNIT Function - Available Units of Measure................................................................................ 72  
Table 10. READRT - Display Update Rates.............................................................................................. 74  
Table 11. Reset – Sets............................................................................................................................... 79  
Table 12. Reset – Cal ................................................................................................................................ 80  
Table 13. Reset – All.................................................................................................................................. 80  
Table 14. COM1 Pin Designations and Connections ................................................................................ 81  
Table 15. COM2 DB-9F Pin Designations................................................................................................. 82  
Table 16. Program Message List............................................................................................................... 85  
Table 17. Error #s and Descriptions .......................................................................................................... 86  
Table 18. 8 Bit Status Byte Register........................................................................................................ 108  
Table 19. 8 Bit Standard Event Register.................................................................................................. 110  
Table 20. 8 Bit Ready Status Register..................................................................................................... 110  
Table 21. Program Message List............................................................................................................. 111  
Table 22. Calibration Point Sequence, Standard Class, Axxx and Gxxx Q-RPTs .................................. 119  
Table 23. Calibration Point Sequence, Standard Class, BGxxx Q-RPTs................................................ 120  
Table 24. Calibration Point Sequence, Standard Class, BA100K Q-RPT............................................... 120  
Table 25. Calibration Point Sequence, Premium Class, Axxx and Gxxx Q-RPTs .................................. 121  
Table 26. Calibration Point Sequence, Premium Class, BGxxx Q-RPTs................................................ 121  
Table 27. Troubleshooting Guide............................................................................................................. 131  
Table 28. Pressure Unit of Measure Conversion Coefficients.................................................................136  
Table 29. DHI Authorized Service Providers ...........................................................................................137  
Page V  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
FIGURES  
Figure 1. Front Panel ................................................................................................................................... 8  
Figure 2. Rear Panel.................................................................................................................................... 9  
Figure 3. MAIN RUN Screen Display Fields.............................................................................................. 16  
Figure 4. Keypad Layout............................................................................................................................ 17  
Figure 5. Battery Pack/Charger ................................................................................................................. 23  
Figure 6. Status Register Schematic ....................................................................................................... 109  
Figure 7. Internal View ............................................................................................................................. 127  
Figure 8. Pneumatic/hydraulic schematics of RPM4 with Single Q-RPT Module ................................... 129  
Figure 9. Pneumatic/hydraulic schematics of RPM4 with Two Q-RPT Modules..................................... 130  
Figure 10. Remote [ENT] Connector Schematic ..................................................................................... 135  
© 2004-2007 DH Instruments, a Fluke Company  
Page VI  
ABOUT THIS MANUAL  
ABOUT THIS MANUAL  
This manual is intended to provide the user with the basic information necessary to operate an RPM4  
reference pressure monitor. It also includes a great deal of additional information provided to allow you to  
optimize RPM4 use and take full advantage of its many features and functions.  
RPM4-AD is a special air data configuration of RPM4 which has its own dedicated manual, p/n  
550148. This manual is for all other configurations of RPM4. If your are using an RPM4-AD (“-AD” in  
front panel configuration window) use the RPM4-AD Operation and Maintenance Manual p/n 550148.  
Before using the manual, take a moment to familiarize yourself with the Table of Contents structure:  
Sections 1, 2 and 3 should be read by all first time RPM4 users. Section 3 is most important for those  
using the local front panel interface but should be read over by all users to familiarize themselves with  
general RPM4 operating principles. Section 4 is for remote operation from an external computer. Section 5  
provides maintenance and calibration information. Section 6 is a quick troubleshooting guide. Use it to  
troubleshoot unexpected RPM4 behavior based on the symptom of that behavior. Certain words and  
expressions have specific meaning as they pertain to RPM4. The Glossary, Section 6, is useful as a  
quick reference for exact definition of specific words and expressions as they are used in the manual.  
For those of you who “don’t read manuals”, go directly to Section 2.3 to set up your RPM4 and then  
go to Section 2.4 for power-up and verification. This will get you up and running quickly with a minimal  
risk of causing damage to yourself or your new RPM4. THEN… when you have questions or start to  
wonder about all the great features you might be missing, get into the manual!  
Manual Conventions  
(CAUTION) is used in throughout the manual to identify user warnings and cautions.  
(NOTE) is used throughout the manual to identify operating and applications advice and  
additional explanations.  
[ ] indicates direct function keys (e.g., [RANGE]).  
< > indicates RPM4 screen displays (e.g., <1yes>).  
Page VII  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
NOTES  
© 2004-2007 DH Instruments, a Fluke Company  
Page VIII  
1. INTRODUCTION  
1. INTRODUCTION  
1.1  
PRODUCT OVERVIEW  
RPM4 is a stand-alone, microprocessor driven, reference pressure monitor intended to precisely  
measure gas or liquid pressure in a wide variety of pressure calibration, measurement and testing  
applications. It has been designed to provide very high performance and extensive features combined  
with maximum versatility and ease of use.  
RPM4 uses one or two quartz reference pressure transducer (Q-RPT) modules and, in some cases a  
barometer, to measure pressure.  
RPM4 can be controlled locally by the operator using its front panel display and keypad or remotely by a  
computer using ASCII character command strings transmitted over its standard RS232 or IEEE-488.2  
interface.  
RPM4 models are available in ranges from as low as - 3 to 3 kPa (0.4 psi) to as high as 280 MPa (40 000 psi)  
in absolute, gauge, compound gauge and differential measurement modes.  
RPM4 can be integrated into a PPC3 Pressure Controller/Calibrator System to serve the PPC3’s external  
pressure measuring reference (see the PPC3 Operation and Maintenance Manual).  
A special configuration of RPM4 designated RPM4-AD is available for air date (altitude and  
airspeed) applications. The RPM4-AD model has its own specific manual p/n 550148.  
Page 1  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
1.2  
SPECIFICATIONS  
1.2.1  
GENERAL SPECIFICATIONS  
85 to 264 VAC, 50/60 Hz, 25 VA max consumption  
and 12VDC, 1.2 A  
Power Requirements  
15 to 35 °C  
Operating Temperature Range  
Storage Temperature Range  
Vibration  
- 20 to 70 °C  
Meets MIL-T-28800D  
To prevent product overheating, provide proper ventilation. Allow 10 cm  
(4 in.) clearance from rear panel cooling fan.  
Ventilation  
5 kg (11 lb) approx. (varies slightly with number and type of Q-RPT modules)  
10 cm H x 22.7 cm W x 24 cm D (3.9 in. x 9.3 in. x 9.5 in.)  
Motorola 68302, 16 MHz  
Weight  
Dimensions  
Microprocessors  
Communication Ports  
Fuses  
RS232 (COM1, COM2), IEEE-488.2  
1 A, 250 VAC fuse, 5 x 20 mm, time lag type fuse  
Internal power supply fuse not replaceable by operator: 2.5A, 250 VAC  
One or two independent quartz reference pressure transducer (Q-RPT)  
modules cover vacuum to 280 MPa (40 000 psi)  
Pressure Ranges  
Operating Medium  
Any clean, dry, non-corrosive gas or liquid. Q-RPTs less than 7 MPa full scale,  
gas only  
Pressure Connections  
Q-RPTs up to A70M  
1/8 in. NPT F  
Q-RPTs > A70M  
DH500 F  
TEST(+):  
TEST(-):  
1/8 in. NPT F  
None  
VENT or ATM:  
10-32 UNF (VENT)  
10-32 UNF (ATM)  
DH500 is a gland and collar type fitting for 6mm (1/4 in.) coned and left  
hand threaded tubes equivalent to AE F250C, HIP HF4, etc.  
Included on all gas operated Q-RPT modules of A7M or lower. Isolates  
Q-RPT module TEST(+) port and vents it to atmosphere. SDS is not included  
with liquid filled Q-RPTs.  
Maximum Working Pressure: 104 % Q-RPT maximum  
Maximum Pressure Without Damage: 125 % Q-RPT maximum  
Self Defense System (SDS™)  
Pressure Limits  
Maximum SDS Protection Pressure: 10 MPa (1 500 psi):  
Without Damage: 13 MPa (2 000 psi)  
Available, must be specified  
CE Mark  
1.2.2  
PRESSURE MEASUREMENT SPECIFICATIONS  
1.2.2.1  
QUARTZ REFERENCE PRESSURE TRANSDUCER (Q-RPT)  
RPM4 can be configured with one or two quartz reference pressure transducer (Q-RPT)  
modules to measure pressure. The type (Axxx, Gxxx, BGxxx, BAxxx) and range of  
the Q-RPT module(s) determines the RPM4 measurement specifications.  
All Q-RPTs whose maximum pressure is over 200 kPa (30 psi) are of the absolute  
pressure type (Axxx) using an evacuated, permanently sealed reference.  
Axxx Q-RPTs can measure absolute, gauge and negative gauge pressure. Gauge  
pressure with an Axxx Q-RPT is defined by offsetting atmospheric pressure and  
applying dynamic compensation for atmospheric changes using the on-board  
barometer (see Section 3.2.2). Gxxx (gauge) Q-RPTs can measure positive gauge  
pressure only. BGxxx (bi-directional gauge) Q-RPTs can measure gauge and  
negative gauge pressure. See Section 3.3.3 for additional information on  
absolute, gauge and negative gauge measurement modes.  
RPM4s configured with two Q-RPT modules have independent TEST ports and can  
measure separately. Two Q-RPTs can also be used together to operate in  
differential mode (see Section 3.3.3.1) and parallel mode (see Section 3.2.4).  
© 2004-2007 DH Instruments, a Fluke Company  
Page 2  
1. INTRODUCTION  
Q-RPTs of A10M and lower are available with two different performance  
levels, STANDARD class and PREMIUM class. See the product label on the  
RPM4 rear panel, the Q-RPT module label on the rear panel and/or the  
product calibration reports to determine the class of the Q-RPT(s) installed  
in RPM4.  
Table 1. Reference Pressure Transducer (Q-RPT) Module Designations and Ranges  
SI VERSION  
US VERSION  
MAXIMUM  
RANGE  
[kPa]  
MAXIMUM  
RANGE  
[psi]  
MAXIMUM  
RANGE  
[psi]  
MAXIMUM  
RANGE  
[kPa]  
Q-RPT  
DESIGNATION  
Absolute  
280 000  
200 000  
140 000  
100 000  
70 000  
40 000  
20 000  
14 000  
10 000  
7 000  
3 500  
2 000  
1 400  
700  
Gauge  
280 000  
200 000  
140 000  
100 000  
70 000  
40 000  
20 000  
14 000  
10 000  
7 000  
3 500  
2 000  
1 400  
700  
Absolute  
40 000  
30 000  
20 000  
15 000  
10 000  
6 000  
3 000  
2 000  
1 500  
1 000  
500  
Gauge  
40 000  
30 000  
20 000  
15 000  
10 000  
6 000  
3 000  
2 000  
1 500  
1 000  
500  
A280M-L1  
A200M-L1  
A140M-L1  
A100M-L1  
A70M1  
A40M1  
A20M1  
A14M1  
A10M1  
A7M1  
A3.5M1  
A2M1  
300  
300  
A1.4M1  
A700K1  
A350K1  
A200K1  
A160K1  
A100K1  
BA100K4  
G200K2  
G100K2  
G15K2  
200  
200  
100  
100  
350  
250  
50  
35  
200  
100  
30  
15  
160  
60  
23  
8
110  
10  
16  
1.5  
110  
--  
16  
--  
--  
200  
--  
30  
--  
100  
--  
15  
--  
--  
15  
--  
--  
2.2  
BG15K3  
±15  
± 2.2  
1. All AXXXX RPTs support absolute, gauge and compound (negative) gauge modes.  
2. All GXXXX RPTs are positive gauge mode only.  
3. BG15K is bi-directional gauge from - 15 to + 15 kPa (- 2.2 to + 2.2 psi).  
4. BA100K is a barometric range whose low point is 70 kPa absolute (10 psi).  
Page 3  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
30 minute temperature stabilization recommended from  
cold power up.  
Warm Up Time  
To 1 ppm, user adjustable  
5 to 35 °C  
Resolution  
Compensated Temperature Range  
Acceleration Affect  
± 0.008 % /g maximum, worst axis  
Allows operation at ± 20° from reference plane without  
significant effect  
± 0.005% of reading  
Predicted One Year Stability  
(all classes and types)1  
Q-RPTs UP TO A10M (1500 psi)  
STANDARD CLASS  
PREMIUM CLASS  
± 0.005% of reading, 0.0015%  
of AutoRanged span, or  
0.0005% of Q-RPT span,  
whichever is greater 5  
Precision2  
± 0.008% of reading or  
0.0024% of Q-RPT span,  
whichever is greater 4  
Measurement Uncertainty3  
± 0.01% of reading or 0.0030%  
of Q-RPT span, whichever is  
greater 4  
± 0.008 % of reading, 0.0024%  
of AutoRanged span, or  
0.0007% of Q-RPT span,  
whichever is greater 5  
Q-RPTs A14M TO A140M (2 000 to 20 000 psi)  
Precision2  
± 0.012% of reading or 0.0036% of Q-RPT span, whichever is  
greater 4  
Measurement Uncertainty3  
± 0.013% of reading or 0.0039% of Q-RPT span, whichever is  
greater 4  
Q-RPTs A200M TO A280M (30 000 to 40 000 psi)  
Precision2  
± 0.015% of reading or 0.0045% of Q-RPT span, whichever is  
greater 4  
Measurement Uncertainty3  
± 0.018% of reading or 0.0054% of Q-RPT span, whichever is  
greater 4  
1. Predicted Q-RPT measurement stability limit (k=2) over one year assuming regular use of AutoZero function. AutoZero  
occurs automatically in gauge mode whenever vented, by comparison with barometric reference in absolute mode.  
Absolute mode predicted one year stability without AutoZ is ± (0.005 % Q-RPT span + 0.005 % of reading).  
2. Combined linearity, hysteresis, repeatability. Add + 1 Pa (0.00015 psi) in gauge mode with an Axxx (absolute) Q-RPT for  
the resolution and short term stability of the on-board barometer.  
3. Maximum deviation of the Q-RPT indication from the true value of applied pressure including precision, predicted one year  
stability limit, temperature effect and calibration uncertainty, combined and expanded (k=2) following the ISO “Guide to the  
Expression of Uncertainty in Measurement.”  
4. % of reading value times measured pressure from 100 to 30 % of Q-RPT span. Under 30 % of Q-RPT span, % of reading  
value times 30 % of Q-RPT span. For example, if the Q-RPT is a Standard A160K, the Measurement Uncertainty in  
pressure is 0.010% times the measured pressure to 48 kPa (160 kPa span x 30%) and 0.0048 kPa (160 kPa span x 30%  
x 0.01%) under 48 kPa.  
5. % of reading value times measured pressure from 100 to 30 % of AutoRanged span. Under 30% of AutoRanged span, % of  
reading value times 30% of AutoRanged span. If AutoRanged span is less then 30% of maximum Q-RPT span, % of reading  
values times measured pressure, or % of reading times 9% of Q-RPT span, whichever is greater. For example, if the Q-RPT is a  
Premium A160K and AutoRanged span is 160 kPa, the Measurement Uncertainty in pressure is measured pressure x 0.008% to  
48 kPa (160 kPa AutoRanged span x 30%) and 0.0038 kPa (160 kPa span x 30% x 0.008%) under 48 kPa. If the AutoRanged  
span is 100 kPa (greater than 30% of 160 kPa maximum Q-RPT span), the Measurement Uncertainty in pressure is measured  
pressure x 0.008% to 30 kPa (100 kPa AutoRanged span x 30%) and 0.0025 kPa (100 kPa span x 30% x 0.008%) under 30 kPa.  
If the AutoRanged span is 30 kPa (less than 30% of the 160 kPa maximum Q-RPT span), the Measurement Uncertainty in  
pressure is measured pressure x 0.008% to 14.4 kPa (160 kPa maximum Q-RPT span x 9%) and 0.0012 kPa (160 kPa maximum  
Q-RPT span x 9% x 0.008%) under 14.4 kPa.  
1.2.2.2  
ON-BOARD BAROMETER  
The on-board barometer is used only to measure changes in atmospheric pressure  
to provide dynamic compensation of the Q-RPT’s atmospheric pressure offset when  
using an Axxx (absolute) Q-RPT to make gauge pressure measurements and for  
line pressure compensation of G15K and BG15K Q-RPTs.  
There is no on-board barometer in RPM4s that have Gxxx (gauge)  
Q-RPTs only.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 4  
1. INTRODUCTION  
1.2.3  
BATTERY AND CHARGER PACK  
100 to 240 VAC, 50/60 Hz, 15 W max consumption  
Power Requirements  
0 to 50 °C  
Operating Temperature Range  
Storage Temperature Range  
Vibration  
- 20 to 50 °C  
Meets MIL-T-28800D  
2 kg (4.4 lb)  
Weight  
8 cm H x 22.5 cm W x 20 cm D (3.1 in. x 8.9 in. x 7.9 in.)  
Dimensions  
Nickel Metal-Hydride  
12 VDC  
Battery Type  
Battery Voltage  
Battery Capacity  
Typical: 9000 mAh  
Min: 8200 mAh  
Full charge from empty, 14 to 16 hours approx.  
8 to 12 hours  
Charge Time  
Approx. Run Time, Full Charge  
Page 5  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
NOTES  
© 2004-2007 DH Instruments, a Fluke Company  
Page VI  
2. INSTALLATION  
2. INSTALLATION  
2.1  
UNPACKING AND INSPECTION  
2.1.1  
REMOVING FROM PACKAGING  
RPM4 is delivered in a corrugated container with polyethylene inserts to hold it in place; or in  
the optional molded, medium density polyethylene shipping case with a custom foam insert  
for holding the RPM4.  
Remove the RPM4 and its accessories from the shipping container and remove each  
element from its protective plastic bag.  
2.1.2  
INSPECTING CONTENTS  
Check that all items are present and have no visible damage.  
A standard RPM4 includes all items indicated in Table 2.  
Table 2. RPM4 Packing List  
DESCRIPTION  
PART #  
FAM008  
1 ea.  
1 ea.  
RPM4 Reference Pressure Monitor  
Calibration Report  
550100  
ACCESSORIES:  
401967 (401967-CE)  
550129  
1 ea.  
1 ea.  
1 ea.  
1 ea.  
Operation and Maintenance Manual  
Power Cord (7.5 ft.)  
100770 (100770-CE)  
103303  
Ferrite sleeve (snap on to COM2 cable for CE)  
General Accessories Disk (white CD)  
102987  
OPTIONAL BATTERY/CHARGER PACK  
401904 (401904-CE)  
401980  
1 ea.  
1 ea.  
1 ea.  
1 ea.  
Battery/charger pack  
Battery/charger pack to RPM4 cable  
Power Cord (7.5 ft.)  
401979  
100770 (100770-CE)  
560062  
Instruction Sheet  
Page 7  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
2.2  
SITE REQUIREMENTS  
Install RPM4 on a flat, stable surface at a convenient height. The front feet can be extended so that the  
unit can be inclined for easier viewing. The RPM4 can also be mounted in a standard 19 in. rack mount  
using the optional rack mount kit.  
2.3  
SETUP  
2.3.1  
PREPARING FOR OPERATION  
To prepare RPM4 for check out and operation:  
Remove the plastic caps from the RPM4 rear panel pressure connections.  
Remove the protective plastic sheet from the front panel display.  
Familiarize yourself briefly with the front and rear panels (see Section 2.3.2).  
2.3.2  
FRONT AND REAR PANELS  
2.3.2.1  
FRONT PANEL  
1. Ready/Not Ready Indicator 4. Cursor Control Keys  
2. Display  
5. Multi-Function Keypad  
3. Remote Activity Indicator  
Figure 1. Front Panel  
© 2004-2007 DH Instruments, a Fluke Company  
Page 8  
2. INSTALLATION  
2.3.2.2  
REAR PANEL  
1. 12VDC Power Supply  
Connection  
10. TEST(+) Pressure Port, Lo Q-RPT  
(if Lo Q-RPT present)  
11. TEST(-) Pressure Port, Lo Q-RPT  
(if Lo-QRPT present, <A100M only)  
12. TEST(+) Pressure Port, Hi Q-RPT  
13. TEST(-) Pressure Port, Hi Q-RPT  
(<A100M only)  
2. Remote [ENT] Connector  
3. IEEE-488 Connector  
4. COM2 Connector  
5. COM1 Connector  
6. Power Switch  
14. VENT (<A10M>) or ATM (>A10M)  
Pressure Port, Lo Q-RPT  
15. VENT or ATM Pressure Port, Hi Q-RPT  
16. Product Label (bottom of case)  
7. Fuse  
8. Electrical Power Connector  
(IEC-320-C13)  
9. Fan  
Figure 2. Rear Panel  
2.3.3  
POWER CONNECTION  
2.3.3.1  
85 TO 264 VAC, 50/60 HZ VAC POWER  
Check that the RPM4 power switch is OFF.  
Connect the supplied power cable to the rear panel power module.  
Connect the other end of the power cable to an electrical supply of 85 to 264 VAC,  
50/60 Hz.  
2.3.3.2  
BATTERY PACK  
Charge the battery pack fully (see Section 3.2.6).  
Connect the RPM4 12VDC power connection on the rear panel of the RPM4  
to the 12 VDC power connection on the battery/charge pack using the cable  
supplied with the pack.  
See Section 3.2.6 for additional information on battery/charger pack  
operation and maintenance.  
Page 9  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
2.3.4  
REMOTE [ENT] CONNECTION (FOOTSWITCH OR OTHER  
SWITCH)  
Connect the optional remote ENTER footswitch, if available or a user supplied switch fitted to  
the optional cable (see Section 7.1). Connect the cable to the RPM4 rear panel connection  
labeled REMOTE ENTER. Activating the switch is equivalent to pressing the [ENT] key on  
the front panel (see Section 3.1.3).  
2.3.5  
CONNECTING TO MEASURE PRESSURE (TEST(+) AND  
TEST(-) PORTS)  
Using a pressure connecting hose or tube of appropriate pressure rating, connect the device  
or system to be tested to the RPM4 TEST(+) port.  
The RPM4 TEST(+) connection is 1/8 in. NPT female (Q-RPTs of A70M or lower) or DH500 F  
(Q-RPTs higher than A70M).  
DH500 is a gland and collar type fittings for 6.35 mm (1/4 in.) coned and left hand  
threaded tubes. DH500 is equivalent to AE F250C, HIP HF4, etc.  
The TEST(+) and TEST(-) ports on Q-RPT modules of A70M and lower are threaded into  
the aluminum Q-RPT manifold. Take care in making and breaking fittings not to cross  
thread or otherwise damage the threads. It is recommended that an adaptor be  
installed in the in Q-RPT manifold and make break operations be made on the adaptor  
rather than the manifold.  
SDS Self Defense System: Q-RPT modules designated A7M or lower include the SDS Self  
Defense System. SDS, operated properly, allows a the Q-RPT TEST(+) port to be left  
connected to a pressure up to 10 MPa (1 500 psi) without damage to the Q-RPT.  
Do NOT attempt to use SDS in this manner without first becoming thoroughly familiar  
with its operation and limitations (see Sections 3.2.7, 3.3.8, 3.5.4).  
Q-RPT MODULE TEST(+) AND TEST(-) PORTS  
Q-RPT modules of A70M and lower have both TEST(+) and TEST(-) ports. Q-RPT modules  
greater than A70M have a TEST(+) port only. See Section 5.6, Figure 8 for RPM4 Q-RPT  
module TEST port configurations.  
The TEST(+) port is connected to Axxx (absolute) Q-RPTs’ sole measurement port and to the  
high side of Gxxx or BGxxx (gauge or bi-directional gauge) Q-RPTs.  
The TEST(-) port of Axxx and BGxxx Q-RPTs is connected to RPM4’s internal barometer.  
The TEST(-) is connected to the low side of Gxxx (gauge) or Gxxx (bi-directional gauge)  
Q-RPTs.  
When operating in absolute mode: The TEST(-) port, if present, is left open to  
atmosphere.  
When operating in gauge or negative gauge mode with a range greater than 50 kPa  
(7.5 psi): The TEST(-) port, if present, is normally left open to atmosphere. A possible  
exception is when the device or system under test is in an ambient pressure that may differ  
significantly from the ambient pressure around the RPM4. For example, if the RPM4 is  
measuring the pressure applied to DUTs in an environmental chamber, the pressure in the  
environmental chamber may be different from ambient pressure around the RPM4. In this  
© 2004-2007 DH Instruments, a Fluke Company  
Page 10  
2. INSTALLATION  
case, connecting a tube from the TEST(-) port to the inside of the chamber may improve  
measurement results. If the Q-RPT in use is an Axxx Q-RPT, this tube must be left open to  
the environment so that the pressure inside cannot deviate too far from ambient. When using  
an Axxx Q-RPT, if this tube is connected to the low or reference side of DUTs, be sure to  
open it to the local environment as well.  
When operating in gauge or negative gauge mode with a range less than 50 kPa  
(7.5 psi): As a general rule, it is preferable to connect the RPM4 TEST(-) port(s) directly to  
the low or reference side of the device under test to assure that these are at the same  
pressure. When using an Axxx Q-RPT, this connection must also be open to atmosphere.  
When using a Gxxx or BGxxx Q-RPT, it is preferable that this connection not be open to  
atmosphere.  
Do not connect a pressure supply to the TEST(-) port. The pressure applied to this port  
should be maintained at atmospheric pressure (between 70 and 110 kPa (10 and 16 psia)).  
Exceeding these limits may damage a Gxxx or BGxxx Q-RPT and/or the RPM4’s on-board  
barometer.  
Using the RPM4 with gas operated Q-RPTs connected to a system with liquid  
contaminants without taking proper precautions to purge the system and test line may  
cause contamination of the RPM4 that will require non-warranty service.  
2.3.6  
THE VENT OR ATM PORT  
RPM4 Q-RPT modules of A7M and lower have a VENT port. The VENT port is connected to the  
TEST(-) port when SDS is CLOSED (see Section 5.6, Figure 8). For Axxx and BGxxx Q-RPTs,  
the RPM4 on-board barometer, is connected to the VENT port when SDS is CLOSED.  
The VENT port should always be left completely unobstructed and open to atmosphere.  
RPM4 Q-RPT modules of A10M and higher have an ATM port. The ATM port is connected  
to the RPM4 on-board barometer. The ATM port should always be left completely unobstructed  
and open to atmosphere.  
NEVER plug, obstruct or connect a supply pressure to the RPM4 VENT or ATM port. This  
may adversely affect GAUGE mode operation and AutoZeroing functions.  
2.3.7  
CHECK/SET SECURITY LEVEL  
RPM4 has a security system based on user levels. By default, the security system is set to  
“low”, which includes access restriction to internal calibration coefficients, and there is no  
password required to change the security level. See Section 3.5.5.5 for information on the  
security level system. As part of the RPM4 startup, determine the security level that is  
appropriate for the RPM4 and set a password if desired.  
RPM4 is delivered with the security level set to “low” to avoid inadvertent altering of critical  
internal settings but with access to changing security levels unrestricted. It is recommended  
that the low security level be maintained at all times and password protection be  
implemented if control over setting of security levels is desired.  
Page 11  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
2.3.8  
TURN OFF ABSOLUTE AND NEGATIVE GAUGE MODE  
(AXXX RPT)  
If your RPM4 has one or two Axxx (absolute) Q-RPTs, it is able to operate in  
gauge, negative gauge and absolute measurement modes (see Section 3.3.3).  
If the RPM4 will be used in gauge mode only, the other measurement modes can  
be turned off so they are no longer accessible. Turning off modes that are not  
needed can avoid confusion and/or accidental use of the wrong measurement mode.  
See Section 5.2.5 for complete information on turning off absolute and negative  
gauge measurement modes.  
Turn off absolute and negative gauge mode if desired.  
2.3.9  
SDS FULL TIME OFF  
Gas operated Q-RPT modules of A7M or less, include the SDS Self Defense  
System (see Section 3.2.7) to shut off the Q-RPT from the TEST(+) port. If this  
function is not desired, SDS can be turned full time off so that in regular  
operation, SDS is not present. With SDS full time off, the SDS overpressure  
protection is still active.  
See Section 3.5.4.2 for instructions on turning SDS full time off if desired.  
2.3.10 PARALLEL MEASUREMENT MODE  
If your RPM4 has two Q-RPTs of the same type (Axxx, Gxxx, BGxxx), it supports  
parallel measurement mode in which both RPTs are used simultaneously to  
measure a common pressure, statistically reducing uncertainty in the  
measurement. Parallel measurement creates a new Q-RPT, designated <HL>,  
which is the combination of the Hi and Lo Q-RPTs. See Section 3.2.4 for  
complete information on parallel measurement mode.  
Turn on parallel measurement mode if desired.  
2.4  
POWER-UP AND VERIFICATION  
2.4.1  
SWITCH POWER ON  
Actuate the power switch on the RPM4 rear panel (if a 12 VDC power supply is already connected  
to the 12 VDC connection, RPM4 power is already on). Observe the front panel display as  
RPM4 initializes, error checks and goes to the MAIN RUN screen (see Section 3.1.1).  
RPM4 default power-up condition is Hi Q-RPT active, SDS closed if present.  
If the RPM4 fails to reach the MAIN RUN screen, service is required. Record the sequence  
of operations and displays observed.  
If the RPM4 Q-RPT module is equipped with SDS, SDS is CLOSED at power up and the  
TEST(+) port is shut off. This causes <SDS CLOSED> to be flash periodically in the main  
run screen in place of the measured pressure value.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 12  
2. INSTALLATION  
2.4.2  
CHECK PRESSURE MEASUREMENT OPERATION  
2.4.2.1  
CHECKING ABSOLUTE MODE PRESSURE MEASUREMENT  
If the RPM4 has an Axxx (absolute) Q-RPT, check that it operates properly in  
absolute mode.  
Make sure that the TEST(+) port is vented to atmosphere.  
Use the [RANGE] function key to select the Axxx (absolute) Q-RPT DF range  
(see Section 3.3.1).  
Press the [MODE] function key and select <absolute> mode (see Section 3.3.3).  
Use [UNIT] to change the pressure unit if desired (see Section 3.3.2).  
If SDS is CLOSED (<SDS CLOSED> flashes over the display of pressure on  
the top line of the display), OPEN SDS. Press [SDS], <2yes> to OPEN SDS  
(see Section 3.3.8).  
Do NOT OPEN SDS with a pressure higher than the maximum pressure of the  
Q-RPT applied to the TEST(+) port. Damage to the Q-RPT may result.  
Observe the current value of atmospheric pressure. Check that the value agrees  
with the local value of atmospheric pressure within measurement tolerances (see  
Section 1.2.2.1) Repeat this process for both Axxx (absolute) Q-RPTs if there  
are two in the RPM4. . If a Q-RPT does not agree within tolerance, it may need  
to be AutoZeroed (see Section 3.3.9), calibrated (see Section 5.2)  
or repaired.  
2.4.2.2  
CHECKING GAUGE MODE PRESSURE MEASUREMENT  
Make sure that the TEST(+) port is open to atmosphere.  
Press the [MODE] function key and select <gauge> mode. Use [UNIT] to change  
the pressure unit if desired (see Section 3.3.2)..  
If SDS is CLOSED (<SDS CLOSED> flashes over the display of pressure on the  
top line of the display), OPEN SDS. Press [SDS], <2yes> to OPEN SDS.  
Do NOT OPEN SDS with a pressure higher than the maximum pressure of the  
Q-RPT applied to the TEST(+) port. Damage to the Q-RPT may result.  
The value indicated should be near zero. It is normal for the Q-RPT to indicate  
a value other than zero when vented when gauge mode is first entered or the  
range is changed. Press [AutoZ]. This runs AutoZ to zero the Q-RPT reading  
(see Section 3.3.9.1). Upon return to the main run screen, observe that the  
indication of measured pressure has zeroed.  
If the display fails to zero properly, RPM4 may need repair.  
Page 13  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
2.5  
SHORT TERM STORAGE  
The following is recommended for short term storage of RPM4:  
Vent the RPM4 test port  
Switch power OFF.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 14  
3. OPERATION  
3. OPERATION  
3.1  
USER INTERFACE  
RPM4 is designed to offer a balance between simple, straight forward operation and the availability of a  
wide variety of advanced functions with a high level of operator discretion. The local operator interface is  
through a 2 x 20 character alphanumeric display, a function/data keypad, a cursor control pad and a  
Ready/Not Ready indicator.  
Remote communications are by RS232 (COM1) and IEEE-488. See Section 4 for information on remote  
communication.  
3.1.1  
MAIN RUN SCREEN  
The RPM4 MAIN RUN screen is its home display that is reached on power-up and from  
which other functions and menus are accessed. It is the very top level of all menu structures.  
The MAIN RUN screen is where RPM4 is left in normal operation. It displays the current  
measured pressure as well as a variety of additional information if desired.  
Figure 3 and its legend summarize the RPM4 MAIN RUN screen fields and their functions.  
RPM4 has a screen saver function which causes the display to dim if no key is pressed for  
10 minutes. Pressing a key restores full power to the display. The screen saver time can  
be changed or screen saving can be completely suppressed (see Section 3.5.5.1).  
Page 15  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
PRESSURE1UNITM hzRR  
DDISPLAYFUNCIONnn/nn  
DISPLAY FIELD  
NAME  
PURPOSE  
CONTENTS  
SECTION  
1. PRESSURE1 Measured  
pressure  
Displays pressure  
measured by the  
active Q-RPT  
Numerical pressure value and sign. 1.2.2.1  
Intermittently flashes <SDS  
3.2.7  
CLOSED> when the Q-RPT is shut  
off from the TEST(+) port by SDS.  
2. UNIT  
Unit of  
measure  
Identifies unit of  
measure in which  
pressure values are  
displayed  
Pressure unit abbreviation  
3.3.2  
3. M  
4. h  
Measurement Identifies  
3.3.3  
3.3.7  
<a>  
<g>  
<d>  
absolute  
gauge or negative gauge  
differential  
mode  
measurement mode  
of displayed pressure  
Head  
pressure  
indicator  
Indicates whether a  
fluid head correction  
is applied to  
<h>  
the fluid head is not zero  
<blank> fluid head is zero  
PRESSURE1  
5. z  
AutoZero  
indicator  
Indicates whether  
the AutoZero function  
is ON or OFF for the  
active Q-RPT and  
measurement mode  
3.5.1  
3.2.3  
<z>  
AutoZ is ON  
<blank> AutoZ is OFF  
6. RR  
Active  
Indicates the position  
of the active Q-RPT  
in the RPM4  
<Hi> Hi Q-RPT  
<Lo> Lo Q-RPT  
Q-RPT  
position  
indicator  
<HL> Hi and Lo Q-RPTs together in  
parallel measurement mode  
<Hd> Hi and Lo Q-RPTs together in  
differential measurement  
mode  
7. nn/nn  
Sequence  
progress  
indicator  
Indicates progress of  
ATest sequence,  
during test execution  
3.3.10  
3.3.6  
<NN/NN> Number of this point  
over total number of points  
in the sequence  
8. DISPLAY  
FUNCTION  
Information  
specific to  
Pressure indication  
depending on current  
Numerical pressure value  
and sign.  
the DISPLAY RPM4 DISPLAY  
<PPC3 EXT DEV:> when the RPM4  
is initialized as an external device  
to a PPC3 pressure controller.  
mode  
function. Leading  
character identifies  
the value  
9. D  
Pressure  
information  
indicator  
Pressure information  
indicator depending  
on current RPM4  
3.3.6  
<σ> Display mode is AVERAGE  
and value is standard deviation  
<R> Display mode is RATE and  
value is pressure rate of  
DISPLAY function.  
change per second  
<H> Display mode is HI/LO and  
value is high, then low  
<D> Display mode is DEVIATION  
and value is difference from  
current target  
<Σ, , > Display mode is RPT  
and value is measurement  
of inactive RPT  
<F> Display mode is FREEZE and  
value is last captured reading  
Blank, no character Current  
display mode is CLEAN  
Figure 3. MAIN RUN Screen Display Fields  
© 2004-2007 DH Instruments, a Fluke Company  
Page 16  
3. OPERATION  
3.1.2  
FUNCTION / DATA KEYPAD LAYOUT AND PROTOCOL  
The RPM4 has a function/data keypad for local operator access to direct  
functions, function menus and for data entry.  
1. The Function/Data keys allow very commonly 3. The Menu/Data keys provide access to  
used functions to be accessed directly by a  
single keystroke when pressed from the  
MAIN RUN screen (see Section 3.1.1).  
The name of the function is on the bottom  
half of the key. These keys enter numerical  
values when editing.  
function menus when pressed from the  
MAIN RUN screen. The menu name is on  
the bottom half of the key. The SETUP  
menu is for more frequently used functions  
(see Section 3.4). The SPECIAL menu is for  
functions that are not generally used as a part  
of day to day operation (see Section 3.5).  
These keys enter numerical values when editing.  
2. The Editing and Execution keys are for  
starting and suspending command execution,  
cursor control in menus and editing entries.  
Figure 4. Keypad Layout  
Pressing the [ENT] key generally causes execution or forward movement in the  
menu tree.  
Pressing the [ESC] key moves back in the menu tree and/or causes execution to  
cease or suspend. Pressing [ESC] repeatedly eventually returns to the MAIN RUN  
screen and, from there, allows momentary viewing of the RPM4 introduction  
screen.  
Pressing the [+/-] key changes a numerical sign when editing. It also toggles  
through multiple screens when available and, from some run screens, is a  
shortcut to a momentary display of active RANGE.  
Pressing the [ ], [ ], [ ] and [ ] keys allows up, down, reverse and  
forward cursor movement when editing data entry or moving in menus.  
Some screens go beyond the two lines provided by the display. This is  
indicated by a flashing arrow in the second line of the display. Press the  
cursor control keys to move the cursor to access the lines that are not  
visible or directly enter the number of the hidden menu choice if you know it.  
Page 17  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
3.1.3  
REMOTE [ENT] (ENTER) FOOTSWITCH  
The optional remote ENTER function is a switch that duplicates the function of the front panel  
[ENT] key. The remote ENTER function is serviced by a connector on the RPM4 rear panel.  
An optional footswitch is available to activate remote entry hands free or a different switch  
may be used. See Section 7.1 for information on remote ENTER switch wiring.  
The remote ENTER feature can be particularly convenient when running AutoTests  
(see Section 3.3.10) in which using a footswitch to [ENT] allows hands free operation. It can  
also be used, with the FREEZE display function (see Section 3.3.6.6) to capture the  
activation point of a pressure switch.  
3.1.4  
SOUNDS  
RPM4 is equipped with a variable frequency tone device to provide audible feedback and  
alarms. The beeper is used for the following indications.  
Brief beep. Choice between three frequencies or NO  
sound is available (see Section 3.5.5.2).  
Valid key press  
Descending two tone “blurp”  
Invalid key press  
Three two second beeps (see Section 3.3.5).  
Intermittent one second beeps (see Section 3.4.4).  
Eight second high frequency beep (see Section 3.4.4.1).  
Leak check completed  
Upper or lower limit exceeded  
Pmax! (overpressure limit)  
exceeded  
Rapid beeps for 8 seconds (3.2.4).  
Parallel measurement mode  
possible disconnection of the  
Hi and Lo Q-RPTs  
Ascending triad/descending triad (see Section 3.3.10).  
AutoTest in/out of tolerance  
reading  
3.2  
GENERAL OPERATING PRINCIPLES  
3.2.1  
PRESSURE READY/NOT READY  
There is a Ready/Not Ready indication LED on the RPM4 front panel. This indication is  
intended to provide the user with a clear and objective indication of when a stable pressure  
has been achieved. Ready is indicated when the current stability (rate of change) of  
pressure is less than the stability limit. The user can set the stability limit (see Section 3.4.3).  
The ready indication is often used when comparing the RPM4 and a test device to indicate  
when a valid reading can be made.  
In RPM4s with two Q-RPTs, the Ready/Not Ready indication always applies to the active  
Q-RPT, whose pressure measurement is displayed on the top line of the RPM4 display.  
When the inactive Q-RPT measurement is displayed on the second line using the RPT  
display mode, the Ready/Not Ready indication for the inactive RPT is indicated by the  
leading character on the line. <Σ> indicates Ready. < > or < > indicate Not Ready,  
pressure increasing or pressure decreasing.  
The Ready/Not Ready LED indications are:  
<Green > Pressure Ready  
<Red> Pressure Not Ready  
The pressure stability is within the stability limit.  
The pressure stability is NOT within the stability limit.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 18  
3. OPERATION  
In differential measurement mode (see Section 3.3.3.1), the LED Ready/Not Ready  
indication applies to the differential pressures.  
In parallel measurement mode (see Section 3.2.4), the LED Ready/Not Ready indication  
applies to the average pressure read by the <HL> Q-RPT.  
When RPM4 is being used as an external measurement reference of a PPC3 pressure  
controller, the Ready/Not Ready indication is still based on the RPM4 stability and  
stability limit only. The RPM4’s Ready/Not Ready LED does not indicate whether the  
PPC3 pressure control is Ready.  
3.2.2  
GAUGE AND NEGATIVE GAUGE MODES WITH AN AXXX  
(ABSOLUTE) Q-RPT, DYNAMIC COMPENSATION FOR  
ATMOSPHERIC PRESSURE  
Q-RPTs with the designation Axxx are intrinsically absolute but they are also used for gauge and  
negative gauge measurement modes (see Section 3.3.3,  PRINCIPLE). Gauge measurement  
modes are achieved by subtracting the value of atmospheric pressure, Poffset,G, from the  
Q-RPT’s absolute reading using AutoZ (see Section 3.2.2). The AutoZ routine that measures  
Poffset,G, is run by pressing [AutoZ] whenever RPM4 is in the vented condition. This assures  
the continuous updating of the Poffset,G value corresponding to atmospheric pressure. Gauge  
pressure is the measured absolute pressure, Pu, minus the atmospheric offset.  
Pgauge = Pu - Poffset,G  
However, atmospheric pressure may change between opportunities to run AutoZ and update  
the value of Poffset,G, for example when running an extended test without venting. RPM4 uses  
dynamic compensation for atmospheric pressure to correct for changes in atmospheric  
pressure between opportunities to run AutoZ and update Poffset,G. When AutoZ runs, and  
Poffset,G is determined, the reading of RPM4’s on board barometer, Patm,0, is also recorded.  
Later, when no longer vented, the change in atmospheric pressure, ΔPatm, since Poffset,G was  
updated, is the difference between the current barometer reading, Patm, and the barometer  
reading at the time of AutoZ execution, Patm,0  
:
ΔPatm = Patm - Patm,0  
Dynamic compensation for atmospheric pressure uses ΔPatm to correct the value of Poffset,G  
,
thus always compensating real time for changes in atmospheric pressure:  
Pgauge = Pu - Poffset,G - ΔPatm  
Gauge pressure measurement on an Axxx (absolute) Q-RPT allows instantaneous switching  
between gauge and absolute measurements modes. The additional uncertainty in gauge  
pressure mode due to the dynamic compensation for atmospheric pressure technique is a  
function of the resolution and short term stability of the on-board barometer, not its absolute  
measurement uncertainty. This additional uncertainty is ± 1 Pa (0.00015 psi).  
3.2.3  
MULTIPE RANGES (Q-RPTS, AUTORANGE AND INFINITE  
RANGING)  
An RPM4 may have one or two Q-RPTs. Position indication of the currently active Q-RPT is  
continuously displayed in the upper right hand corner of the MAIN RUN screen and most other  
screens. See Table 3 for position designation protocol for the Q-RPTs in an RPM4.  
See Table 1 for a complete listing of RPM4/RPM4 Q-RPT choices and their default ranges.  
Page 19  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
Table 3. Position Designators of Q-RPTs in an RPM4 System  
Q-RPT POSITION  
DISPLAY SYMBOL*  
Q-RPT with highest maximum pressure,  
Hi  
installed in HIGH RPT position  
Q-RPT with lower maximum pressure in  
dual Q-RPT RPM4, installed in LOW  
RPT position.  
Lo  
Two Q-RPTs being used simultaneously  
in parallel measurement mode  
HL  
Hd  
Hi Q-RPT when used in differential  
measurement mode  
*
The display symbol is included in the upper, right hand corner of most RPM4  
menu displays as a convenient indicator of the active Q-RPT.  
An RPM4 may have multiple ranges. Each RPM4 Q-RPT has a default range which is its  
maximum span. Additional ranges, lower than the Q-RPT’s maximum span, may also be  
created using AutoRange (see Section 3.3.4). Ranges created using are AutoRange  
temporary but may be saved with all their settings for reactivation (see Section 3.4.1).  
AN RPM4 range is identified by a range screen showing the Q-RPT used by the range, its current unit  
of measure and its full scale pressure in gauge and absolute (if available) measurement modes.  
The range screen is:  
1. Q-RPT designator.  
2. Type of range. DF for the Q-RPT’s default range; AR for a range  
created by AutoRange.  
Active A700K DF Hi  
psi 100g/100a  
3. Q-RPT position designator.  
4. Current pressure unit of measure.  
5. Full scale pressure in current unit of measure in gauge (<g>) and/or absolute  
(<a>) measurement mode depending on type of Q-RPT and range.  
The ranges available on an RPM4 system are accessed using [RANGE] (see Section 3.3.1)  
and/or created using [AutoRange] (see Section 3.3.4).  
Most settings made in an RPM4 range, such as unit of measure, measurement mode, display  
resolution, and stability setting are specific to the range. Settings selected while one range is  
active apply to that range and not to other ranges. The range specific settings are stored with  
the range and recalled whenever the range is made active. This makes setting up ranges a  
convenient way to store and recall frequently used operating configurations. See Table 4 for a listing  
of RPM4 adjustments and settings and whether they are range, Q-RPT or system specific.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 20  
3. OPERATION  
Table 4. Settings and What They Are Specific To  
(Range, Measurement Mode, Q-RPT, System)  
SETTING  
[Unit]  
PURPOSE  
SPECIFIC TO  
SECTION  
3.3.2  
Set pressure unit of measure  
Range  
Range  
[Mode]  
Set pressure measurement mode (absolute,  
gauge, negative gauge)  
3.3.3  
[Display]  
[Head]  
Set bottom line display function  
System  
System  
3.3.6  
3.3.7  
Set fluid head correction height, fluid, unit of  
measure  
[SDS]  
Open and close SDS  
Q-RPT  
3.3.8  
[AutoZ]  
Run AutoZ  
Q-RPT and measurement mode  
Range  
3.3.9  
3.4.2  
3.4.3  
3.4.4  
3.5.1  
3.5.5  
Resolution  
Stability  
Upper Limit  
AutoZ  
Set pressure display resolution  
Set Ready/Not Ready stability test.  
Set upper and lower pressure limit alarm  
AutoZ, ON/OFF, set and view values  
Set system user preferences  
Range  
Range and measurement mode  
Q-RPT and measurement mode  
System  
Screen Saver,  
Sound, Time,  
ID, Level  
Lo vnt  
Cal  
Q-RPT  
3.5.7.4  
3.5.8  
Set status of TEST(-) vent valve, if present  
Various Q-RPT and barometer calibration  
functions, including turning off absolute and  
negative gauge modes  
Q-RPT or barometer  
3.2.4  
PARALLEL MEASUREMENT MODE  
RPM4s equipped with two Q-RPT modules of the same type (Axxx, Gxxx, BGxxx) can be set  
to operate in parallel measurement mode.  
Parallel measurement mode is intended to improve measurement reliability and reduce measurement  
uncertainty by using the measurements of two Q-RPTs together. In parallel measurement  
mode, the measured pressure is the average of the readings of the two Q-RPTs.  
Parallel measurement mode is considered a third Q-RPT designated <HL> (combination of  
Hi and Lo). Once it has been set up, the HL Q-RPT can be selected using the [RANGE] key  
and operated with all the features of a Hi or Lo Q-RPT. When setting up parallel measurement,  
the Hi and Lo Q-RPTs can be suppressed so that only the HL Q-RPT is active. This feature is  
used when the RPM4 will always be used in HL mode.  
Parallel measurement mode is set up using [SPECIAL], <7internal>, <3RPT2x>  
(see Section 3.5.7.3).  
3.2.5  
USING RPM4 WITH A PPC3 CONTROLLER/CALIBRATOR  
RPM4 can be integrated as a reference pressure measuring device in a PPC3 Pressure  
Controller/Calibrator System. See the PPC3 Operation and Maintenance Manual for  
information on setting up RPM4 to operate as the PPC3’s external device.  
Before an RPM4 is used with a PPC3, the following settings should be made:  
SDS  
Close SDS on all Q-RPT modules on which SDS is available (see Section 3.2.7).  
Head  
If the RPM4 TEST port is at a different level than the PPC3’s TEST port AND the  
RPM4 will be used in absolute measurement mode, set the RPM4 head height to  
the PPC3’s TEST port level so that RPM4 is corrected to indicate the pressure at  
the level of the PPC3 TEST port (see Section 3.3.7).  
Page 21  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
AutoZ  
Make sure AutoZ is ON for all RPTs and measurement modes (see Section 3.5.1).  
Certain RPM4 settings may be changed when an RPM4 is operated with a PPC3. Settings  
that may be changed when an RPM4 is used as a PPC3 external device include:  
SDS  
Closed or open status may be changed and SDS full time off will be  
overwritten to full time on (see Sections 3.3.8, 3.5.4)  
AutoRange range  
Display  
May be rewritten (see Section 3.3.4).  
When an RPM4 is initialized by PPC3 as an external device, the  
second line of the RPM4 display is <PPC3 EXT DEV: IDLE>. When  
the RPM4 is the active Q-RPT being used by the PPC3, the second  
line of the RPM4 display is <PPC3 EXT DEV: ACTIVE>  
Range  
Active range may be changed (see Section 3.3.1).  
Active unit may be changed (see Section 3.3.2).  
Unit of measure  
Measurement mode Active mode may be changed (see Section 3.3.3).  
Lo Vent  
Setting may be changed (see Section 3.5.7.4).  
Communications  
For a PPC3 to be able to identify and communicate with an RPM4,  
the RPM4’s COM1 port must be set to:  
Baud rate 9200 to 19200  
Parity  
Even  
Data bits  
Stop bit  
7
1
When RPM4 is activated by a a PPC3, the PPC3 sets the RPM4  
COM1 port baud rate to 19200. The COM1 port keeps this setting  
until power is cycled. Cycling power restores the previous baud rate  
setting. The same is true for the COM2 of the first RPM4 in a chain  
of two RPM4s used with a PPC3.  
When RPM4 is initialized as an external device to a PPC3 pressure controller, the RPM4  
front panel keypad is locked out and the second line of the display becomes:  
<PPC3 EXT DEV: IDLE>  
(if RPM4 is initialized by PPC3 but not currently in use)  
<PPC3 EXT DEV: ACTIVE> (if RPM4 is initialized by PPC3 and is currently in use)  
After using an RPM4 as an external device for a PPC3, cycle power to return to the  
previous RPM4 settings, restore front keypad capability and return to the normal main  
run screen.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 22  
3. OPERATION  
3.2.6  
USE OF THE 12VDC BATTERY/CHARGER PACK  
An optional 12VDC battery/charger pack is available to supply power to RPM4s 12VDC  
power connection (see 1.2.3).  
The battery/charger pack combines the battery and the battery charger.  
To Charge the Battery  
The battery may be charged while the battery/charge pack is connected to the RPM4.  
To charge the battery, connect the battery/charger pack to a 100 to 240 V, 50/60 Hz power  
supply using the supplied power cable and turn on the charger power switch. The green  
CHARGE indicator light goes on to indicate that battery charging is in progress. Allow 14 to  
16 hours for the battery to charge fully. When the battery is fully charged, the CHARGE  
indicator light flashes.  
When the battery charger power switch is in the ON, the battery is connected to the charger,  
not the 12VDC output. When the battery charger switch is in the OFF position, the CHARGE  
indicator light goes off, and 12VDC is supplied on the 12VDC connection.  
To Use the Battery/Charger Pack to Supply RPM4  
After charging the battery, connect the 12VDC connection of the battery/charger pack to the  
12VDC connection on the RPM4 rear panel.  
Turn the battery/charger pack power switch to OFF (when AC power is connected to the  
battery/charger pack, the power switch must be OFF for 12VDC power to be output).  
When RPM4 is connected to both a 12 VDC source and an AC source,if the RPM4 power  
switch is OFF, the 12VDC source supplies the RPM4; if the RPM4 power switch is ON, the  
12 VDC source is disconnected and the AC source supplies the RPM4.  
To Check the Battery Charge Level  
To check the current charge level of the battery, press the toggle switch on the  
battery/charger pack front panel. Observe the BATTERY CHECK indicator lights. All three  
lights are lit when battery is fully charged. If no light or one light is on, the battery should be  
recharged.  
Figure 5. Battery Pack/Charger  
Page 23  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
3.2.7  
SDS SELF DEFENSE SYSTEM  
Q-RPT modules designated 7M or lower that are NOT liquid filled are equipped with the SDS self  
defense system. The SDS system includes hardware and embedded software to isolate Q-RPTs  
from overpressure. When SDS is CLOSED for a Q-RPT module, the Q-RPT is isolated from the  
modules TEST(+) port and opened to the modules VENT port (See Section 5.6, Figure 8).  
SDS can be OPENED and CLOSED from the front panel using [SDS]. SDS can also be  
controlled using functions under [SPECIAL], <4SDS>. The SDS “temp open/close” function  
allows SDS on both Q-RPTs, whether active or inactive, to be opened and closed directly  
(see Section 3.5.4.1). The SDS “full time on/off” function allows SDS to be opened permanently  
so the RPM4 can be operated as if SDS were not installed (see Section 3.5.4.2).  
SDS is normally used to isolate an RPM4 Q-RPT from a test system which may sometimes  
be subjected to pressures higher than the Q-RPTs maximum pressure. When configuring a  
multi-range system, this can eliminate the need for external valving or connecting and  
disconnecting RPM4s. For example, two Q-RPTs of different ranges might be connected to  
a single calibration system. When the Hi Q-RPT is in use, SDS is closed on the Lo Q-RPT to  
protect it from overpressure. When used in this manner, SDS should be CLOSED prior to  
applying pressure. Automatic SDS closing in response to overpressure should only be used in  
an emergency overpressure situation.  
SDS also attempts to protect Q-RPTs from accidental overpressure. Whenever RPM4 is  
powered ON it continuously monitors the pressure read by its Q-RPT(s). If the pressure  
reaches the maximum pressure limit for a Q-RPT, SDS CLOSES to isolate the Q-RPT from  
the TEST port and vent it to atmosphere (see Section 3.4.4.1). This is not a fail safe  
overpressure system. It does not protect against very rapid overpressure or pressure  
exceeding 10 MPa (1 500 psi).  
When an RPM4 is used as an external device to a PPC3 pressure controller, PPC3 controls the  
RPM4’s SDS to isolate the RPM4 Q-RPTs from the test pressure when they are not in use.  
IF the RPM4 SDS is “full time off” PPC3 changes it to “ON”.  
The maximum pressure that should be applied to an RPM4 TEST(+) port when SDS is  
CLOSED is 10 MPa (1 500 psi).  
Though the SDS self defense system includes features to automatically protect Q-RPTs  
against accidental overpressure, SDS should NOT be considered a fail-safe overpressure  
protection system. SDS cannot guarantee that overpressure damage will NOT occur.  
Conventional measures for overpressure protection should also always be used. Damage  
to Q-RPTs due to overpressure is NOT covered by the RPM4 product warranty even when  
SDS is present and ON.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 24  
3. OPERATION  
3.2.8  
DIRECT FUNCTION KEYS SUMMARY  
Table 5 provides a brief summary of direct function key operation. It may be useful to keep  
a copy of this summary near the RPM4, especially when first becoming acquainted with  
its operation.  
Local operation of RPM4 is through the front panel keypad. To minimize multi-layered menu  
structures, the keypad numerical keys also provide direct access to the most commonly used  
functions. The function accessed is labeled on the bottom half of the key. Direct function  
keys are active whenever RPM4 is in its MAIN RUN screen. Table 5 summarizes the  
operation of the direct function keys.  
Table 5. Summary of RPM4 Function Key Operation  
DIRECT FUNCTION KEYS ARE ACTIVE FROM THE MAIN RUN SCREEN  
See corresponding manual sections for full detail.  
Adjust height of fluid head  
correction. Set to zero to defeat  
correction.  
View active range and toggle  
through available ranges. [ENT] on  
a range activates it.  
.SDS controls the connection of  
the Q-RPT to the TEST(+) port.  
Close any open SDS. Open SDS  
of active Q-RPT if closed.  
Select pressure unit of measure for  
the active range. Choice of units  
available in this menu can be  
customized.  
Run the AutoZ function to  
AutoZero the active Q-RPT and  
measurement mode.  
Select the pressure measurement  
mode for the active range (absolute,  
gauge, negative gauge, differential).  
Set up and optimize RPM4  
features for a specific operating  
range and measurement mode.  
Menu of less commonly used internal  
functions and settings.  
Menu of commonly used setup  
features  
including  
save/delete  
Run automated leak checking  
routine.  
AutoRange ranges, set display  
resolution, set stability limit, set  
upper/lower, view AutoTest data  
Start or set functions such as Leak  
Check, AutoTest and Freeze.  
ENTER values when editing.  
Select the display function for the  
bottom line of the RPM4 display.  
3.3  
DIRECT FUNCTION KEYS  
3.3.1  
[RANGE]  
 PURPOSE  
To view and/or change the active pressure measurement range and associated settings.  
 PRINCIPLE  
An RPM4 range is defined as a pressure span and associated settings (see Section 3.2.3).  
An RPM4 may have multiple ranges. Each Q-RPT in the RPM4 system has a default range  
which is its maximum span. Additional ranges, lower than the Q-RPT’s maximum span, may  
also be created using AutoRange (see Section 3.3.4). Ranges created using AutoRange  
may be saved, with their settings, for reactivation (see Section 3.4.1).  
The [RANGE] function key allows the available RPM4 pressure ranges to be viewed and selected.  
Page 25  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
 OPERATION  
Pressing the [RANGE] function key activates the range viewing and selecting function.  
When the [RANGE] function key is first pressed, the active range is displayed. For example:  
1. Q-RPT designator.  
2. Type of range. DF for the Q-RPT’s default range; AR for a range  
created by AutoRange.  
Active A700K DF Hi  
psi 100g/100a  
3. Q-RPT position designator.  
4. Current pressure unit of measure.  
5. Full scale pressure in current unit of measure in gauge and/or  
absolute measurement mode depending on type of Q-RPT and range.  
Pressing the [+/-] key or the [RANGE] key again while in the RANGE functions toggles  
through displays of the other available ranges, from lowest range to highest range.  
To select a range to become the active range, press [ENT] while the range is displayed.  
Pressing [ESC] while in the RANGE function returns to the MAIN RUN screen without  
making a range change.  
Range full scale limits are given in the pressure unit that is currently active for that range.  
Pressing [+/-] from the MAIN RUN screen provides a shortcut to a momentary view of the  
active range.  
Many RPM4 settings and functions are range specific. See Table 4 for identification of  
range specific settings.  
For best metrological performance, vent the RPM4 Q-RPT before changing ranges.  
3.3.2  
[UNIT]  
 PURPOSE  
To select the unit of measure in which RPM4 displays pressure values.  
For information on selecting the measurement mode (absolute, gauge, negative gauge,  
differential), see Section 3.3.3.  
 PRINCIPLE  
RPM4 allows the unit of measure in which pressure values are displayed to be changed.  
RPM4 supports 15 standard pressure units of measure as well as user defined units.  
To simplify operation, quick access to six units is made available under the [UNIT] key.  
The default units available depend on whether the RPM4 was originally configured as an SI  
or US version. The [UNIT] key contents can be customized by the user to any configuration  
of six units (see Section 3.5.6).  
© 2004-2007 DH Instruments, a Fluke Company  
Page 26  
3. OPERATION  
Internally, RPM4 always operates in Pascal (Pa), the SI unit of pressure. Values of pressure  
are represented in other units by the application of conversion factors to convert from Pa  
(see Section 7.2.1).  
 OPERATION  
To change the active pressure unit of measure for a  
range, press [UNIT] from the MAIN RUN screen while  
the range is active. The display is:  
1kPa 2Pa 3MPa  
4hPa 5bar 6mbar  
The cursor is on the number corresponding to the active pressure unit of measure for the active range.  
To change the pressure unit of measure, select the desired unit. Making the selection  
returns to the MAIN RUN screen with the selected unit active.  
The pressure unit of measure selected is range specific. When in a given range, all functions  
and settings are represented in the current measurement unit for that range. However,  
certain internal and/or metrological functions (e.g., Q-RPT calibration coefficients) are always  
represented in Pa regardless of the current range unit. When the current unit is an altitude  
unit, the range and upper limit indications are in kPa if the unit is meters (m) and psi if  
the unit is feet (ft).  
See Section 7.2.1 for tables of the conversion factors used by RPM4.  
If the pressure unit selected is inWa (inches of water), the reference temperature for water  
density must we specified in a separate menu (choices are 4ºC, 20ºC 60ºF). No reference  
temperature selection is necessary for the unit mmWa as the only reference temperature  
commonly used for mmWa is 4 ºC.  
The default pressure units of measure available under the UNIT function depend on whether  
the RPM4 has been set up as an SI or US version (indicated by SI or US at bottom right of  
introduction screen). The choice of six units available under the UNIT function can be  
customized from a wider selection by the user (see Section 3.5.6). The units available under  
the UNIT function can be reset to default by reset (see Section 3.5.9.2).  
3.3.3  
[MODE]  
 PURPOSE  
To set the measurement mode (absolute, gauge, negative gauge or differential) for the active range.  
For information on selecting the unit of measure, see Section 3.3.2.  
 PRINCIPLE  
RPM4 supports simple, one-step switching between up to four different measurement modes:  
Absolute  
Measures pressure relative to vacuum (zero is hard vacuum). Range is  
from zero absolute to full scale.  
Page 27  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
Gauge  
Measures pressure relative to atmosphere (zero is ambient pressure).  
Range is from zero gauge to full scale, full scale must be greater than zero.  
Negative Gauge Measures pressure relative to atmosphere (zero is ambient pressure).  
Range is positive and negative from zero, negative to minus one  
atmosphere and positive to full scale. With a BGxxx RPT, negative range  
is the negative equivalent of the positive range.  
Differential  
Available only for the Hi Q-RPT in RPM4s equipped with two Q-RPT modules  
of the same type (Axxx, Gxxx, BGxxx). Measures the difference between the  
Hi and the Lo Q-RPT (Differential = Hi – Lo). Differential measurement mode  
is selected “on top of” the Hi Q-RPT’s base measurement mode (gauge,  
absolute or differential). Differential range is positive to maximum pressure of  
the Hi Q-RPT and negative to the minimum pressure of the Lo Q-RPT base  
measurement mode (see Section 3.3.3.1 for specific information on operation  
in differential measurement mode).  
Which measurement modes are available depends on the type of Q-RPT type(s) available.  
There are three types of Q-RPTs:  
Axxx  
Q-RPTs with designators starting with “A” measure pressure relative to a sealed  
vacuum reference and are intrinsically absolute. Axxx Q-RPTs support  
measurement in absolute, gauge and negative gauge modes. Gauge and negative  
gauge modes are accomplished by offsetting of atmospheric pressure with  
dynamic compensation for atmospheric pressure changes between offsets using  
an on-board barometer (see Section 3.2.2). Access to absolute and negative  
gauge operation can be turned OFF (see Section 5.2.5). In RPM4s with two Axxx  
Q-RPTs, differential measurement mode is supported on the Hi Q-RPT.  
Gxxx  
Q-RPTs with designators starting with “G” measure positive pressure relative to the  
TEST(-) port that is connected to atmosphere. Gxxx Q-RPTs support measurement  
in gauge mode only. In RPM4s with two Gxxx Q-RPTs, differential measurement  
mode is supported on the Hi Q-RPT.  
BGxxx Q-RPTs with designators starting with “BG” measure positive and negative  
pressure relative to the TEST(-) port that is connected to atmosphere. BGxxx Q-RPTs  
support measurement in gauge and negative gauge modes. In RPM4s with two  
BGxxx Q-RPTs, differential measurement mode is supported on the Hi Q-RPT.  
When changing modes for a range, if the full scale of the range is 700 kPa (100 psi) or  
greater, the full scale is the same in both absolute and gauge modes. If the full scale is less  
than 700 kPa (100 psi), the gauge mode full scale is 100 kPa (14.5 psi) lower than the  
absolute mode full scale. If the absolute mode full scale is less than 100 kPa (14.5 psi), there  
is no gauge mode available. Gauge and negative gauge modes, when available, always  
have the same full scale.  
Measurement mode selection is range specific.  
 OPERATION  
See Section 3.3.3.1 for information on differential mode operation. Differential mode  
operation is only available for the Hi Q-RPT in RPM4s that are equipped with two Q-RPTs  
of the same type (Axxx, Gxxx, BGxxx).  
To change the active measurement mode for a range,  
Measurement mode:  
press [MODE] from the MAIN RUN screen while the  
range is active. The display depends upon the type of  
Q-RPT that is active.  
1abs 2gage 3neg gage  
© 2004-2007 DH Instruments, a Fluke Company  
Page 28  
3. OPERATION  
If an Axxx Q-RPT is active, all thee measurement modes are supported: absolute, gauge  
and negative gauge. Only gauge is available if absolute and negative gauge modes have  
been turned OFF in calibration (see Section 5.2.5).  
If a Gxxx Q-RPT is active, only gauge measurement mode is supported. When the [MODE]  
key is pressed, <Gauge RPT, gauge mode only> is displayed.  
If the Hi Q-RPT is active in its default range (<DF>), and the RPM4 has two Q-RPTs of the  
same type (Axxx, Gxxx, BGxxx), differential measurement mode is available in addition to the  
other modes (see Section 3.3.3.1).  
Certain RPM4 settings, including AutoZ ON/OFF (see Section 3.5.1) are range AND measurement  
mode specific. See Table 4 for a listing of settings and what they are specific to.  
Absolute and negative gauge modes on an Axxx Q-RPT can be turned OFF in the  
calibration function (see Section 5.2.5). When absolute and negative gauge mode are  
turned OFF for an Axxx Q-RPT, only gauge mode can be activated. <Gauge mode only,  
other modes OFF> is displayed when [MODE] is pressed.  
3.3.3.1  
DIFFERENTIAL MEASUREMENT MODE OPERATION  
Differential mode operation is only available on the Hi Q-RPT, default  
(<DF>) range, in RPM4s that are equipped with two Q-RPTs (Hi and Lo) of  
the same type (Axxx, Gxxx, BGxxx).  
To activate differential measurement mode, press [MODE] from the MAIN RUN  
screen while the Hi Q-RPT is active and in its default (<DF>) range. The actual  
display depends upon the measurement modes available on the Hi Q-RPT.  
The cursor is on the base measurement  
mode. The line pressure measurement mode  
is the base pressure measurement mode.  
Meas mode: 1abs  
2gage 3neg gage 4dif  
To activate differential measurement mode, press the keypad number key for the  
<dif> selection or move the cursor to the <dif> selection and press [ENT].  
Operation returns to the main run screen. When differential mode is active,  
the cursor is on both the base mode and differential mode.  
When differential mode is active, the Q-RPT position indicator is in the upper  
right hand corner of the main run screen and other displays is <Hd> instead  
of <Hi> (see Section 3.2.3, Table 3).  
When differential mode is activated, AutoZ should be run at the line pressure  
with zero differential pressure applied to eliminate the zero error on differential  
pressure due to the disagreement of the Hi and Lo Q-RPTs (see Section 3.3.9.3).  
Page 29  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
The following operating conditions are specific to differential mode:  
Main run screen measured pressure display  
The display of measured pressure in the main run  
screen is the difference between the Hi and the Lo  
Q-RPTs (Hi – Lo) with a differential mode AutoZ  
correction (see Section 3.3.9.3).  
The pressure  
measurement mode indicator is <d>. The Q-RPT  
position indicator is <Hd>.  
Default DISPLAY function The default display function is RPT with the Lo Q-RPT  
displayed on the bottom display line (see Section  
3.3.6.4). This allows the line pressure (Lo Q-RPT  
indication) to be viewed simultaneously with the  
differential pressure. All other DISPLAY functions  
(average, rate, deviation, HiLo, freeze) apply to  
the differential pressure  
SDS function  
[SDS] key operation to OPEN SDS opens SDS of  
both the Hi and Lo Q-RPTs simultaneously. (see  
Section 3.3.8). Overpressure is driven by the pressure  
range of the Lo Q-RPT (see Section 3.4.4.1).  
AutoZ function  
AutoZ manages zeroing of differential mode and is  
intended to “tare” the two Q-RPTs at a common  
line pressure (see Section 3.3.9.3). Switch to a  
mode other than differential for AutoZ functions of  
an individual Q-RPT.  
Leak Check function  
Head function  
The leak check function uses the differential mode  
measurement (see Section 3.3.5).  
The head function applies to the differential  
pressure (see Section 3.3.7).  
AutoRange function  
UL function  
Differential measurement mode is not available in  
AutoRange (see Section 3.3.4).  
The UL limits apply to positive and negative  
differential pressure (see Section 3.4.4) and the  
default is the maximum value of the differential  
pressure.  
Both the Lo and Hi RPT base  
measurement mode ULs also remain active. The  
Hi RPT UL provides a upper limit for the maximum  
pressure on the Hi side of the differential pressure.  
Both the differential and base mode Hi RPT UL  
cause the display of differential pressure to flash  
when exceeded. The Lo RPT UL provides an  
upper limit for the line pressure.  
AutoTest function  
The AutoTest function (see Section 3.3.10) is not  
available in differential measurement mode.  
3.3.4  
[AUTORANGE]  
 PURPOSE  
To automatically set up RPM4 to optimize its measurement characteristics and features for  
specific, user specified range of operation.  
 PRINCIPLE  
RPM4 is designed to support the calibration and test of a very wide variety of test ranges in  
various measurement modes.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 30  
3. OPERATION  
The AutoRange function simplifies the task of selecting the Q-RPT best suited to cover a  
specific test range and setting measurement parameters appropriately for the range. These are  
set automatically based on operator entry of desired measurement mode, pressure unit of measure  
and range full scale. The selections and settings made by AutoRange are summarized in Table 6.  
A range set up using AutoRange and all its range specific settings, may be saved for recall  
using [SETUP], <1range> (see Section 3.4.1). Saved ranges are available for later selection  
using [RANGE] (see Section 3.3.1). If a range created by AutoRange is not saved, it is  
overwritten by the next AutoRange or erased when another range is selected.  
Press [ENT] from the main run screen in RATE mode to use the [AutoTest] function to  
AutoRange RPM4 based on DUT tolerance (see Section 3.3.10).  
Table 6. Settings Made by AutoRange  
SETTING/SELECTION  
PURPOSE  
SET TO  
SECTION  
Unit  
Set pressure unit of measure  
Operator specified during  
AutoRange  
3.3.2  
Mode  
Set pressure measurement mode  
(absolute, gauge, negative gauge)  
Operator specified during  
AutoRange  
3.3.3  
None  
None  
Full scale  
Establish span maximum  
Operator specified during  
AutoRange  
AutoRange span  
Basis of span based setting  
calculations  
Absolute mode: Zero absolute  
to AutoRange full scale  
Gauge mode: Zero gauge to  
AutoRange full scale  
Negative gauge mode: Minus  
atmosphere to AutoRange full  
scale (negative equivalent of full  
scale on BG15K Q-RPT).  
Q-RPT  
Select most appropriate Q-RPT  
to cover range and mode.  
1.2.2.1  
Absolute and negative gauge  
mode: Axxx Q-PRT with lowest  
default full scale that is greater  
than the AutoRange full scale  
Gauge mode: Q-RPT with  
lowest span whose full scale is  
greater than AutoRange full  
scale, Gxxx over Axxx if spans  
are equal.  
Upper limit  
Lower limit  
Set maximum and minimum  
pressure alarm limits.  
3.4.4  
Upper limit: 105 % of operator  
entered full scale pressure  
Lower limit: None in absolute  
and gauge modes. Minus  
atmosphere in negative gauge  
mode, minus equivalent of upper  
limit in negative gauge mode on  
a BG15K Q-RPT. Minus 66 kPa  
(9.6 psi) with BA100K.  
Resolution  
Set display resolution  
10 ppm of AutoRange span or  
1 ppm of default Q-RPT span,  
whichever is larger.  
3.4.2  
Stability Limit  
Set Ready/Not Ready stability  
criterion.  
50 ppm of AutoRange span or 2  
ppm of default Q-RPT span,  
whichever is larger.  
3.4.3,  
3.3.4  
Q-RPT turn down  
(Premium class Q-RPTs only)  
Turn down Q-RPT  
See RPM4 pressure  
measurement specifications  
1.2.2.1  
characterization to improve  
measurement uncertainty when  
span is reduced  
Page 31  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
 OPERATION  
To use the AutoRange function, press [AutoRange] and respond to the RPM4’s prompts.  
Select AutoRange measurement mode: The screen is identical in appearance and  
function to the [MODE] screen (see Section 3.3.3). The choice of measurement modes  
offered reflects all the Q-RPT types available (Axxx, Gxxx, BGxxx) in the RPM4 system,  
not just the active Q-RPT.  
Differential pressure measurement mode (see Section 3.3.3.1) is not available in  
AutoRange.  
Select pressure unit of measure: The screen is identical in appearance and function  
to the [UNIT] screen (see Section 3.3.2).  
Altitude units of measure (m, ft) are not available for AutoRange.  
Enter the AutoRange full scale pressure: Enter the full scale pressure value in the  
<------> entry field and press [ENT]. If the full scale value entered cannot be covered by  
any of the Q-RPTs available, an error message appears. If the full scale value can be  
covered, AutoRange proceeds to the range display.  
View proposed AutoRange range: The proposed AutoRange range screen is:  
1. Indication that this is a screen of the proposed AutoRange range.  
2. Designator and position of the Q-RPT that AutoRange has selected  
to cover the AutoRange full scale and measurement mode.  
3. Pressure unit of measure specified in AutoRange.  
AutoRange A700K Hi  
kPa 300g/100a  
4. AutoRange full scale pressure in gauge mode and absolute  
mode if available. Absolute mode only if AutoRange measurement  
mode is absolute and full scale is less than 100 kPa (14.5 psi).  
Gauge mode only if the Q-RPT is a Gxxx or BGxxx or an Axxx  
with absolute mode turned off.  
If the RPM4 has two Q-RPTs and you would like to select the other one for the  
AutoRange, the cursor control keys may be used to toggle between Q-RPTs selections if  
both Q-RPTs can handle the specified AutoRange.  
Accept proposed AutoRange: To accept the proposed AutoRange and go to the MAIN  
RUN screen with the AutoRange range active, press [ENT] or [AutoRange]. To modify  
the AutoRange full scale, measurement mode or pressure unit of measure, use [ESC] to  
back through the AutoRange screens and make changes.  
To verify or confirm the range from the MAIN RUN screen, use [+/-] or [RANGE] to  
view the active range (see Section 3.3.1).  
See Table 6 for a listing of all selections and settings affected by AutoRange and  
their default values.  
The BA100K Q-RPT cannot be AutoRanged.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 32  
3. OPERATION  
3.3.5  
[LEAK CK]  
 PURPOSE  
To run an automated leak check routine that determines the leak rate of the system  
connected to the RPM4 active Q-RPT TEST(+) port.  
 PRINCIPLE  
The LEAK CHECK function is provided as a means of checking and quantifying the leaks that  
may be present in the system connected to the RPM4’s active Q-RPT test port.  
The principle of the LEAK CHECK function is the measurement of the natural decrease or  
increase of pressure in a fixed volume over time. The LEAK CHECK function allows a leak  
check time to be set. The total pressure change and the average rate of change over the  
leak check time are calculated and displayed.  
In differential pressure measurement mode (see Section 3.3.3.1), the leak check  
measurement is based on the measurement of the differential pressure.  
 OPERATION  
To run a leak check, first set the pressure to the desired leak check pressure.  
Changing the pressure in a test system causes adiabatic temperature changes in the  
pressurized medium that need to have dissipated before a valid leak measurement can be  
made. In general, a 0.5 to 1 minute wait before running a leak check is adequate to allow  
the adiabatic temperature change to dissipate and valid leak measurements to be made.  
However, stabilization time may be much longer with liquid test media, and as volume and  
pressure increases.  
To access the LEAK CHECK function, press [LEAK CHECK] from the MAIN RUN screen.  
Select <1run> to run a leak test. The display is:  
Set leak check time:  
1. Edit field for the time over which the leak rate will be  
15 s  
determined, in seconds.  
Edit the leak check time if desired (minimum 1, maximum 999 seconds) and press [ENT].  
Press [ENT] again when ready to start the leak test. The leak test display is:  
1. Standard MAIN RUN screen first line showing measured  
pressure.  
957.84 kPa a  
Leak testing  
Hi  
2. Active Q-RPT position indicator  
13 s  
3.  
Indication that leak test is running and countdown of time  
remaining.  
Page 33  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
[ESC] can be used to abort the running leak test. [ENT] while the leak test is running  
restarts the leak check timer. When the leak check timer countdown has completed,  
RPM4 beeps three times and the leak check results screen is displayed:  
1. Total pressure change from start to finish of leak check time.  
P 0.61 kPa a Hi  
2. Indicator of Q-RPT used to run the leak check.  
Rate 0.06 kPa/sec  
3. Average rate of change of pressure over the leak check  
time period (P/time in seconds).  
From the leak check results screen, press [ENT] to repeat the leak test.  
Press [ESC] to return to leak check main menu and exit to the MAIN RUN screen.  
To view the results of the most recently completed leak check, press <2view>. If NO leak  
check data is stored (i.e., if the RPM4 has never run a leak test or a reset has cleared  
previous leak test results), the results screen displays <Data NOT available> briefly and  
returns to MAIN RUN screen. Press [ENT] or [ESC] to return to the MAIN RUN screen.  
Leak check is range specific in the sense that a leak check is run using the active range.  
However, only one set of leak check results is maintained in memory and each leak test  
completed overwrites the memory. View leak check always shows the results of the last  
leak check run regardless of the range that is now active. The results screen includes the  
range indicator to indicate the range in which the leak check was run.  
3.3.6  
[DISPLAY]  
 PURPOSE  
To select, from a variety of choices, the information that is displayed on the second line of the  
RPM4 display.  
 PRINCIPLE  
RPM4 supports a variety of advanced pressure measurement functions that are displayed on  
the second (bottom) line of the RPM4 display. In summary, the available display functions  
included are:  
AVERAGE  
Calculates the average pressure measurement over a user specified period  
of time and displays the average, the standard deviation about the mean and  
a countdown in seconds to the next average (see Section 3.3.6.1). This function  
is often used to filter out pressure noise in an unstable system. The magnitude  
of the noise is quantified by the standard deviation about the mean. A second  
Avg screen allows the instantaneous pressure values to be viewed during an  
averaging cycle.  
RATE  
Calculates and displays the current rate of change of pressure in current  
pressure units/second (see Section 3.3.6.2). This function is a useful  
indication of the stability of the pressure being measured. It is often used as  
an indication of positive or negative leak rate and as a go/no go criterion of  
when to take data when comparing RPM4 and a device under test, for  
example in a calibration. Rate is used by the Ready/Not Ready function to  
determine when a Ready condition exists (see Section 3.2.1).  
DEVIATION  
Continuously calculates and displays the difference between the pressure  
measured by RPM4 and a target pressure entered by the user (see Section  
3.3.6.3). This function is useful in monitoring the evolution of pressure around  
and/or away from a desired set point.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 34  
3. OPERATION  
RPT  
If the RPM4 has two Q-PRTs, allows pressure measurement from the two  
RPTs to be displayed simultaneously (see Section 3.3.6.4). This function is  
particularly useful in dual Q-RPT RPM4s with independent TEST ports to  
monitor two separate pressures simultaneously. It is also used to when the  
Hi Q-RPT is in differential measurement mode, to observe the line pressure  
measured by the Lo Q-RPT.  
HI/LO  
Records and displays maximum and minimum pressures measured (see  
Section 3.3.6.5). This function is used to keep track of the minimum and  
maximum pressure observed in a system over a period of time or to monitor  
if a pressure min/max limit has been exceeded..  
FREEZE  
Captures and displays the pressure measured by the active range of RPM4  
when the [ENT] key is pressed (see Section 3.3.6.6). This function is useful  
to record the pressure present at the time of an operator observed trigger  
event, for example when the needle of an analog gauge was on the nominal  
point or when a switch activates.  
CLEAN  
Blanks out the second line of the display (see Section 3.3.6.7). This function  
is used when a simple display of pressure measured by the RPM4 active  
range without additional information is desired.  
 OPERATION  
To set the DISPLAY function press [DISPLAY] from the main run screen.  
1avg 2rate 3dev 4RPT  
5HiLo 6freeze 7clean  
The display is:  
The cursor is on the active DISPLAY function. Selecting a display function returns to the  
main run screen with the selected function active.  
Display menu choices include:  
<1avg>  
Display average pressure and standard deviation. Specify averaging time period  
(see Section 3.3.6.1).  
<2rate>  
<3dev>  
Display pressure rate of change (see Section 3.3.6.2).  
Display deviation of the measured pressure from a target value and specify  
the target value (see Section 3.3.6.3).  
<4RPT>  
Display the pressure measured by the second Q-RPT in RPM4s with two  
Q-RPTs (see Section 3.3.6.4).  
<5HiLo>  
<6freeze>  
<7clean>  
Display the maximum and minimum pressure observed since HiLo reset  
(see Section 3.3.6.5).  
Capture and display the value measured when [ENT] is pressed  
(see Section 3.3.6.6).  
Leave the second line of the display blank (see Section 3.3.6.7).  
The DISPLAY selection is NOT range specific. A DISPLAY selection made in one range  
applies to all ranges.  
The default DISPLAY function is Rate which causes the second line of the display to show “R”  
followed by the current rate of change of pressure in current pressure units per second.  
The default DISPLAY function in differential mode is RPT.  
Page 35  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
When RPM4 is initialized as an external device to a PPC3 pressure controller, the RPM4  
front panel keypad is locked out and the second line of the display becomes:  
<PPC3 EXT DEV: IDLE> (if RPM4 is initialized by PPC3 but not currently in use)  
<PPC3 EXT DEV: ACTIVE> (if RPM4 is initialized by PPC3 and is currently in use)  
After using an RPM4 as an external device for a PPC3, cycle power to return to the  
previous RPM4 settings, restore front keypad capability and return to the normal main  
run screen.  
3.3.6.1  
AVG (AVERAGE)  
 PURPOSE  
To activate the Average DISPLAY and/or adjust the period of time over which  
averaging occurs.  
See Section 3.3.6.  Principle.  
 OPERATION  
To access the Average DISPLAY, press [DISPLAY], <1Avg>. The display is:  
Averaging Period:  
1. Edit field for averaging period in seconds.  
20 s  
Default is 20. Minimum 1, maximum 999.  
Edit the averaging time period if desired. Pressing [ENT] returns to the main run  
screen with the Average DISPLAY active.  
With the Average DISPLAY active the main run screen is:  
1. Average measured over last completed  
averaging period.  
96.929 kPa a  
Hi  
2. Standard deviation of last completed  
averaging period.  
δ 0.0007  
18Avg  
3. Countdown in seconds until completion of on-  
going averaging period.  
The Average DISPLAY has a second screen that allows the instantaneous  
pressure readings to be viewed while an averaging cycle is running.  
The instantaneous Average screen is:  
1. Instantaneous pressure values at RPM4’s  
normal update rate.  
96.929 kPa a  
Hi  
18Avg  
2. Current rate of change of pressure in pressure  
units/second.  
R 0.0025  
3. Countdown in seconds until completion of on-  
going averaging period.  
The [+/-] key toggles between the main run Average screen and the  
instantaneous values Average screen.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 36  
3. OPERATION  
Pressing [ENT] while in the Average DISPLAY aborts the current averaging  
period and causes a new one to begin. [ENT] can thus be use to trigger a  
new averaging period on demand.  
In the Average DISPLAY the Ready/Not Ready indication applies to the result  
of the previous averaging period (see Section 3.2.1). <Ready> indicates that  
all readings during the previous averaging period met the stability criterion.  
<Not Ready> indicates that one or more readings were outside of the  
stability criterion.  
Changing the pressure unit of measure, measurement mode or range while  
the averaging screen is active, starts a new averaging period.  
To go to a DISPLAY other than Average, press [DISPLAY] and make a new  
DISPLAY choice (see Section 3.3.6).  
3.3.6.2  
Rate  
 PURPOSE  
To activate the Rate DISPLAY.  
See Section 3.3.6 [DISPLAY],  Principle.  
The AutoTest function (see Section 3.3.10) to AutoRange RPM4 based on  
DUT characteristics and run an automated test sequence is accessed by  
pressing [ENT] from the Rate run screen.  
 OPERATION  
To activate the Rate DISPLAY press [DISPLAY], <2Rate>. Pressing <2Rate>  
returns to the main run screen with the Rate DISPLAY active.  
With the Rate DISPLAY active the main run screen is:  
99.1135 psi a Hi  
1. Current rate of change of pressure in current  
R 0.0001/sec  
pressure units per second.  
The Rate DISPLAY is different and separate from the stability setting which  
is used to set the stability criterion on which the Ready/Not Ready  
indication is based (see Sections 3.4.3 and 3.2.1). The Rate DISPLAY only  
causes the current rate of change to be displayed and has NO affect on the  
stability setting or the Ready/Not Ready condition.  
Page 37  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
The Rate DISPLAY is the default display except in differential measurement  
mode in which the default DISPLAY is RPT.  
To go to a DISPLAY other than Rate, press [DISPLAY] and make a new  
DISPLAY choice (see Section 3.3.6).  
3.3.6.3  
Dev (Deviation)  
 PURPOSE  
To activate the Deviation DISPLAY and/or set the deviation target value.  
See Section 3.3.6 [DISPLAY],  Principle.  
 OPERATION  
Target:  
To activate the Deviation DISPLAY press  
[DISPLAY], <3Dev>. The display is:  
100.0000 psi a  
Edit the desired target value. Pressing [ENT] returns to the main run screen with  
the Deviation DISPLAY active using the entered target value.  
The target value is the value from which deviations (D) are measured by the  
Deviation DISPLAY following:  
D = current pressure - target pressure  
With the Deviation DISPLAY active the main run screen is:  
99.1135 psi a zH3  
1. Deviation of current pressure from the target  
value.  
D -0.8865 T100.0000  
2. Target value.  
Pressing [ENT] from the main run screen when the Deviation DISPLAY is  
active goes directly to the Target editing screen. This allows the target  
value to be changed without going through the DISPLAY menu.  
If the pressure measurement unit or mode is changed while the Deviation  
DISPLAY is active the target value remains at the same numerical value.  
It is NOT converted.  
To go to a DISPLAY other than Deviation, press [DISPLAY] and make a new  
DISPLAY choice (see Section 3.3.6).  
© 2004-2007 DH Instruments, a Fluke Company  
Page 38  
3. OPERATION  
3.3.6.4  
RPT  
 PURPOSE  
To activate the RPT DISPLAY.  
See Section 3.3.6,  Principle.  
The RPT DISPLAY is only available in RPM4s with two Q-RPTs.  
 OPERATION  
For the sake of clarity, when describing the RPT DISPLAY, the Q-RPT  
displayed on the top line of the display when the RPT function is selected is  
referred to as the “active” Q-RPT. The other Q-RPT to be displayed on the  
second (bottom) line of the RPM4 display is referred to as the “inactive”  
Q-RPT. It is “inactive” in the sense that all RPM4 functions and settings  
such as UNIT and RES still apply to the “active” Q-RPT. To make changes to  
the “inactive” Q-RPT, for example to change its measurement units, it must  
be made the active Q-RPT by a conventional range change (see Section 3.3.1).  
In differential pressure measurement mode, the Hi Q-RPT is always the  
“active” Q-RPT.  
To activate the RPT DISPLAY, press [DISPLAY], <4RPT>. Operation returns to  
the MAIN RUN screen with the inactive Q-RPT displayed on the display’s bottom  
line. The range of the inactive Q-RPT is always the default range, not an  
AutoRanged range (see Section 3.3.4).  
If the RPM4 has only one Q-RPT, <Not available with single RPT> displays  
momentarily and operation returns to the main run screen when [DISPLAY],  
<4RPT> is pressed.  
If the RPM4 is in parallel (<HL>) (see Section 3.5.7.3) mode in which both  
Q-RPTs are used simultaneously, when <4RPT> is selected, the Q-RPT to display  
on the lower display line must be specified. The Q-RPT specific settings of the  
Q-RPT displayed in the lower display line (measurement mode, unit of measure,  
resolution, etc.) can only be changed by making that Q-RPT active.  
With the RPT DISPLAY active the main run screen is:  
1. Active RPT display.  
99.1135 psi a zHi  
2. Inactive RPT display with Ready/Not Ready  
*2350.23 psi g zLo  
indicator on far left.  
Page 39  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
If the inactive RPT is equipped with SDS Self Defense System (see Section  
3.2.7), SDS will almost certainly be CLOSED when the RPT DISPLAY is activated.  
SDS can be OPENED on the inactive RPT using [SPECIAL], <4SDS> (see Section  
3.5.4). In differential or parallel measurement mode, SDS can be opened  
simultaneously on both Q-RPTs using [SDS] (see Section 3.3.8).  
The RPT DISPLAY is the default display in differential measurement mode.  
When the RPT display is active, executing a range change to a range on the  
inactive Q-RPT makes the inactive Q-RPT the active Q-RPT. The DISPLAY  
defaults back to Rate ( Section 3.3.6.2).  
To go to a DISPLAY other than RPT, press [DISPLAY] and make a new  
DISPLAY choice (see Section 3.3.6).  
3.3.6.5  
Hi/Lo  
 PURPOSE  
To activate the Hi/Lo DISPLAY.  
See Section 3.3.6,  Principle..  
 OPERATION  
To activate the Hi/Lo DISPLAY press [DISPLAY], <5Hi/Lo>. Pressing <5Hi/Lo>  
resets the Hi/Lo values and returns to the main run screen with the Hi/Lo  
DISPLAY active.  
With the Hi/Lo DISPLAY active the main run screen is:  
99.1135 psi a zHi  
1. Highest pressure observed since Hi/Lo reset.  
H 99.2254 L98.0098  
2. Lowest pressure observed since Hi/Lo reset.  
The Hi/Lo values change each time a new Hi or Lo pressure is observed.  
The Hi/Lo record can be reset at any time by pressing [ENT]. This allows a  
Hi/Lo reset without going back through the DISPLAY menu.  
If the pressure measurement unit, mode or range is changed while the Hi/Lo  
DISPLAY is active, Hi/Lo resets.  
To go to a DISPLAY other than Hi/Lo, press [DISPLAY] and make a new  
DISPLAY choice (see Section 3.3.6).  
© 2004-2007 DH Instruments, a Fluke Company  
Page 40  
3. OPERATION  
3.3.6.6  
Freeze  
 PURPOSE  
To activate the Freeze DISPLAY.  
See Section 3.3.6,  Principle.  
 OPERATION  
To activate the Freeze DISPLAY press [DISPLAY], <6Freeze>. Pressing  
<6Freeze> returns to the main run screen with the Freeze DISPLAY active.  
With the Freeze DISPLAY active the main run screen is:  
99.135 psi a zHi  
1. Pressure measured by active range of RPM4  
when [ENT] was pressed (displays 0.00 by  
default when Freeze DISPLAY is first  
activated).  
F 99.2133  
Pressing [ENT] causes the current pressure measured by the active RPM4 Q-RPT  
to be captured and displayed.  
If the pressure measurement unit, mode or range is changed while the Freeze  
DISPLAY is active, the Freeze value defaults back to zero.  
To go to a DISPLAY other than Freeze, press [DISPLAY] and make a new  
DISPLAY choice (see Section 3.3.6).  
3.3.6.7  
Clean  
 PURPOSE  
To activate the Clean DISPLAY.  
See Section 3.3.6,  Principle..  
The AutoTest function (see Section 3.3.10) to AutoRange RPM4 based on  
DUT characteristics and run an automated test sequence is accessed by  
pressing [ENT] from the Rate run screen.  
Page 41  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
 OPERATION  
To activate the Clean DISPLAY press [DISPLAY], <7Clean>. Pressing <7Clean>  
returns to the main run screen with the Clean DISPLAY active.  
With the Clean DISPLAY active the main run screen is:  
1. Conventional main run screen first line.  
99.135 psi a zHi  
2. “Clean” second line.  
To go to a DISPLAY other than Clean, press [DISPLAY] and make a new  
DISPLAY choice (see Section 3.3.6).  
3.3.7  
[HEAD]  
 PURPOSE  
To cause a pressure fluid head correction to be added to or subtracted from the pressure  
measured by the RPM4 reference pressure transducer in order to predict the pressure at a  
height other than the RPM4’s reference level.  
 PRINCIPLE  
RPM4 measures gauge or absolute pressure at the height of the rear panel TEST(+) port.  
Frequently, when performing a calibration or test, the device or system under test is at a  
different height than the RPM4’s TEST(+) port. This difference in height, frequently called  
head, can cause a significant difference between the pressure measured by the RPM4 at its  
TEST(+) port height and the pressure actually applied to the device under test which is at a  
different height. In this case, it is useful to make a head correction to the pressure measured  
by the RPM4 in order to predict the pressure actually applied at a different height.  
RPM4 can accurately determine “head” pressures for gases (nitrogen, helium and air) and  
liquids (oil, water) as the pressurized medium. In calculating the head value, standard gravity  
(9.80665 m/s2) is used. Gas densities are calculated from the selected gas’s standard  
density correcting for temperature of 20°C and the measured pressure using the gas’s  
compressibility factor to 100 MPa (15 000 psi) and extrapolated above 100 MPa. Oil density  
is taken to be 850 kg/m3, the density of typical calibration oils at 20°C. Water density is taken  
to be 998.2321kg/m3 (20°C). A custom liquid density may also be specified.  
The [HEAD] function key is used to specify the height difference between the RPM4 TEST(+)  
port and another height. Entering a height of zero turns the function off. The height unit and  
the test fluid are specified by pressing [SPECIAL], <3Head> (see Section 3.5.3).  
Use of the HEAD function to assure in tolerance measurements is most important in low  
absolute pressure ranges. Specifying the head height within ± 5 cm (2.5 in.) is adequate  
to assure that, even in the worst case, the uncertainty on the head correction will be  
insignificant relative to the tolerance on the measurement.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 42  
3. OPERATION  
 OPERATION  
To access the HEAD function, press [HEAD]. The display is:  
Edit head height:  
+ 25 cm N2  
1. Test fluid currently specified for the head correction.  
2. Edit field for head height.  
Edit the head height to the desired value. Press [ENT] to return to the MAIN RUN screen  
with the new head correction active. Press [ESC] to return with no changes.  
The reference height of the RPM4  
pressure measurement is the middle of  
the RPM4 TEST port. The head height  
should be entered as a positive value if  
the device or system under test is  
higher than the RPM4 and negative if it  
is lower.  
The HEAD function is NOT range specific. The HEAD ON or OFF status remains the same  
as Q-RPTs and ranges are changed. Edits made to the head settings are independent of  
active range or Q-RPT.  
When a head correction is being applied, it is indicated by <h> in the top line of the MAIN  
RUN screen (see Section 3.1.1). When the head correction is zero, the <h> is not shown.  
To change units of head height between inches and centimeters and to change the test  
fluid species, use [SPECIAL], <3head> (see Section 3.5.3).  
3.3.8  
[SDS] (SELF DEFENSE SYSTEM)  
 PURPOSE  
To CLOSE SDS on all reference pressure transducers (Q-RPTs). To OPEN SDS on the  
active Q-RPT.  
SDS is present only on Q-RPTs designated A7M or lower.  
The [SDS] key should be used with care to avoid accidentally overpressuring a Q-RPT.  
Always double check to ensure that the pressure applied to the Q-RPT’s TEST port is  
lower than the Q-RPT’s maximum pressure before OPENING SDS.  
SDS can be set to permanently be OPEN as if no SDS were installed (see Section  
3.5.4.2).  
Page 43  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
 PRINCIPLE  
SDS is a self defense system to protect RPM4 Q-RPTs from overpressure. SDS CLOSES  
automatically to protect a Q-RPT that is not active. In a two Q-RPT RPM4, activating one  
Q-RPT automatically CLOSES SDS on the other Q-RPT. Powering down the RPM4 or  
energizing it also CLOSES SDS on all Q-RPTs.  
When a Q-RPT’s module’s SDS is CLOSED, the Q-RPT is isolated from the TEST(+) port  
and opened to the VENT port. SDS must be OPENED for the pressure applied to the  
TEST(+) port to be measured. The [SDS] key is used to OPEN SDS.  
The SDS function can also be used to CLOSE SDS as might be desired when leaving RPM4  
at rest or when a possible overpressure situation is anticipated. Pressing [SDS] always  
CLOSES any SDS systems that are OPEN.  
See Section 3.2.7 for general information on SDS and its principles and Section 5.6,  
Figure 8 for Q-RPT module schematics.  
SDS closed is indicated by <SDS CLOSED> flashing in the current measured pressure  
display field. When SDS is closed, the Q-RPT is isolated from the TEST(+) port and  
connected to the VENT port.  
 OPERATION  
Though the SDS self defense system includes features to protect Q-RPTs against  
overpressure, SDS should NOT be considered a fail-safe overpressure protection system.  
SDS cannot guarantee that overpressure damage will NOT occur. SDS closing automatically  
may protect an RPT in case of accidental overpressure but conventional measures for  
overpressure protection should always be used. Damage to Q-RPTs due to overpressure  
is NOT covered by the RPM4 product warranty even when SDS is present and ON.  
The maximum pressure that should be applied to an RPM4 TEST(+) port when SDS is  
CLOSED is 10 MPa (1 500 psi).  
When SDS is CLOSED with a pressure applied, a valve shuts isolating the Q-RPT from the  
TEST(+) port. Another valve vents the Q-RPT to atmosphere through the VENT port.  
If the pressure applied at the time SDS is CLOSED is less than 1 700 kPa (250 psi),  
the VENT valve will open causing sudden release of pressure through the VENT port and  
returning the Q-RPT to atmospheric pressure. If the pressure applied at the time SDS is  
CLOSED is greater than 1 700 kPa, the VENT valve may NOT open. In this case, to vent  
pressure from the Q-RPT module, remove the pressure from the TEST(+) port. This will  
cause the SDS TEST port isolation valve to open partially, reducing pressure under  
1 700 kPa at which time the SDS VENT valve will open (see Section 5.6, Figure 8)  
Pressing [SDS] always CLOSES any SDS system that is OPEN. In a dual Q-RPT RPM4,  
even if the active Q-RPT has NO SDS, pressing [SDS] CLOSES SDS for the inactive Q-RPT  
if SDS is present.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 44  
3. OPERATION  
Use [SDS] to OPEN SDS if it is CLOSED for the active Q-RPT and/or to CLOSE SDS for the  
active and inactive Q-RPT.  
When [SDS] is pressed, there are three possible results depending whether the active Q-RPT is  
SDS equipped and ON (see Section 3.5.4.2), and whether its SDS is OPEN or CLOSED.  
1. If the active Q-RPT IS NOT SDS equipped or its SDS if “full time OFF” (see Section 3.5.4.2):  
<No SDS on RPT> or <SDS is OFF and OPEN> is displayed for 5 seconds and  
operation returns to the main run screen. If there is a second Q-RPT with SDS, its SDS  
is CLOSED.  
2. If the active RPT IS SDS EQUIPPED and SDS on the active RPT is OPEN:  
SDS is CLOSED and operation returns to the main run screen.  
3. If the active RPT IS SDS EQUIPPED and SDS on the active RPT is CLOSED:  
The OPEN SDS routine is presented. The display is :  
1. Maximum acceptable pressure of active Q-RPT (always  
absolute on an Axxx Q-RPT and gauge on a Gxxx Q-RPT).  
Pmax! 350 kPa a Hi  
2. Position designator of Q-RPT for which SDS will be  
opened.  
Open SDS? 1no 2yes  
Check that the pressure applied to the TEST(+) port does NOT exceed the maximum  
acceptable value for the Q-RPT. Select <1no> to return to the main run screen without  
OPENING SDS, select <2yes> to OPEN SDS and return to the main run screen with  
SDS OPEN (the active Q-RPT open to the TEST(+) port).  
Opening SDS with a pressure greater than Pmax! applied to the test port may cause  
overpressure damage to the Q-RPT.  
In differential and parallel measurement modes, opening SDS acts simultaneously on  
BOTH THE Hi AND Lo Q-RPTs (see Section 3.3.8.1). The Pmax! pressure is the Lo RPT.  
Be sure to check BOTH Q-RPT TEST(+) ports are at a safe pressure before opening SDS.  
The [SDS] key is also the [2] key which is pressed to select <2Yes> to OPEN SDS.  
Thus, SDS can be OPENED by two rapid presses of [SDS]. Use this feature to  
conveniently OPEN SDS but always check that the pressure connected the TEST(+) port  
does NOT exceed Pmax! before doing so.  
When changing ranges causes a change of active Q-RPT, SDS is automatically CLOSED for  
the Q-RPT that is being changed from, leaving the inactive Q-RPT with SDS CLOSED.  
The Lo and Hi Q-RPTs’ SDS, if present, can be controlled directly regardless of which  
Q-RPT is currently active (see Section 3.5.4).  
SDS can be permanently opened so operation is as if SDS were not present  
(see Section 3.5.4.2).  
Page 45  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
3.3.8.1  
SDS IN DIFFERENTIAL AND PARALLEL MEASUREMENT  
MODES  
In differential and parallel measurement modes, opening SDS opens SDS for  
BOTH the Hi and Lo Q-RPTs. Before opening SDS, be certain that the  
pressure applied to both the Hi and Lo RPM4 TEST(+) ports is less than the  
maximum pressure of the Lo Q-RPT.  
Differential (see Section 3.3.3.1) and parallel measurement modes (see Section  
3.5.7.3) use two Q-RPTs in one RPM4 to simultaneously. In these modes,  
function of the [SDS] key is adapted to facilitate operation using both Q-RPTs  
simultaneously. [SDS] can be used to OPEN SDS on both the active an inactive  
Q-RPTs at the same time.  
Pressing [SDS] always CLOSES any ON and OPEN SDS, as it does in single Q-RPT  
mode operation. However, if SDS is CLOSED for any and all modules equipped  
with SDS, pressing SDS goes to the usual OPEN SDS routine which will OPEN  
SDS for both Q-RPTs.  
The display is :  
1. Maximum acceptable pressure of the Lo  
Q-RPT (always absolute on an Axxx Q-RPT  
and gauge on a Gxxx Q-RPT).  
Pmax! 350 kPa a HL  
2. Position designator of active Q-RPT. <HL> in  
Open Hi&Lo? 1no 2yes  
parallel mode, <Hd> in differential mode.  
Check that the pressure applied to BOTH the TEST(+) ports does NOT exceed  
the maximum acceptable value for the Lo Q-RPT. Select <1no> to return to the  
main run screen without OPENING SDS, select <2yes> to OPEN SDS for both  
Q-RPTs and return to the main run screen with SDS OPEN (the active Q-RPT  
open to the TEST(+) port).  
3.3.9  
[AUTOZ]  
 PURPOSE  
To run the AutoZ function that rezeros the active Q-RPT between full calibrations.  
See Section 3.5.1,  Principle for a full explanation of the AutoZ function.  
 PRINCIPLE  
Run AutoZ is the function by which the current Q-RPT reading is compared to a reference,  
Pstd,0, at atmospheric pressure to determine a new value of Poffset. The value of Poffset is then  
used by AutoZ to automatically correct the Q-RPT for possible changes in zero over time  
(see Section 3.5.1,  PRINCIPLE).  
Running AutoZ in parallel mode (see Section 3.5.7.3) autozeros the Hi and Lo Q-RPTs  
simultaneously and independently. There is are no Zoffset values specific to the HL Q-  
RPT.  
See Section 3.3.9 to run AutoZ.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 46  
3. OPERATION  
3.3.9.1  
[AUTOZ] IN GAUGE AND NEGATIVE GAUGE MODE  
 PURPOSE  
To “rezero” the active Q-RPT in gauge measurement mode.  
See Section 3.5.1,  Principle for a full explanation of the AutoZ function.  
 OPERATION  
For the AutoZ function key to run AutoZ, AutoZ must be turned ON for the  
active range and measurement mode. AutoZ ON is indicated by <z> to the  
left of the Q-RPT designator on the first line of the main run screen. AutoZ  
ON and OFF is set using [SPECIAL], <1AutoZ> (see Section 3.5.1). If AutoZ  
is OFF for the active Q-RPT, and measurement mode, <AutoZ is off >  
is displayed when [AutoZ] is pressed.  
Running AutoZ in or parallel mode (see Section 3.5.7.3) autozeros both the  
Hi and Lo Q-RPTs simultaneously.  
To run AutoZ in gauge measurement mode, set gauge or negative gauge as the  
measurement mode (see Section 3.3.3) and press [AutoZ] from the main run  
screen. If the Q-RPT is a Gxxx or BGxxx type, the display is <Preparing to  
AutoZ> for five seconds to allow time for the bypass valve between the TEST(+)  
and TEST(-) sides of the Q-RPT to assure zero differential pressure and for the  
pressure to stabilize (see Section 5.6, Figure 8). <Running gauge AutoZ> is  
displayed briefly before returning to the main run screen.  
Before running AutoZ in gauge mode, ensure that the pressure applied to  
the Q-RPT is truly zero gauge (atmospheric pressure). If running AutoZ in  
gauge mode results in a zero offset that RPM4 considers unusually large,  
<Confirm 0 gauge P!> is displayed when AutoZ is pressed. Check that zero  
gauge pressure is applied to the TEST(+) port and there is no differential  
pressure across the TEST(+) and TEST(-) ports and press ENTER to  
continue or ESCAPE to abort.  
Allow the RPM4 to stabilize at atmospheric pressure and ambient  
temperature for 1 to 2 minutes before running AutoZ in gauge mode.  
Page 47  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
3.3.9.2  
[AUTOZ] IN ABSOLUTE MODE  
 PURPOSE  
To “rezero” the active Q-RPT in absolute measurement mode  
See Section 3.5.1,  Principle for a full explanation of the AutoZ function.  
 OPERATION  
For the AutoZ function key to run AutoZ, AutoZ must be turned ON for the  
active Q-RPT and measurement mode. AutoZ ON is indicated by <z> to the  
left of the range designator on the first line of the main run screen. AutoZ  
ON and OFF is set using [SPECIAL], <1AutoZ> (see Section 3.5.1). If AutoZ  
is OFF for the active range, and measurement mode, <AutoZ OFF> is  
displayed when [AutoZ] is pressed.  
Running AutoZ in or parallel mode (see Section 3.5.7.3) autozeros both the  
Hi and Lo Q-RPTs simultaneously.  
To run AutoZ in absolute measurement mode, set absolute measurement mode  
(see Section 3.3.3) and press [AutoZ] from the main run screen. The display is:  
1. Active Q-RPT designator.  
AutoZ Hi abs by:  
2. Current measurement mode (absolute).  
1Entry 2COM2 3Lo RPT  
3. Selection of source of Pstd,0 reference to which  
to AutoZ.  
Selecting <1Entry> allows the value of Pstd,0 to be entered from the front panel keypad.  
Selecting <2COM2> allows the value of Pstd,0 to be read automatically from another  
DHI RPMx connected to RPM4’s COM2 communications port.  
Selecting <3Lo RPT> is shown only if the active Q-RPT is Hi and there is a Lo  
Axxx Q-RPT in the RPM4. This selection allows the value of Pstd,0 for the Hi  
Q-RPT to be read automatically from the RPM4s Lo Q-RPT.  
Allow the RPM4 to stabilize at atmospheric pressure and ambient  
temperature for 10 to 15 minutes before running AutoZ in absolute mode.  
If running AutoZ results in a value of Poffset that is greater than ± 0.005 % FS of  
the span of the Q-RPT that is being AutoZeroed, the Q-RPT and/or the reference  
used as the source of Pstd,0 may be out of tolerance or the AutoZ process may  
have been faulty. Before activating a new Poffset greater than ± 0.005 % FS of  
the active Q-RPT, check to be sure that both the Q-RPT and the reference  
were in good working order, properly vented to stable atmospheric pressure,  
at the same height, and reading in the same pressure units when AutoZ was run.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 48  
3. OPERATION  
When the run AutoZ selection is made, if a HEAD correction is currently active  
(see Section 3.3.7) the head correction is momentarily disabled while running  
AutoZ to avoid “zeroing out” the head value.  
The value of Poffset is always displayed and entered in Pascal (Pa).  
Run AutoZ by Entry  
AutoZ by entry allows the value of Pstd,0 (see Section 3.5.1,  PRINCIPLE) to be  
entered directly from the RPM4 front panel. This provides a simple way of  
AutoZeroing relative to an independent reference device such as a house  
barometer that does not interface directly with RPM4.  
To access run AutoZ by entry press [AutoZ], <1entry>. The display is:  
1. Real time pressure reading (without head  
correction), pressure unit of measure and  
measurement mode of the active Q-RPT.  
96.7755 kPa a  
Pstd,0:0.00000  
Hi  
2. Active Q-RPT position designator.  
3. Entry field for the value of Pstd,0. in the current  
pressure unit of measure.  
Enter the value of the AutoZ reference (Pstd,0) in the same unit of measure as the  
top line display and press [ENT]. RPM4 logs the reading and calculates a new  
AutoZ offset value. The next display is:  
Press [ENT] to activate the new value of  
Poffset or [ESC] to start over with entry of a  
new AutoZ reference (Pstd,0) value.  
Old Poffset: 0.0 Pa  
New Poffset: 8.3 Pa  
The value of Poffset is always in Pascal (Pa). The value of Pstd,0 is entered in  
the current pressure unit of measure.  
Run AutoZ by COM2  
AutoZ by COM2 allows the value of Pstd,0 (see Section 3.5.1  Principle) to be read  
automatically from a DHI RPMx connected to the RPM4 COM2 communications  
port. The RPMx is read and the new Poffset is calculated automatically.  
Page 49  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
To access run AutoZ by COM2 press [AutoZ], <2COM2>. The display is:  
1. Real time pressure reading (without head  
correction), pressure unit of measure and  
measurement mode of the active Q-RPT.  
96.7755 kPa a  
Pstd,0:0.00000  
Hi  
2. Active Q-RPT position designator.  
3. Real time reading from the RPMx connected  
to RPM4’s COM2 communications port.  
Observe the displayed pressures and verify that they are stable. When ready,  
press [ENT] to cause AutoZ to run. RPM4 logs both readings and calculates a  
new AutoZ offset value. The display is:  
Old Poffset: 0.0 Pa  
New Poffset: 3.1 Pa  
Press [ENT] to activate the new value of  
Poffset or [ESC] to start over.  
For RPM4 to communicate with an RPMx connected to its COM2 port, the  
RPM4 and the RPMx RS-232 interfaces must be set up properly  
(see Section 3.5.2). If, the RPM4 is unable to communicate with an RPMx via  
COM2 when running AutoZ by COM2, it times out after 6 seconds and  
displays <RPM NOT detected>.  
The value of Poffset is always displayed and entered in Pascal (Pa).  
Run AutoZ by Lo RPT  
AutoZ by Lo RPT is available only if the active Q-RPT is the Hi Q-RPT and there  
is an Axxx Lo Q-RPT. AutoZ by Lo RPT allows the Lo Q-RPT in an RPM4 to serve  
as the AutoZ reference (source of Pstd,0) (see Section 3.5.1,  PRINCIPLE).  
The Lo Q-RPT is read and the new Poffset is calculated automatically.  
To access run AutoZ by Lo RPT press [AutoZ], <3Lo RPT>. The display is:  
1. Real time pressure reading (without head  
correction), pressure unit of measure and  
96.7755 kPa a  
Pstd,0:97.7786  
Hi  
measurement mode of the active Q-RPT.  
2. Active Q-RPT position designator.  
3. Real time reading from the Lo Q-RPT.  
Observe the displayed pressures and verify that they are stable. When ready,  
press [ENT] to cause AutoZ to run. RPM4 logs both readings and calculates a  
new AutoZ offset value. The display is:  
Old Poffset: 0.0 Pa  
New Poffset: 3.1 Pa  
Press [ENT] to activate the new value of  
Poffset or [ESC] to start over.  
The value of Poffset is always displayed and entered in Pascal (Pa).  
© 2004-2007 DH Instruments, a Fluke Company  
Page 50  
3. OPERATION  
3.3.9.3  
AUTOZ IN DIFFERENTIAL MODE  
 PURPOSE  
To compensate for the offset between the Hi Q-RPT and the Lo Q-RPT at the  
operating “line pressure” in differential measurement mode.  
See Section 3.5.1,  Principle for a full explanation of the AutoZ function.  

OPERATION  
For the AutoZ function key to run AutoZ, AutoZ must be turned ON for the  
active range and measurement mode. AutoZ ON is indicated by <z> to the  
left of the Q-RPT designator on the first line of the main run screen. AutoZ  
ON and OFF is set using [SPECIAL], <1AutoZ> (see Section 3.5.1). If AutoZ  
is OFF for the active Q-RPT, and measurement mode, <AutoZ is off > is  
displayed when [AutoZ] is pressed.  
To run AutoZ in differential measurement mode, set differential as the  
measurement mode (see Section 3.3.3) and press [AutoZ] from the main run  
screen. <Running differential AutoZ> is displayed briefly before returning to the  
main run screen.  
Before running AutoZ in differential mode, set the “line pressure” at which  
the differential measurements will be made and assure that a common  
pressure is applied to both Q-RPTs. If running AutoZ in differential mode  
results in a zero offset that RPM4 considers unusually large, <Confirm 0  
DP> is displayed when AutoZ is pressed. Check that zero differential  
pressure is applied across the Hi and Lo TEST(+) ports and press ENTER to  
continue or ESCAPE to abort.  
Allow the RPM4 to stabilize at atmospheric pressure and ambient  
temperature for 2 to 3 minutes before running AutoZ in differential mode.  
3.3.10 [ENT] (RUN AUTOTEST)  
 PURPOSE  
To run the AutoTest function which AutoRanges the RPM4 and runs a calibration test based  
on user entries of pressure unit, measurement mode, full scale, increment and DUT  
tolerance.  
Run AutoTest is accessed by pressing [ENT] from the Rate or Clean DISPLAY mode (see  
Section 3.3.6.2). In other DISPLAY modes, the function of [ENT] is specific to the mode.  
Page 51  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
 PRINCIPLE  
This feature not available at the time of release of this manual. Check www.dhinstruments.com  
for new RPM4 embedded software releases and manual updates.  
 OPERATION  
Feature not available at the time of release of this manual.  
3.4  
[SETUP]  
 PURPOSE  
[SETUP] accesses a menu of functions and features commonly used in setting up and using RPM4.  
 OPERATION  
1range 2res 3stab  
4UL 5ATest  
To access the SETUP menu, press [SETUP] from the MAIN RUN  
screen. The display is:  
SETUP menu choices include:  
<1range>  
<2res>  
Save and delete ranges created by AutoRange (see Section 3.4.1).  
Adjust the resolution of pressure displays (see Section 3.4.2).  
<3stab>  
Adjust the pressure stability test that is the criterion for the Ready/Not Ready indication  
(see Section 3.3.3).  
<4UL>  
Adjust upper and lower pressure limit alarms (see Section 3.4.4).  
<5ATest>  
View data files resulting from running QDUT AutoTests (See Section 3.4.5).  
3.4.1  
<1RANGE>  
 PURPOSE  
Save AutoRange ranges and associated settings for recall. Delete previously saved AutoRange ranges.  
 PRINCIPLE  
The RPM4 AutoRange function creates a range and automatically sets various operating  
parameters proportionally to the range (see Section 3.3.4). Operating settings can then be  
changed by the user. Many operating settings are specific to the current range (see Table 4).  
[SPECIAL], <1range> allows the AutoRange range and associated settings to be saved for  
recall using the [RANGE] key (see Section 3.3.1). This can avoid having to recreate  
frequently used ranges and settings.  
[SPECIAL], <1range> is also used to delete ranges that have been saved but are no longer needed.  
3.4.1.1  
SAVING AN AUTORANGE RANGE  

OPERATION  
To save a range created by AutoRange, the range must be the active range.  
Use AutoRange to create the range (see Section 3.3.4) and then make any  
desired feature and setting adjustments.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 52  
3. OPERATION  
Once the AutoRange range is set up as desired, press [SETUP], <1range>,  
<1save>. The display is:  
1. Indication that this is a range to be saved.  
2. Designator and position of the Q-RPT used by  
the range to be saved.  
Save range A700K Hi  
3. Pressure unit of measure of the range to be  
kPa 300g/100a  
saved.  
4. Full scale pressure of the range to be saved in  
gauge mode and absolute mode if available.  
Press [ENT] to save the range or [ESC] to return to the MAIN RUN screen without  
saving the range.  
Default (<DF>) Q-RPT ranges cannot be saved. They are permanent.  
Duplicate AutoRange ranges cannot be saved. A duplicate AutoRange range  
is a range that has the same measurement mode and full scale and uses the  
same Q-RPT as a range that has already been saved.  
3.4.1.2  
DELETING AUTORANGE RANGES  

OPERATION  
To delete a single saved AutoRange range, press [SETUP], <1range>, <2delete>.  
If there are any saved ranges available to delete, the display is:  
1. Indication that the cursor control keys may be  
used to toggle through the saved ranges to  
select the one to be deleted.  
2. Designator and position of the Q-RPT used by  
< and > A700K Hi  
the range to be deleted.  
kPa 300g/100a  
3. Pressure unit of measure of the range to be  
deleted.  
4. Full scale pressure of the range to be deleted  
in gauge mode and absolute mode if available.  
Use the cursor control keys to toggle through the ranges available to be deleted.  
When the desired range to be deleted is displayed, press [ENT]. If you are sure you  
want to delete this range, press [ENT] again in response to the <Delete?> query.  
[ESC] returns to the <AutoRange:> screen without deleting a range.  
To delete all of the saved AutoRange ranges, press [SETUP], <1range>,  
<3delete all>. If you are sure you want to delete all the ranges, respond <1yes>  
to the <Delete all saved ranges?> query. If not, respond <2no>.  
3.4.2  
<2RES> (RESOLUTION)  
 PURPOSE  
To set the resolution with which measured pressures and other pressure indications and  
settings are displayed.  
 PRINCIPLE  
The resolution with which RPM4 displays pressure values can be adjusted. This feature can  
be used to reduce the resolution when lower precision measurements are being made and  
excess resolution might confuse or distract the operator.  
The resolution setting determines the number of digits with which pressure is displayed.  
The resolution is calculated based on the span of the range and then rounded to the furthest  
Page 53  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
digit to the right. For example, resolution of 0.001 % on a range of 150 kPa is  
150 X 0.001 % = 0.0015 which is rounded down to 0.001 kPa.  
Default resolution is 10 ppm of active range span. Resolution is set automatically by  
AutoRange (see Section 3.3.4).  
 OPERATION  
Display resltn: Hi  
0.0010 %FS < and >  
To access the resolution function, press [SETUP],  
<2res>. The display is:  
Use the cursor control keys to set the desired level of resolution. Press [ENT] to return to the  
MAIN RUN screen with the new resolution setting active or [ESC] to make no changes.  
The resolution setting is range specific. A resolution setting made in one range does NOT  
affect other ranges.  
The measured pressure resolution is fixed for altitude units at 1 m in meters and 1 ft in feet.  
The maximum resolution setting is limited in AutoRange ranges that are less than 10% of the  
Q-RPT default full scale.  
3.4.3  
<3STAB>  
 PURPOSE  
To view and/or adjust the stability test that is the Ready/Not Ready criterion for the active  
RPT and range.  
See Section 3.2.1 Pressure Ready/Not Ready Indication.  
 PRINCIPLE  
RPM4 continuously monitors the rate of change of pressure measured by the active RPT and  
range and compares this rate to the stability limit to make a Ready/Not Ready determination  
(see Section 3.2.1 Pressure Ready/Not Ready Indication). The stability function allows the  
stability limit to be adjusted by the user to increase or decrease the stability required for a  
Ready condition to occur.  
The default stability limit is + 0.005% FS of the active range.  
The stability limit is separate and different from the Rate DISPLAY function (see Section  
3.3.6.2) which allows the current rate of change of pressure to be displayed.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 54  
3. OPERATION  
 OPERATION  
Stability:  
0.020 Pa  
Hi  
To access the stability setting adjustment, press  
[SETUP], <3stab>. The display is:  
Edit the desired stability limit setting if desired. [ENT] activates the stability limit for the active  
range and returns to the main run screen Press [ESC] to return to the MAIN RUN screen  
with no change to the stability limit.  
The stability setting is range specific. A stability setting made in one range does NOT  
affect other ranges.  
3.4.4  
<4UL> (UPPER LIMIT)  
 PURPOSE  
To set the upper and lower pressure limit values for a pressure range and measurement mode.  
 PRINCIPLE  
The UPPER LIMIT function provides the user with settable pressure limits at which an alarm  
sounds. Absolute and gauge measurement modes (see Section 3.3.3,  PRINCIPLE) have  
upper limits only. Negative gauge mode and the BA100K also have a lower limit.  
When the limit is reached, RPM4’s beeper sounds intermittently as long as pressure is  
outside the limit.  
The UPPER LIMIT function has two purposes. First, when UL is set to its default value, it serves  
as a warning that the maximum pressure of the active range (and lower pressure in negative  
gauge mode) is about to be exceeded. Second, UL can be set by the user to a value other  
than the default value to provide an alarm that a specific pressure limit has been exceeded.  
This feature is often used to help protect an external device or system on which RPM4 is  
being used to measure pressure. For example, it might be set just over the full scale of a  
device under test (DUT) that is being calibrated. Note that using AutoRange automatically  
sets the UL to just above the AutoRange full scale (see Section 3.3.4).  
The default upper limit is 105 % of AutoRange span or 102 % of Q-RPT default (maximum)  
range, whichever is lower. The default lower limit (negative gauge mode only ) is – 110 kPa  
(- 16 psi), except with the BG15K Q-RPT in which the default lower limit is the negative  
equivalent of the upper limit. The default lower limit of the BA100K Q-RPT is 66 kPa (9.6 psi).  
In parallel measurement mode (see Section 3.5.7.2), the default and maximum UL is the  
UL of the Lo Q-RPT.  
In differential measurement mode (see Section 3.3.3.1), UL has upper and lower limits.  
The default upper differential UL is the maximum pressure of the Hi Q-RTP. The default lower  
UL is the negative value of the upper limit.  
In differential measurement mode, the ULs on the Lo Q-RPT and Hi Q-RPT default range are  
also active so that line pressure (Lo Q-RPT) and total pressure (Hi Q-RPT) upper limit can be  
set and monitored in addition to a differential limit.  
Page 55  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
 OPERATION  
To view or edit upper and lower limits press [SETUP], <4UL>.  
If the current measurement mode is absolute or gauge, there is an upper limit only.  
The display is:  
Upper limit:  
204.000 kPa a  
Hi  
1. Entry field for upper limit value in active pressure unit of  
measure and measurement mode.  
Edit the upper limit value as desired. The maximum upper limit is 105 % of span in an  
AutoRange range or 102 % of default Q-RPT full scale, whichever is smaller. Press [ENT] to  
return to the MAIN RUN screen with the new upper limit active. Press [ESC] to return to the  
MAIN RUN screen with no change to the upper limit.  
If the current measurement mode is negative gauge, there is an upper limit and a lower limit.  
The display is:  
1. Entry field for upper limit value.  
Upper: 104.00  
Hi  
2. Entry field for lower limit value and active range pressure unit  
of measure and measurement mode indication.  
Lower:-110.00 kPa g  
Edit the upper and lower limit values as desired. Use the cursor control keys to move  
between the two edit fields. The lower limit must be a negative value. Press [ENT] to return  
to the MAIN RUN screen with the new upper and/or lower limit active. Press [ESC] to return  
to the MAIN RUN screen with no change to the limits.  
When the upper or lower limit has been exceeded, the display of current pressure flashes  
and a buzzer sounds for 3 seconds on/2 seconds off intervals. Change the pressure applied  
to RPM4 so that it is within the upper and/or lower limit to return to normal operation.  
Upper limit values are specific to each range and measurement mode. Be careful not to  
assume that the upper limit set in one measurement mode will apply to the other.  
For example, if you change the upper limit in gauge mode, the upper limit will not be  
changed in negative gauge mode.  
Upper limits are always specified and displayed in the current pressure unit except for  
altitude units. When in altitude units, upper limits are expressed in kPa if the altitude  
unit is meters (m) and psi if the altitude unit is feet (ft).  
In Hi Q-PRT differential mode (see Section 3.3.3.1) there are two UL values for the Hi Q-  
RPT. One is the upper and lower limts for differential pressure, with a default value equal  
to the span of the Lo RPT. The other is the UL on the base mode of the Hi Q-RPT DF  
range to monitor the maximum pressure on the Hi Q-RPT. In differential mode, the Lo Q-  
RPT UL is also active to provide monitoring of the differential mode line pressure.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 56  
3. OPERATION  
3.4.4.1  
OVER PRESSURE FUNCTION  
In addition to the UL function, RPM4 has an over pressure function.  
The over pressure function executes when a Q-RPT measures a pressure that is  
104 % of its default span. The G15K and BG15K Q-RPTs also have a negative  
over pressure function. The negative over pressure function executes when the  
Q-RPT measures a pressure less than - 17.5 kPa (- 2.3 psi).  
The over pressure function causes the measured pressure display to flash.  
If the Q-RPT module is equipped with SDS, SDS closes shutting off the TEST(-)  
port (see Section 3.2.7). If the Q-RPT is a Gxxx or BGxxx, the TEST(+)/TEST(-)  
bypass valve is opened (see Section 5.6, Figure 8). The overpressure function also  
logs the time and date of the overpressure condition in both user and factory logs to  
assist in incident diagnosis (see Section 3.5.7.5).  
To recover from an overpressure condition, cycle RPM4 power. Be sure to  
correct the condition that caused the overpressure before cycling power.  
3.4.5  
<5ATEST>  
This feature not available at the time of this manual’s release. Check www.dhinstruments.com  
for new RPM4 embedded software releases and manual updates.  
3.5  
[SPECIAL]  
 PURPOSE  
[SPECIAL] accesses a menu of RPM4 functions and features that are less commonly used or not  
normally used in regular operation.  
 OPERATION  
1AutoZ 2remote 3head  
Press [SPECIAL] from the MAIN RUN screen to access the  
SPECIAL menu. The display is:  
4SDS 5prefs 6Punit  
7intern 8cal 9reset  
Some screens, such as the SPECIAL menu, go beyond the two lines provided by the display. This is  
indicated by a flashing arrow in the second line of the display. Press the cursor control keys to move the  
cursor to access the lines that are not visible or directly enter the number of the hidden menu choice if you  
know it.  
SPECIAL menu choices include:  
<1AutoZ>  
<2remote>  
Manage AutoZero function for the active Q-RPT (see Section 3.5.1).  
View and edit COM port (RS-232) and IEEE-488 interface settings. Select remote syntax  
style (see Section 3.5.2).  
<3head>  
<4SDS>  
<5prefs>  
Set HEAD function fluid and height unit of measure (see Section 3.5.3).  
To view and set the ON/OFF and OPEN/CLOSED status of SDS for all Q-RPTs.  
View and set screen saver time, keypad sound frequency, unit ID number, time/date,  
security protection level (see Section 3.5.5).  
<6Punit>  
<7intern>  
Customize the [UNIT] key pressure unit of measure selections (See section 3.5.6).  
Access internal functions including on-board barometer viewing, read rate adjustment, parallel  
measurement mode ON/OFF, direct control of Lo Vent valve(s), incident log viewing (see  
Section 3.5.7).  
<8cal>  
View and adjust RPM4, Q-RPT and barometer calibration coefficients (see Sections 3.5.8, 5.2, 5.3).  
Access RPM4’s various reset functions (see Section 3.5.9).  
<9reset>  
Page 57  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
3.5.1  
<1AUTOZ>  
 PURPOSE  
To offset the RPM4 Q-RPT(s) readings relative to a reference value in order to compensate  
for possible changes in Q-RPT zero between full recalibrations. In differential measurement  
mode, to compensate for the difference between the reading of the Hi and Lo Q-RPTs at the  
“line pressure” at which differential measurements are made.  
To assure operation within measurement uncertainty specifications (see Section 1.2.2), it is  
recommended that AutoZ be run (the value of Poffset updated) whenever vented in gauge mode,  
whenever the line pressure is changed in differential mode and at least every 30 days or when  
RPM4 has been exposed to temperature changes exceeding 15 ºC (36 ºF) in absolute mode.  
 PRINCIPLE  
AutoZ Purpose and Principle  
The main component of the change over time of the RPM4 Q-RPTs is change in zero or  
offset, independent of span. Offsetting or “rezeroing” RPM4 Q-RPTs relative to a reference  
between recalibrations allows measurement uncertainty specifications to be maintained with  
less frequent full calibrations. AutoZ is also used to compensate for the difference between  
the Hi and Lo Q-RPT at the “line pressure” at which differential measurements are made.  
The RPM4 AutoZero function (AutoZ) provides full on-board support for the rezeroing  
process to simplify its application by the user.  
The AutoZero function uses three values:  
1. Pstd,0  
:
The pressure value indicated by the AutoZ reference, the device that is acting as  
the reference relative to which to offset the RPM4 Q-RPT.  
For Axxx (absolute) Q-RPTs in absolute measurement mode, the pressure at which  
AutoZ is performed is normally atmospheric pressure and the Pstd,0 value can be supplied  
a) by manual entry, b) automatically from a DHI RPMx connected to RPM4 COM2  
communications port, or c) automatically from an Axxx Lo Q-RPT if one is present in the  
RPM4.  
For Gxxx or BGxxx (gauge) Q-RPTs or Axxx (absolute) Q-RPTs in gauge measurement  
mode, Pstd,0 is always zero (atmospheric pressure) which is supplied by definition when  
the Q-RPT is vented to atmosphere.  
For RPM4s with two Q-RPTs of the same type (Axxx, Gxxx, BGxxx) with the Hi Q-RPT in  
differential measurement mode, Pstd,0 is the pressure indicated by the Lo Q-RPT when  
the Hi and Lo Q-RPTs are connected to a common pressure.  
2. Pu,0:  
The pressure reading of the Q-RPT, with no AutoZ offset, at the time AutoZ is  
performed.  
3. Poffset,G , Poffset,A and Poffset,D: The difference between the reading of the Q-RPT with no  
AutoZ offset (Pu,0) and the indication of the AutoZ reference (Pstd,0) for gauge (G),  
absolute(A) or differential (D) measurement mode:  
Poffset = Pu,0 - Pstd,0  
Poffset represents the difference between the Q-RPT reading (Pu,0) and the AutoZ standard  
(Pstd,0). The AutoZ function manages the determination, storage and application of Poffset to  
correct the zero offset in absolute, gauge and differential measurement modes.  
When the Q-RPT is calibrated, Poffset is set to zero. Poffset is then redetermined at regular  
intervals using the AutoZ function. The most recent value of Poffset is applied to the Q-RPT  
reading to correct for change in zero.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 58  
3. OPERATION  
The AutoZ function can be turned ON and OFF. Table 7 summarizes the effect of AutoZ ON  
and OFF for the three Q-RPT types in different measurement modes.  
AutoZ in absolute measurement mode with an Axxx Q-RPT  
Q-RPTs with the designation Axxx are intrinsically absolute. They have an evacuated and  
sealed reference. Axxx Q-RPTs can measure absolute pressure (difference from vacuum).  
In absolute measurement mode, the source of Pstd,0 must be an absolute pressure, nominally  
atmospheric pressure, with uncertainty significantly better than that of the Q-RPT that is  
being AutoZeroed. For higher range Q-RPTs, this is easily accomplished with a variety of  
digital barometers or with a Lo Q-RPT in the RPM4. For lower range Q-RPTs, a piston gauge or  
other standard may be required to provide Pstd,0 with low enough uncertainty.  
When using an Axxx (absolute) Q-RPT in absolute measurement mode, with AutoZ ON,  
absolute pressure is calculated as:  
Pabs = Pu - Poffset,A  
In absolute measurement mode, running the AutoZ function to update the AutoZ value  
(Poffset,A), is initiated by the operator using [AutoZ].  
AutoZ in gauge and negative gauge measurement modes with an Axxx Q-RPT,  
dynamic compensation for atmospheric pressure  
Q-RPTs with the designation Axxx are intrinsically absolute but they are also used in gauge  
and negative gauge measurement modes (difference from atmosphere) (see Section 3.3.3,  
 PRINCIPLE). Gauge measurement mode is achieved by subtracting the value of  
atmospheric pressure from the Q-RPT’s absolute reading using AutoZ and by dynamically  
compensating for changes in atmospheric pressure between opportunities for AutoZ to  
execute (see Section 3.2.2).  
In gauge measurement modes on an Axxx Q-RPT, the value of Pstd,0 is always zero gauge  
pressure. Zero gauge pressure, by definition, is applied to the Q-RPT when it is vented to  
atmosphere. In gauge measurement modes, AutoZ is run when initiated by the operator  
pressing [AutoZ] when the RPM4 is vented. This assures regular updating of the Poffset,G  
value corresponding to atmospheric pressure. Gauge pressure is the measured absolute  
pressure, Pu, minus Poffset,G  
.
Pgauge = Pu - Poffset,G  
When AutoZ is ON, dynamic compensation for atmospheric pressure is also applied to  
compensate for changes in atmospheric pressure as measured by a barometer (ΔPatm) between  
AutoZ updates (see Section 3.2.2). The measured gauge pressure is calculated using ΔPatm  
to correct the value of Poffset.G  
.
Pgauge = Pu - Poffset.G - ΔPatm  
In gauge measurement mode on an Axxx RPT, running the AutoZ function to update the  
value of Patm,0, is initiated by the operator using [AutoZ]. Updating of ΔPatm occurs  
automatically and continuously.  
When gauge or negative gauge mode is first activated on an Axxx Q-RPT, the value of  
Poffset.G subtracted from the absolute pressure reading to achieve gauge pressure is  
standard atmosphere of 101.325 kPa. This can cause a large zero error when gauge mode  
is activated if atmospheric pressure is significantly different from standard atmospheric  
pressure. When gauge mode is activated, always press [AutoZ] to run AutoZ and obtain  
an actual value of Poffset.G  
.
Page 59  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
AutoZ in gauge measurement mode with a Gxxx or BGxxx Q-RPT  
Q-RPTs with the designation Gxxx or BGxxx are intrinsically gauge. They have an atmospheric  
(TEST(-)) reference port and measure gauge pressure (difference from atmosphere).  
In gauge measurement mode the value of Pstd,0 is always zero gauge pressure. Zero gauge  
pressure, by definition, is applied to the Q-RPT when it is vented to atmosphere.  
When using a Gxxx Q-RPT in gauge measurement mode, with AutoZ ON, gauge pressure is  
calculated as:  
Pgauge = Pu - Poffset,G  
In gauge measurement modes, AutoZ is run when initiated by the operator pressing [AutoZ]  
when the RPM4 is vented. This assures the regular automated updating of the Poffset,G value.  
AutoZ in differential measurement mode  
RPM4s with two Q-RPTs of the same type (Axxx, Gxxx, BGxxx) support differential  
measurement mode (see Section 3.3.3.1) in which the measured pressure is the difference  
between the pressure measured by the Hi Q-RPT and the Lo Q-RPT (Hi – Lo).  
In differential measurement mode, the purpose of AutoZ is to compensate for the offset  
between the Hi and Lo Q-RPT indications at the “line pressure” at which the differential  
pressure is being measured. The value of Pstd,0 is the pressure indicated by the Lo Q-RPT at  
the time of AutoZ.  
When using an RPM4 with two Q-RPTs in differential measurement mode, with AutoZ ON,  
differential pressure is calculated as:  
Pdifferential = PHi - PLo - Poffset,D  
In differential measurement mode, AutoZ is run when initiated by the operator pressing  
[AutoZ] when both Q-RPTs of the RPM4 are connected to a common pressure..  
AutoZ ON/OFF  
The AutoZ function can be turned ON and OFF, separately for gauge, absolute and  
differential measurement modes. Table 7 summarizes the effect of AutoZ ON and OFF.  
Table 7. AutoZ ON and OFF  
AutoZ  
ROUTINE  
RUNS  
Q-RPT  
TYPE  
MEASUREMENT  
MODE  
AutoZ  
STATUS  
Poffset  
APPLIED  
ΔPatm  
APPLIED  
When initiated  
by operator  
ON  
YES  
NO  
Absolute  
Not Applicable  
OFF  
ON  
Not available  
Axxx  
YES  
NO  
When initiated  
by operator  
Gauge or  
negative gauge  
YES  
OFF  
When initiated  
by operator  
Gxxx  
or  
BGxxx  
ON  
OFF  
ON  
YES  
NO  
Gauge or  
negative gauge  
Not Applicable  
Not Applicable  
Not available  
When initiated  
by operator  
Any, Hi Q-RPT  
in dual Q-RPT  
RPM4  
YES  
NO  
Differential  
Not available  
OFF  
Recommendations for the Use of the AutoZ Function  
The AutoZ function provides a powerful and easy to use tool for improving the stability over  
time of RPM4 Q-RPTs and maximizing the recalibration interval by compensating for change  
in zero between full recalibrations. In differential measurement mode, it minimizes the  
uncertainty in the differential pressure due to the offset between the Hi and Lo Q-RPTs at the  
© 2004-2007 DH Instruments, a Fluke Company  
Page 60  
3. OPERATION  
“line pressure”. The following simple recommendations will help assure that you use this  
feature to best advantage.  
In gauge and differential measurement mode: Always leave AutoZ ON when  
operating.  
In absolute measurement mode: Always leave AutoZ ON when operating if the AutoZ  
routine has been run regularly using a valid atmospheric reference.  
To assure operation within measurement uncertainty specifications (see Section 1.2.2),  
run AutoZ whenever vented in gauge mode, whenever the line pressure is changed in  
differential mode and at least every 30 days or when RPM4 has been exposed to  
temperature changes exceeding 15 ºC (36 ºF) in absolute mode.  
In absolute measurement mode:  
Run AutoZ only when a reference whose  
measurement uncertainty is known to be significantly better than that of the Q-RPT to be  
AutoZeroed is available. Keep range ratios in mind when comparing uncertainty.  
A ± 0.01 % FS barometer is roughly 10 times better than an ± 0.01 % 1 MPa (150 psi)  
Q-RPT because the Q-RPT/barometer pressure ratio is 10:1. The measurement  
uncertainty comparison should be made at 30 % of span for both standard class and  
premium class Q-RPTs. Though it may not be practical and generally is not necessary,  
the best possible reference with which to run AutoZ in absolute measurement mode is a  
gas operated piston gauge (such as a DHI PG7601) applying atmospheric pressure to  
the RPM4 test port. The best day to day reference is a properly calibrated DHI RPM4  
with a BA100K Q-RPT interfaced directly as an external device to the RPM4 COM2 port.  
In absolute measurement modes: Allow the RPM4 to stabilize at atmospheric pressure  
and ambient temperature for 10 to 15 minutes before running AutoZ.  
 OPERATION  
The AutoZ function and values are Q-RPT AND measurement mode (gauge/negative gauge  
or absolute) specific.  
To RUN the AutoZ routine that rezeroes the Q-RPT, use [AutoZ] (see Section 3.3.9).  
To access the RPM4 AutoZ function press [SPECIAL], <1AutoZ>. The display is:  
1. Active Q-RPT designator.  
2. Indication of active measurement mode (<abs> for absolute,  
1off 2view  
3edit  
Hi  
<gage> for gauge and negative gauge, <dif> for differential).  
abs ON  
3. Indication of whether AutoZ is currently ON or OFF for this  
Q-RPT and measurement mode.  
Select <1off> (or <1on>) to change the AutoZ status for the current Q-RPT and  
measurement mode from ON to OFF or vice versa.  
AutoZ ON is indicated by a <z> in the MAIN RUN screen, top line, fourth character from  
the right. When AutoZ is OFF, the character is blank.  
Select <2view> to view the current value of Poffset for the active Q-RPT and measurement mode.  
Poffset should be zero when the RPM4 is new or has just been calibrated. Poffset should be  
roughly equal to atmospheric pressure for an Axxx (absolute) Q-RPT operating in gauge mode.  
Page 61  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
Select <3edit> to edit the value of Poffset for the active Q-RPT and measurement mode  
(see Section 3.5.1.1).  
The value of Poffset is always displayed and entered in Pascal (Pa).  
3.5.1.1  
EDIT AUTOZ  
The edit AutoZ function should be used with great caution as entering  
inappropriate values and turning ON AutoZ may result in out of tolerance  
measurements. In normal operation, the value of the AutoZ offset, Poffset  
,
should be changed by running AutoZ using [AutoZ] (seen Section 3.3.9).  
Before editing Poffset, see Section 3.5.1,  PRINCIPLE.  
To edit the current Poffset value for the active Q-RPT and measurement mode,  
press [SPECIAL], <1AutoZ>, <3edit>. The display is:  
1. Indication of active measurement mode  
(<abs> for absolute, <gage> for gauge and  
Poffset, Abs  
8.4 Pa  
Hi  
negative gauge, <dif> for differential).  
2. Active Q-RPT for which Poffset is being viewed.  
3. Edit field for value of Poffset  
.
Edit Poffset as desired and press [ENT] to activate the new value. Press [ESC] to  
abandon changes.  
The value of Poffset is always displayed and entered in Pascal (Pa).  
3.5.2  
<2REMOTE>  
 PURPOSE  
To configure the RPM4 COM1, COM2 and IEEE-488 (GPIB) communication ports. To test COM1  
and COM2 communications. To select the remote programming communications format.  
 PRINCIPLE  
The RPM4 has two RS-232 communications ports referred to as COM1 and COM2 and a  
single IEEE-488 (GPIB) port. COM1 or the IEEE-488 port is for communicating with a host  
computer (see Section 4), and COM2 is reserved for communicating with an external device  
(e.g. an RPMx, a multimeter, etc.). These ports’ settings can be viewed and changed using  
[SPECIAL], <2remote>.  
RPM4 has two remote communications formats, classic and ENHANCED (see Section 4.3).  
Which of these is active can be selected.  
A self test is supplied for RS-232 communications. The self test allows verification that the  
RPM4 RS232 ports (COM1 and COM2) are operating properly and that a valid interface  
cable is being used.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 62  
3. OPERATION  
 OPERATION  
To access the communications settings, press [SPECIAL], <2Remote>.  
Select <1COM1> to view and edit COM1 settings (see Section 3.5.2.1.).  
Select <2COM2> to view and edit COM2 settings (see Section 3.5.2.1.).  
Select <3IEEE> to view and edit IEEE-488 settings (see Section 3.5.2.2).  
Select <4format> to select the remote communications command format (see Section 3.5.2.3).  
Select <5RS232test> to run the COM1 and COM2 communications test (see Section 3.5.2.4).  
3.5.2.1  
<1COM1, 2COM2>  
The COMx ports can be set for specific communications settings. The settings  
are baud rate, parity, data bits and stop bits. The available options are:  
Baud  
300, 600, 1 200, 2 400, 4 800, 9 600, 19 200, 28 800, 38 400  
Parity  
NONE, ODD or EVEN  
Length  
Stop Bit  
7 or 8  
1 or 2  
The default is <2 400, E, 7,1> for both COM1 and COM2.  
The user can also specify one or two termination characters as well as define  
these characters. These are referred to as “Term1” and “Term2”. These define  
the characters that mark the end of commands that are sent to the RPM4. The  
RPM4 looks for an ASCII(13) (carriage return) to terminate a received command  
but responds with both and ASCII(13) (carriage return) and an ASCII(10) (line  
feed). There are no other options.  
3.5.2.2  
<3IEEE-488>  
The IEEE-488 port’s primary address can be set from 1 to 31 in this screen.  
The factory default value is 10. Secondary addressing is not used or supported.  
This address must not conflict with the address of any other device on the same  
IEEE-488 bus.  
The receiving terminating character must be a line feed and EOI. Carriage returns  
are ignored if received. The RPM4 sends a line feed and asserts the EOI line to  
terminate a reply. These settings are fixed to agree with IEEE Std. 488.2. If you  
change the address, the IEEE interface will reset (PON) and become idle.  
3.5.2.3  
<4FORMAT>  
The RPM4 has two different syntax formats available for the remote program  
commands.  
The classic remote command format is highly intuitive and conforms with  
previous DHI PPC and RPM products.  
The enhanced remote command format generally uses the same commands as  
the classic format, but in addition it follows the syntax, format, and status  
reporting features of IEEE Std 488.2.  
The details of each format are covered in Section 4.3.  
[SPECIAL], <2remote>, <4format> allows the remote program command  
syntax to be selected. The cursor is on the active format. Select <1classic> or  
<2enhanced> as desired.  
Page 63  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
3.5.2.4  
<5RS232 SELF-TEST>  
The RS232 self-test is provided to check the RPM4 COM ports and the interface  
cable independently of an external device or computer.  
If you are having difficulty communicating with RPM4 from a host computer  
using RS232, the RS232 self test can help establish that the RPM4 COM1 port  
you are trying to communicate with and the interface cable you are using are good.  
To run a self test of the RS232 ports (COM1 and COM2), press [SPECIAL],  
<2remote>, <5RS232test>.  
The display prompts you to connect COM1 to COM2 using a standard pin-to-pin  
DB-9F to DB-9M RS232 cable (see Section 4.2.1.1, 4.2.1.3).  
Once the cable has been installed, press [ENT] to run the self-test. The test is first  
executed in the COM1COM2 direction and then in the COM2COM1 direction.  
If the COM1COM2 test passes:  
<PASSED> displays briefly and the test  
proceeds to COM2COM1.  
If COM2COM1 passes:  
<PASSED> is displayed briefly followed  
by the conclusion, <The RS232 test has  
PASSED>.  
If a test fails:  
Execution is suspended until [ENT] is  
pressed.  
The RPM4 RS232 test can fail for three reasons:  
1. The RS232 cable being used is incorrect (Section 4.2.1.1, 4.2.1.3 for  
information on the correct cable).  
2. COM1 and COM2 do NOT have the same serial communications settings  
and therefore cannot communicate together (see Section 3.5.2.1 to set  
the COM ports).  
3. COM1 or COM2 is defective.  
The reason for failed communications is almost always a cable or incorrect  
RS232 interface settings. Be sure that these are correct before concluding  
that a COM port is defective.  
3.5.3  
<3HEAD>  
 PURPOSE  
To view or change the properties of the HEAD function (see Section 3.3.7) including the unit of  
measure of length for head height entry and the test fluid type and species for density calculations.  
 OPERATION  
From the MAIN RUN screen, pressure [SPECIAL], <3Head>.  
Select the desired height unit of measure and press [ENT].  
Select <1gas> or <2liqud> depending on the pressurized medium between the RPM4 and  
the height at which pressure is to be calculated. Select the gas or liquid species. The liquid  
selection <3User>, is to create a custom liquid with a user entered density.  
Use [HEAD] to set a head height if desired.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 64  
3. OPERATION  
3.5.4  
<4SDS>  
 PURPOSE  
To open and close SDS temporarily for the Hi or Lo Q-RPT or to turn the SDS function ON  
and OFF full time for the Hi or Lo Q-RPT.  
See Section 3.2.7 for complete information on RPM4’s SDS (Self Defense System) feature.  
 PRINCIPLE  
SDS is a self defense system to protect RPM4 Q-RPTs from overpressure (see Section 3.2.7).  
Normally, opening and closing SDS is performed automatically by the RPM4 or by the  
operator using the [SDS] key.  
[SPECIAL], <4SDS> gives further control over the SDS function.  
This includes:  
a) the possibility of temporarily opening or closing SDS on either the Hi or Lo Q-RPT (see  
Section 3.5.4.1), and; b) turning OFF SDS so that it is open full time and RPM4 can be  
operated as if SDS were not installed (see Section 3.5.4.2).  
The temporary opening or closing of SDS allows the SDS open/closed state to be set  
immediately to the desired state. Following the change, normal automated operation of SDS  
and control using the [SDS] key is still valid. This function is often used to open SDS on the  
inactive Q-RPT in PRM4s with dual Q-RPTs.  
Setting the SDS function to full time OFF eliminates the SDS function completely until is set  
to full time ON again.  
3.5.4.1  
<1TEMP OPEN/CLOSE>  

OPERATION  
See Section 3.2.7 for complete information on RPM4’s SDS (Self Defense  
System) feature.  
To temporarily open or close the SDS of the Hi or Lo Q-RPT press [SPECIAL],  
<4SDS>, <1temp open/close>. If the RPM4 has two Q-RPTs and both have  
SDS, the Q-RPT must then be selected. The next display is:  
The cursor is on the current state of SDS for the  
designated Q-RPT. Select <1close> to close  
SDS temporary:  
1close 2open  
Hi  
SDS or <2open> to open SDS and return to the  
MAIN RUN screen. [ESC] to return without  
making changes.  
If <2open> is selected and SDS for the Q-RPT is not already open, the SDS  
opening screen with indication of the maximum pressure of the Q-RPT is displayed.  
This is the same screen used when opening SDS using the [SDS] key (see  
Section 3.3.8). Check that the pressure applied to the Q-RPT module TEST(+)  
port does not exceed the Pmax! value before confirming that SDS should be opened.  
Opening SDS with a pressure greater than Pmax! applied to the test port  
may cause overpressure damage to the Q-RPT.  
Page 65  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
3.5.4.2  
<2FULL TIME ON/OFF>  

OPERATION  
See Section 3.2.7 for complete information on RPM4’s SDS (Self Defense  
System) feature.  
Turning SDS “full time OFF” for a Q-RPT module eliminates normal SDS  
operation so that the Q-RPT module TEST(+) port remains open. However,  
the SDS overpressure function (see Section 3.4.4.1) remains active.  
To turn SDS full time ON or OFF for a Q-RPT module, press [SPECIAL],  
<4SDS>, <2full time on/off >. If the RPM4 has two Q-RPTs and both have SDS,  
the Q-RPT must then be selected. The next display is:  
The cursor is on the current state of SDS for the  
designated Q-RPT. Select <1on> to set SDS for  
normal operation and return to the main run SDS full time:  
Hi  
1on 2off  
screen. Select <2off> to open SDS permanently  
so operation is as if SDS were not installed.  
[ESC] to return without making changes.  
If <2off> is selected and SDS for the Q-RPT is not already open, the SDS opening  
screen with indication of the maximum pressure of the Q-RPT is displayed. This is  
the same screen used when opening SDS using the [SDS] key (see Section  
3.3.8). Check that the pressure applied to the Q-RPT module TEST(+) port does  
not exceed the Pmax! value before confirming that SDS should be opened.  
Opening SDS with a pressure greater than Pmax! applied to the test port  
may cause overpressure damage to the Q-RPT.  
3.5.5  
<5PREFS>  
 PURPOSE  
To access a menu of RPM4 operational preferences and functions.  
 OPERATION  
1ScrSvr 2sound 3time  
4ID 5level  
To access the PREFS menu press [SPECIAL],  
<5prefs>. The display is:  
The PREFS menu includes:  
<1ScrSvr> View and change the screen saver activation time (see Section 3.5.5.1).  
<2sound>  
<3time>  
<4ID>  
View and change the keypress sounds (see Section 3.5.5.2).  
View and edit the internal time and date settings (see Section 3.5.5.3).  
View the RPM4 serial number (SN) and view or edit the ID number  
(see Section 3.5.5.4).  
<4level>  
View and set user security level and/or password (see Section 3.5.5.5).  
© 2004-2007 DH Instruments, a Fluke Company  
Page 66  
3. OPERATION  
3.5.5.1  
<1SCRSVR>  
PURPOSE  
To adjust the idle time after which RPM4’s SCREEN SAVER activates.  
PRINCIPLE  


RPM4 has a SCREEN SAVER function which causes the display to dim after a  
front panel key is NOT pressed for a certain amount of time. The default is for the  
screen saver to activate after 10 idle minutes. The screen saver activation time  
can be adjusted by the user or screen saving can be completely eliminated.  
Setting screen saver time to zero eliminates the SCREEN SAVER function so  
that the display permanently remains at full brightness.  

OPERATION  
To access the SCREEN SAVER function, press [SPECIAL], <5prefs>,  
<1ScrSav>. Edit, in minutes, the idle time after which screen saver will activate  
to dim the screen. Set the time to zero to eliminate the SCREEN SAVER function.  
3.5.5.2  
<2SOUND>  

PURPOSE  
To adjust or suppress the RPM4 valid key press sound.  
PRINCIPLE  

RPM4 provides audible feedback by a brief “beep” when a valid key press is  
made. The tone frequency of this beep may be selected from three choices or it  
may be completely suppressed. Invalid key presses are indicated by a  
descending two tone “blurp” which cannot be suppressed.  

OPERATION  
To access the keypad sound adjustment function press [SPECIAL], <5prefs>,  
<2sound>.  
Select between <2lo>, <3mid> or <4hi> to adjust the valid key press tone frequency.  
Select <1none> to suppress the valid key press tone.  
The sound function only affects the valid key press tone. The invalid key  
press tone and other RPM4 sounds cannot be adjusted or suppressed.  
3.5.5.3  
<3TIME>  

PURPOSE  
To view and edit the RPM4 internal time and date settings.  

OPERATION  
access the  
To  
TIME  
function  
Edit: 1time 2date  
press [SPECIAL], <5prefs>, <3time>.  
08:32:11 am 20030125  
The display is:  
Page 67  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
Select <1time> to edit the time. Edit hours, then minutes, then am/pm by  
pressing [ENT] after each entry. Seconds go to zero when minutes are entered.  
This can be used to synchronize the time with a time standard.  
Select <2date> to edit the date. The date must be specified in YYYYMMDD format.  
The RPM4 date and time are set to United States Mountain Standard Time  
in the final test and inspection process at the factory. If desired, use the  
TIME and DATE function to set your local time and date.  
3.5.5.4  
<4ID>  

PURPOSE  
To view or edit the RPM4 user ID and to view the RPM4 serial number.  
OPERATION  

To access the ID function press [SPECIAL] and select <5prefs>, <2ID>.  
Select <1view> to view the current ID.  
Select <2edit> to edit the ID.  
The ID has twelve characters. When the edit screen is opened, the cursor is on  
the first character. Numerical values can be entered directly from the keypad. In  
addition, the cursor control keys can be used to toggle through a list of available  
alphanumeric characters. Holding the key slews through the characters.  
Character order going up is: blank space, symbols, lower case letters, upper  
case letters, numbers. After selecting a character, press [ENT] to activate it and  
move to the next character field.  
When a character is selected the cursor moves to the next character. To leave a  
blank character, press [ENT] with the field for that character blank. Use this for  
the trailing characters if the ID being entered is less than twelve characters.  
After the last of the twelve characters has been entered, the <Save ID?> option is offered.  
Select <1no> to return to the ID edit screen. Select <2yes> to save the edited ID.  
The ID can be set remotely from a computer which is quite a bit more  
convenient than entering characters from the keyboard (see Section 4.4.4,  
ID command). The ID is not cleared or reset by any RESET function  
(see Section 3.5.9).  
3.5.5.5  
<5LEVEL> (SECURITY)  

PURPOSE  
To set user protection levels to restrict access to certain functions and to edit the  
password required for changing user levels.  

PRINCIPLE  
RPM4’s front panel user interface provides the means to access all RPM4 user  
defined data, settings and functions including calibration data. Inadvertent,  
uninformed or unauthorized altering or deleting of data, settings and functions  
could require extensive reconfiguration by the user and might cause invalid  
readings and behavior. For these reasons, depending upon the application in  
which RPM4 is being used, it may be desirable to restrict access to some  
functions. The user level function provides a means of restricting access to certain  
functions. Four different levels of security are available.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 68  
3. OPERATION  
Access to changing security levels can be left open, or be protected by a password.  
Security Levels  
The security levels are structured to support typical operating environments as follows:  
None  
Low  
This level is intended for use only by the system manager and/or  
calibration facility. It allows access and editing in all areas including  
critical metrological information.  
Low security is designed to protect the specific metrological  
information and SYSTEM DIAGNOSTIC AND MAINTENANCE  
functions of the system against accidental alteration. It is intended for  
an advanced operator performing many different tasks. Low security  
is the default user level setting.  
Medium  
High  
Medium security is designed to protect specific metrological  
information in the system and to assure that the RPM4 is operated  
using consistent operational parameters.  
High security is designed to protect all operating parameters. It is  
intended to minimize operator choices, for example to perform  
repeated identical calibrations under consistent conditions.  
RPM4 is delivered with the security level set at low to avoid inadvertent  
altering of critical internal settings but with access to changing security  
levels unrestricted. It is recommended that the low security level be  
maintained at all times. If there is a risk of unauthorized changing of the  
security level, changing authority should be password protected  
(see  OPERATION of this section).  
The security levels are structured to support typical levels of operation as shown  
in Table 8. Specifically, the security levels prevent execution of the functions  
accessed by the key strokes marked by “•”:  
Page 69  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
Table 8. Security Levels  
FUNCTION  
LOW  
MEDIUM  
HIGH  
[RANGE]  
[ENT] (AutoTest)  
[UNIT]  
[MODE]  
[AutoRange]  
[LEAK CK]  
[DISPLAY]  
[HEAD]  
[SDS]  
[AutoZ] (in absolute mode)  
[SETUP]  
[SETUP], <1range>  
[SETUP], <2res>  
[SETUP], <4UL>  
[SPECIAL]  
[SPECIAL], <1AutoZ>  
[SPECIAL], <1AutoZ>, <1on/1off>  
[SPECIAL], <1AutoZ>, <3edit>  
[SPECIAL], <2remote>  
[SPECIAL], <2remote>, make changes  
[SPECIAL], <3head>  
[SPECIAL], <4SDS>  
[SPECIAL], <5pref>, <1ScrSvr>  
[SPECIAL], <5pref>, <2sound>  
[SPECIAL], <5pref>, <3time>  
[SPECIAL], <5pref>, <3time>, make changes  
SPECIAL], <5pref>, <4ID>, <2edit>  
[SPECIAL], <6Punit>  
[SPECIAL], <7internal>  
[SPECIAL], <7internal>, <3RPT2x>  
[SPECIAL], <7interrnal>, <5log>, clear log  
[SPECIAL], <8cal>  
[SPECIAL], <8cal>, <2edit> under any selection  
[SPECIAL], <4reset>  
[SPECIAL], <4reset>, <4cal>  
[SPECIAL], <4reset>, <5all>  
Remote communications disabled  
“•” indicates the function/menu is NOT accessible.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 70  
3. OPERATION  

OPERATION  
RPM4 is delivered with no active password and access to the User Level menu is  
open. The user level is set to <1Low>. User levels can be changed freely until a  
password has been created.  
To  
access  
the  
LEVEL  
function  
1change user level  
2edit password  
press [SPECIAL], <5prefs>, <5level>.  
The display is:  
Restrictions: 1none  
2low 3medium 4high  
Selecting <1change user level> brings  
up the restriction menu:  
The cursor is on the current restriction level. Select a different level or  
or [ESC] back to the MAIN RUN screen.  
If no password is active, selecting  
<2edit password> displays the user  
password and allows it to be edited.  
Password: pppppp  
0 disables password  
Once a password has been entered, the user level cannot be changed without  
reentering the password.  
Passwords can be up to six numbers in length and cannot start with a zero.  
If <0> is entered, the password is made inactive and the user will not be required  
to enter a password to access the user level menu. This condition, with a  
security level of <2low>, is the factory default.  
If there is an active password, the  
RPM4 password entry screen appears.  
The user must enter the user defined  
password or the factory secondary  
RPM4 SNnnnn-xx  
Password: pppppp  
password to proceed further:  
The first field, <nnnn>, is the serial number of the RPM4, followed by a second field,  
<xx>, that represents the number of times that a secondary password has been  
used. The second field, <xx>, increments each time a secondary password is  
used. The third field, <pppppp> is for user entry of the normal password.  
The factory secondary password is available in case the user’s password has  
been misplaced or forgotten. It can be obtained by contacting a DHI  
Authorized Service Center (see Table 29). The factory secondary password  
is different for all RPM4’s and changes each time it is used.  
3.5.6  
<6PUNIT>  
 PURPOSE  
To customize the selection of pressure units of measure that are available in the [UNIT] key menu.  
Page 71  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
 PRINCIPLE  
The [UNIT] function key makes available a choice of six default pressure units (US or SI units  
depending on whether the RPM4 has been factory set as US or SI) (see Section 3.3.2).  
RPM4 also supports many commonly used units other than those included in the default set up.  
These units can be made available for active selection by customizing the UNIT function  
using [SPECIAL], <6PresU>. This allows RPM4 to offer a very wide selection of units while  
simplifying day to day operation. The typical user customizes the [UNIT] function key to  
support his/her six most commonly used units.  
 OPERATION  
To customize the [UNIT] function key, from the MAIN RUN screen press [SPECIAL],  
<6PresU>. The display is:  
1. Entry field to specify which unit position (1 to 6) of the [UNIT]  
Set up unit #6  
function key menu is to be changed.  
Unit#6 1SI 2other  
3altitude 4user  
Enter the number of the unit position that you would  
like to change. The display becomes:  
Select the desired pressure unit category (SI units include units based on SI units such as  
mmHg), then select the desired unit from the unit menu.  
The units of measure available are listed in Table 9.  
Table 9. UNIT Function - Available Units of Measure  
<1SI>  
<2OTHER>  
<3ALTITUDE>  
<4USER>  
<1Pa>  
<2hPa>  
<1psi>  
<2psf>  
<1feet>  
<2meters>  
<3kPa>  
<3inHg>  
<4inWa>  
<5kcm2>  
<6Torr>  
<7mTor>  
<4MPa>  
<5mbar>  
<6bar>  
<7mmHg>  
<8mmWa>  
If <4user> is selected, the user unit must be defined. The display is:  
Define user unit:  
1.000000 unit/Pa  
1. Entry field.  
Enter the number of user units per Pascal (Pa) in the entry field. Pressing [ENT] defines the  
user unit and returns to the <Set up unit #n> screen.  
The user defined unit label can be customized to any alphanumeric, four character label  
using the remote command “UDU” (see Section 4.4.4).  
See Section 7.2.1 for the pressure unit conversion factors used by RPM4.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 72  
3. OPERATION  
3.5.7  
<7INTERNAL>  
 PURPOSE  
To view, set, adjust, and maintain various aspects of RPM4’s internal operation.  
 OPERATION  
1baro 2ReadRt 3RPT2x  
4lo vnt 5log  
To access the internal selections press [SPECIAL],  
<7internal>. The display is:  
The INTERNAL menu choices include:  
<1baro>  
View the real time output of the on-board barometer, if present (see Section  
3.5.7.1).  
<2ReadRt>  
<3RPT2x>  
Turn ON and OFF RPM4’s automated, rate of change dependent, reading  
integration rate feature (see Section 3.5.7.2).  
Enable and disable RPM4 parallel measurement mode in which two Q-RPT  
modules are used to measure in parallel and their readings are averaged  
(see Section 3.5.7.3).  
<4lo vnt>  
<5log>  
Operate Q-RPT module Gxxx and BGxxx low VENT valve directly  
(see Section 3.4.7.4).  
View the RPM4 incident log (see Section 3.5.7.5).  
3.5.7.1  
<1BARO>  

PURPOSE  
To view the value of atmospheric pressure as measured by the RPM4 on-board  
barometer.  
There is no on-board barometer in RPM4’s that have Gxxx (gauge) internal  
Q-RPTs only.  

PRINCIPLE  
RPM4’s that include an Axxx (absolute) and/or BGxxx (bi-directional gauge)  
Q-RPT are equipped with a separate, on-board barometer. The atmospheric  
pressure measurements made by the on-board barometer are used for dynamic  
compensation of atmospheric pressure when using an Axxx Q-RPT to make gauge  
pressure measurements (see Sections 3.3.3,  PRINCIPLE and 3.2.2) and for static  
pressure compensation when using a G15K or BG15K Q-RPT.  
See Section 5.5, Figure 7 and Section 5.6, Figure 8 for a photo and  
schematics showing the position of the on-board barometer in RPM4.  
The on-board barometer is a low accuracy sensor used only for measuring  
small changes in atmospheric pressure over short periods of time  
(see Section 3.2.2) and for line pressure compensation when using a G15K or  
BG15K Q-RPT. RPM4 measurement uncertainty does not depend on the  
measurement uncertainty of the on-board barometer.  
Page 73  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  

OPERATION  
RPM4’s that have only G100K or G200K Q-RPTs (no Axxx, G15K or BG15K)  
are NOT equipped with an on-board barometer.  
To view the current reading of the on-board barometer press [SPECIAL],  
<7internal>, <1baro>. The display is in the active pressure unit of measure  
(see Section 3.3.2). The display resolution is fixed to 0.01 Pa, or its equivalent.  
3.5.7.2  
<2READRT>  

PURPOSE  
To turn ON and OFF RPM4’s automated, rate of change dependent, reading  
integration rate feature.  

PRINCIPLE  
To obtain maximum resolution from RPM4 Q-RPT pressure measurements, an  
integration time of about 1.2 second per reading is used. In most situations,  
maximum precision is needed when pressures are stable so a relatively slow  
display update rate presents no disadvantage. However, when pressure is  
changing quickly, more rapid pressure updates are usually more important than  
obtaining maximum precision on individual readings. The RPM4 read rate  
function automatically adjusts pressure measurement integration time depending  
on the rate of change of pressure. When pressure is changing rapidly, reading  
rate is increased. When pressure is evolving slowly, reading rate is decreased  
and maximum precision is obtained.  
When the automated read rate function is ON, three pressure rate of change  
dependent read rates are used. The result is three display update rates:  
Table 10. READRT - Display Update Rates  
PRESSURE  
RATE OF CHANGE  
DISPLAY  
UPDATE  
> 3 % of range span/s  
0.2 s  
0.6 s  
1.2 s  
> 0.5 and < 3 % of range span/s  
< 0.5 % of range span/s  
For situations in which maximum reading precision is desired regardless of pressure  
rate of change, the RPM4 automated read rate function can be turned OFF.  
In this case, the reading rate is always the high resolution rate of about 1.2 readings  
per second.  

OPERATION  
To turn the automated read rate function ON or OFF or check its current status,  
press [SPECIAL], <7internal>, <3ReadRt>.  
Auto read rate:  
The display is:  
1on 2off  
The cursor is on the current selection.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 74  
3. OPERATION  
Selecting <1on> activates the automated reading rate and returns to the MAIN  
RUN screen. Selecting <2off> turns OFF the automated reading rate and  
returns to the MAIN RUN screen.  
The default RPM4 condition is auto read rate ON.  
Auto read rate ON/OFF is NOT Q-RPT or range specific. Turning auto read  
rate ON or OFF in one range turns it ON or OFF for all RPM4 ranges.  
3.5.7.3  
<3RPT2X>  

PURPOSE  
To enable and disable the RPM4 parallel measurement mode in which two  
Q-RPT modules are used to measure in parallel and their readings are averaged.  

PRINCIPLE  
RPM4s that have two Q-RPT modules of the same type (Axxx, Gxxx or BGxxx)  
support parallel measurement mode. In this mode, both Q-RPTs are used to  
measure the same pressure in parallel and their readings are averaged.  
Parallel measurement mode sets up a third Q-RPT designated HL (combination  
of Hi and Lo). The HL RPT can be selected by the [RANGE] function and  
supports other RPM4 functions such as UNIT, MODE and DISPLAY.  
When parallel measurement mode is set up, the resulting HL Q-RPT can be a  
third Q-RPT in addition to the Hi and Lo RPTs. It is also possible to make the HL  
Q-RPT the sole Q-RPT, suppressing the Hi and Lo Q-RPTs. This feature is used  
when an RPM4 will always be used in parallel measurement mode and the  
availability of the individual Hi and Lo Q-RPTs is not desired.  
[SPECIAL], <7internal>, <3RPT2x> is used to set up or suppress parallel  
measurement mode in RPM4s that support it.  
In parallel measurement mode, the maximum pressure is the maximum  
pressure of the Lo Q-RPT.  

OPERATION  
Parallel measurement mode is only available on RPM4s with two Q-RPTs of  
the same type (Axxx, Gxxx, BGxxx).  
To access the parallel measurement mode enable/disable function press  
[SPECIAL], <7internal>, <3RPT2x>.  
The cursor is on the number corresponding to the current setting.  
Select <1off> to disable parallel measurement mode. This will eliminate the HL  
Q-RPT.  
Select <2on> to enable parallel measurement mode. This creates the HL  
parallel mode Q-RPT. The Hi and Lo Q-RPTs are also still available.  
Select <3on, w/ Hi & Lo RPT off> to enable parallel measurement mode and  
disable access to the Hi and Lo Q-RPTs individually. This creates the HL  
parallel mode Q-RPT and makes it the sole Q-RPT available for selection.  
When using parallel measurement mode, if RPM4 detects an excessive  
difference between the pressure measured by the Hi and Lo Q-RPTs, a warning  
is given by rapid beeps for 8 seconds and displaying <Check RPT connection>.  
Page 75  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
Operation returns to normal when the disagreement between the two Q-RPTs  
returns to normal.  
When using parallel measurement mode, the Hi and Lo Q-RPTs should be  
connected IN PARALLEL to the pressure to be measured (both Q-RPTs  
connected to the same pressure). The measured pressure indicated in  
parallel measurement mode is the average of the Hi and Lo Q-RPTs.  
3.5.7.4  
<4LO VNT>  

PURPOSE  
To cause an RPM4’s Gxxx or BGxxx Q-RPT TEST(-) vent valve to stay open or  
closed rather than open and close automatically.  
This feature is active only when the active Q-RPT is a Gxxx (gauge) or  
BGxxx (bi-directional gauge) Q-RPT.  

PRINCIPLE  
An RPM4 equipped with a Gxxx (gauge) or BGxxx (bi-directional gauge) Q-RPT has  
a TEST(-) vent valve in its Q-RPT module (see Figure 8, Gxxx, BGxxx, Valve C).  
The TEST(-) vent valve is used to open the TEST(-) port to atmosphere which  
also connects the Q-RPT and the device or system under test low side to atmosphere.  
In normal RPM4 operation, the TEST(-) valve is closed to isolate the low pressure  
circuit from fluctuations in ambient pressure when the Q-RPT is being used to  
measure pressure. It is open only when SDS is closed (see Section 3.2.7).  
However, it may be desirable to open the TEST(-) port to atmosphere while  
measuring pressure and/or without closing SDS. For example, this may be  
necessary to assure that the pressure on the low side of the Q-RPT and the  
system under test does not move too far away from atmosphere. [SPECIAL],  
<7internal>, <4lo vnt> allows the TEST(-) vent valve to be set to be  
permanently open, permanently closed or to operate in its default, automated  
condition. It also allows the current status of the valve to be viewed.  

OPERATION  
The normal, default setting for the TEST(-) vent valve is <1auto> in which RPM4  
automatically controls the valve based on current Q-RPT module operation.  
Setting other than <1auto> should only be selected by advanced users.  
To access the LO VNT function press [SPECIAL], <7internal>, <4lo vent>. If the  
RPM4 does not have a Gxxx (gauge) or BGxxx (bi-directional gauge) Q-RPT, the  
display is: <Available with Gxxx or BGxxx Q-RPT only>. If the RPM4 has  
more than one Gxxx or BGxxx Q-RPTs, the Hi or Lo Q-RPT must be selected.  
Test(-) vent:1auto  
The next display is:  
2open 3close 4view  
Select <1auto> for the TEST(-) vent valve operation to be controlled automatically  
by RPM4 based on current operation. This is the default and recommended setting.  
Select <2open> to cause the TEST(-) valve to open and remain open regardless  
of RPM4 operation until the setting is changed. If RPM4 detects a condition  
© 2004-2007 DH Instruments, a Fluke Company  
Page 76  
3. OPERATION  
in which it determines there could be a risk of overpressure to the Q-RPT  
by opening the TEST(-) vent valve, the message <Cannot open lo vent,  
DP overpressure risk> is displayed. If this message is displayed, return to  
normal operation, vent the RPM4 Q-RPT module and try again.  
Select <3close> to cause the TEST(-) vent valve to close and remain closed  
regardless of RPM4 operation until the setting is changed.  
Select <4view> to view the current condition of the TEST(-) valve. The display  
indicates whether current valve operation is controlled by the RPM4  
(<Auto TEST(-) vent>) or has been set manually (<Manual TEST(-) vent>)  
followed by the current valve status (<Open> or <Close>).  
If the RPM4 is being used as an external device to a PPC3 pressure controller  
(see Section 3.5.7.4), the Lo Vent setting may be changed from the PPC3  
(see the PPC3 Operation and Maintenance Manual).  
3.5.7.5  
<5LOG>  

PURPOSE  
To view and/or clear the RPM4 event log.  
PRINCIPLE  
RPM4 records to a log each time one of the following events occurs:  

Pmax! of an internal RPM4 Q-RPT or utility sensor is exceeded (see Section  
3.4.4.1).  
A memory fault occurs.  

OPERATION  
To view the event log press [SPECIAL], <9Log>.  
Use [ ] and [ ] to move back and forth between older and newer log entries.  
Each log entry has two screens, one with the event description and one with the  
even time and date. Use [ ] and [ ] to toggle between the two screens. The  
oldest logged event appears.  
After the last log has been viewed, the option to clear the log, <1no>, <2yes> is  
presented. Use <2yes> to remove all entries from the log. Use <1no> to  
continue without altering the log.  
To leave the log, use [ESC].  
3.5.8  
<8CAL>  
 PURPOSE  
To calibrate the RPM4 Hi and Lo Q-RPTs and adjust the on-board barometer. These  
functions are considered part of RPM4 maintenance and are covered in the maintenance  
section of this manual (see Sections 5.2, 5.3).  
 PRINCIPLE  
See Sections 5.2, 5.3.  
 OPERATION  
See Sections 5.2, 5.3.  
Page 77  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
3.5.9  
<9RESET>  
 PURPOSE  
To reset various RPM4 settings to default or factory values.  
 PRINCIPLE  
RPM4 stores its user definable settings in non-volatile memory. The reset menu allows the  
user to selectively or completely reset these settings to factory defaults. This clears any  
settings that the user has made, and should be used only to restore the RPM4 to a known  
state. RPM4 goes through its power up sequence after any type of reset is executed.  
RPM4 reset functions will change current settings to factory defaults. These may include  
settings vital to RPM4 operation and affecting the calibration of the quartz reference  
pressure transducers (Q-RPTs). Reset functions should only be used by qualified personnel  
with knowledge of reset consequences. Reset functions should never be used “experimentally”.  
 OPERATION  
1sets 2units 3ATest  
4cal 5all  
To access the RESET menu, press [SPECIAL],  
<9reset>. The display is:  
RESET menu choices include:  
<1set>  
to reset general system operating parameters (see Section 3.5.9.1).  
<2units> to reset unit of measure functions (see Section 3.5.9.2).  
<3ATest> to reset AutoTest parameters and clear the AutoTest data log (see Section 3.5.9.3).  
<4cal>  
<5all>  
to reset internal calibration coefficients and modes (see Section 3.5.9.4).  
to reset all settings except ID and security password to factory default values  
(see Section 3.5.9.5).  
3.5.9.1  
<1SETS>  

PURPOSE  
Sets most general operating parameters back to default values. Does not affect  
calibration coefficients, remote interfaces or AutoRange ranges. The Reset – Sets  
resets are itemized in Table 11.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 78  
3. OPERATION  
Table 11. Reset – Sets  
RESET  
[UNIT]  
RESULT  
SEE SECTION  
Pressure unit of measure to first of the six available  
3.3.2  
Measurement mode to the native mode of the Q-RPT  
Hi Q-RPT default range  
3.3.3  
3.3.1  
3.3  
[MODE]  
[RANGE]  
[HEAD]  
0 cm height and Nitrogen medium  
Stability Limit  
Upper Limit  
Resolution  
AutoZ  
0.005 % of Hi Q-RPT default range  
3.4.3  
3.4.4  
3.4.2  
3.5.1  
Hi Q-RPT default range default value  
0.001 % FS of Hi Q-RPT default range  
AutoZ ON for all Q-RPTs and measurement modes.  
Zoffset value not affected  
AutoZ  
3.5.1, 3.2.2  
3.3.5  
P
atm,0 set to 101.325 kPa a  
Leak Check  
Screen Saver  
Key Sounds  
Lo Vnt  
15 second run time. Clear logged results  
10 minutes to activation  
Medium tone valid key press sound  
Automatic  
3.5.5.1  
3.5.5.2  
3.5.7.4  
3.5.7.2  
ReadRate  
Automatic  
3.5.9.2  
<2 UNITS>  

PURPOSE  
Sets the six pressure units available under the UNIT function to the SI or US  
default selections depending on whether the RPM4 has been factory set for SI or US  
(see Section 3.3.2).  
Sets the user defined unit to 1.000/Pa (see Section 3.5.6).  
Sets the reference temperature for inWa unit to 20°C.  
3.5.9.3  
<3ATEST>  

PURPOSE  
Resets Auto Tests to default characteristics (see Section 3.3.10).  
Clears AutoTest data log (see Section 3.4.5).  
3.5.9.4  
<4 CAL>  

PURPOSE  
The Reset - Cal function will reset Q-RPT, utility sensor and barometer  
calibration coefficients and settings and reset AutoZ values to zero. This  
will change the RPM4 calibration and could cause it to make out of tolerance  
measurements.  
Clears all user values affecting the calibration of Q-RPTs and the on-board  
barometer. The Reset – Cal resets are itemized in Table 12.  
Page 79  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
Table 12. Reset – Cal  
RESET  
RESULT  
SEE SECTION  
All Q-RPT Calibration  
Coefficients  
PA to zero, PM to 1  
5.2.1.1, 5.2.7  
Axxx Q-RPT absolute and  
negative gauge mode  
ON  
5.2.5  
5.3  
On-board Barometer  
Calibration Coefficients  
PA to zero, PM to 1  
Set all dates to 19800101  
Calibration Date  
AutoZ values  
5.2.7, 5.3  
3.5.1  
Axxx Q-RPTs: All Poffset values to zero for  
absolute mode and 101325 Pa for gauge and  
negative gauge modes  
Gxxx, BGxxx Q-RPTs: All Poffset values to zero  
ON, all Q-RPTs, all measurement modes  
AutoZ function  
3.5.1  
3.5.9.5  
<5 ALL>  

PURPOSE  
The reset - all function clears and deletes large amounts of user defined  
information including critical calibration data.  
Combines all resets in one global reset command that clears the entire user  
section of non-volatile memory except the ID function (see Section 3.5.5.4) and  
the security level password (see Section 3.5.5.5) returning RPM4 to the  
“as delivered” condition. The Reset – All resets are itemized in Table 13.  
Table 13. Reset – All  
RESET  
Reset – Sets  
RESULT  
All the resets of Reset - Sets  
All the resets of Reset - Units  
All the resets of Reset - ATest  
All the resets of Reset - Cal  
SEE SECTION  
3.5.9.1  
Reset – Units  
Reset – Atest  
Reset – Cal  
3.5.9.2  
3.5.9.3  
3.5.9.4  
Remote Interfaces  
COM1, COM2 and IEEE-R88 interfaces to  
default settings.  
3.5.2  
Remote Communications  
Level (Security)  
Remote command format to Classic  
Reset security level to low  
Off  
3.5.2.3  
3.5.5.5  
3.5.7.3  
3.5.4.2  
Parallel Measurement Mode  
SDS  
All SDS full time ON  
© 2004-2007 DH Instruments, a Fluke Company  
Page 80  
4. REMOTE OPERATION  
4. REMOTE OPERATION  
4.1  
OVERVIEW  
Most of the RPM4 front panel functions can also be executed by commands from a remote computer.  
The host computer can communicate to the RPM4 using the RPM4’s COM1 RS232 port or it’s IEEE-488 port.  
Before writing test code using RPM4 remote commands, familiarize yourself with its operating principles  
by reading Section 3 of this manual.  
4.2  
INTERFACING  
Sending a program message to the RPM4 places it into remote mode. The remote indicator to the right  
of the display window lights when the RPM4 is in remote mode. It also flickers when a program message  
is received. The menus usually accessed from the front panel are locked out while in remote. The [ESC]  
key returns the RPM4 to local operation unless the <REMOTE> program message, which locks out all  
keypad operation, was sent to the unit.  
4.2.1  
RS232 INTERFACE  
4.2.1.1  
COM1  
The RPM4 COM1 RS232 interface is located on the back of the unit. It is a 9-pin  
male DB-9F connector configured as a DCE device. Data is transmitted out of  
the unit using pin 2, and is received on pin 3. This allows a normal pin-to-pin  
DB-9M to DB-9F RS232 cable to be used to connect to a DTE host.  
Handshaking is not required or supported. The COM1 receive buffer is  
80 bytes deep. If you overflow the buffer by sending too much data, the data will  
be lost. Because of this, you must send a single program message at a time  
and you must wait for the RPM4 to reply from the previous command before  
issuing another command.  
Table 14. COM1 Pin Designations and Connections  
RPM4 COM1 DB-9F PIN DESIGNATIONS  
PIN #  
FUNCTION  
DESCRIPTION  
2
3
5
TxD  
RxD  
Grn  
This pin transmits serial data from the RPM4 to the host.  
This pin accepts serial data from the host computer.  
This pin is the common return for the TxD and RxD signals.  
IBM PC/XT DB-9F  
CONNECTIONS  
IBM PC/XT DB-9M TO RPM4 DB9F  
CONNECTION  
DB-25M  
DB-9F  
DB-9M  
DB-9F  
2
3
7
3
2
5
3
2
5
3
2
5
Page 81  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
4.2.1.2  
IEEE-488  
The RPM4 IEEE-488 interface is located on the back of the unit. The physical  
and electrical interface conforms to IEEE Std 488.1-1987 Subset E2 and IEEE  
Std. 488.2-1992. You should not attempt to communicate with the IEEE-488  
interface while using the COM1 interface. The IEEE-488 receive buffer is 250  
bytes deep. If you attempt to overflow the buffer, the RPM4 will hold off release  
of the NRFD handshake line until it can service and empty the receive buffer.  
This keeps the buffer from overflowing. It is recommended that you check for  
errors using the “ERR?” query after sending a group of non-query program  
messages. When using queries, ensure that you wait for a reply to each query to  
ensue proper operation and order of command execution. Replies to queries  
remain in the reply queue until the host gets them, so they can “stack up”,  
causing replies to appear out of sequence.  
4.2.1.3  
COM2  
The RPM4 COM2 RS232 interface is located on the back of the unit. It can be used  
to allow the host computer to communicate with another device through the RPM4.  
This allows the user to use one host COM port to communicate with the RPM4 and  
an additional RS232 device. Refer to the “#” remote program command for  
details. When using the RPM4 as a reference for a PPC3, another RPM4 can be  
connected to the first RPM4’s COM2 port, allowing the PPC3 to communicate  
with both RPM4s (see Section 3.2.5).  
COM2 is a 9-pin female DB-9F connector configured as a DTE device. Data is  
transmitted out of the RPM4 using pin 3, and is received on pin 2. This allows a normal  
pin-to-pin DB-9M to DB-9F RS232 cable to be used to connect to a DCE device.  
Handshaking is not required or supported.  
Table 15. COM2 DB-9F Pin Designations  
PIN #  
FUNCTION  
DESCRIPTION  
2
3
4
5
RxD  
TxD  
DTR  
Grn  
This pin transmits serial data from the RPM4 to a device.  
This pin accepts serial data from the external device.  
This pin is Data Terminal Ready (DTR) (held at + 5 V).  
This pin is the common return for the TxD and RxD signals.  
4.3  
PROGRAMMING FORMATS  
RPM4 supports two program message formats, the “classic”, and the “enhanced” formats. The user  
must select which format to use. Selection can be accomplished from the front panel (see Section  
3.5.2.3) or remotely using the “L2” or “L3” program message (see Section 4.4.4). The ”MSGFMT”  
command can also be used to select the format, but is not recommended for new designs.  
The main difference between the “classic” and “enhanced” formats is that when using the IEEE-488 interface,  
a query operator “?” must be included in an enhanced command to yield a reply from the RPM4. When  
using the COM1 port in classic or enhanced mode or using the IEEE-488 port in classic mode, every  
command has a reply which the host must wait for before continuing. In addition, the enhanced message  
format supports IEEE Std 488.2 syntax, format and status reporting. The default is the classic format.  
In either format, it is recommended that you start out a command sequence with the “*CLS” command,  
which clears all of the communication and error queues. The basic commands are similar for both the  
classic and enhanced formats, but the usage, syntax, format and status reporting are different.  
Many RPM4 classic and enhanced commands are common with PPC2+, PPCK+ and PPC3  
Pressure/Controller Calibrators.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 82  
4. REMOTE OPERATION  
4.3.1  
CLASSIC PROGRAM MESSAGE FORMAT  
Each program message sent is also a query. You can only send one program message to  
the RPM4 at time. After sending any program message, you must wait for the RPM4 to reply  
before sending another program message. This reply will contain data, or a numeric error  
message if the program message was invalid. You must wait for this reply before issuing  
another program message to the RPM4. This insures that the RPM4 has completed the  
program message. Most remote program messages will return a reply within 500 ms except:  
“PR?”, “PRR?”, “SR?”, “ATM?”, “RATE?”: Up to 2 seconds.  
“RPT”, “ARANGE”, “AUTOZERO=RUN”: Up to 3 seconds  
The syntax and format used for each program message in the classic mode is listed next to  
the keyword “Classic”’ in each program message summary in Section 4.4.4.  
4.3.2  
ENHANCED PROGRAM MESSAGE FORMAT  
The enhanced program message format uses the IEEE Std. 488.2 format, syntax and status  
reporting. Errors are reported using the IEEE Std. 488.2 status reporting model. If an error is  
reported, the error is put into an Error Queue and the “ERR?” query program message can  
be used to get a text description of the most recent error. If you are using the IEEE-488 port,  
the service request line can be setup to be asserted if this occurs (see Section 4.5.2). In the  
enhanced format, there are two possible program message types for every program  
message. Each of these two types starts with the same basic text referred to as the program  
message header. The two types are COMMAND type and QUERY type commands.  
4.3.2.1  
USING COMMAND TYPE COMMANDS  
Enhanced format commands DO NOT reply when using the IEEE-488  
interface unless a “?” is included in the command. Do not expect a response  
from the RPM4’s IEEE-488 interface to non-query (no “?”) commands as  
there is none. Remote software will time-out waiting for a response from  
RPM4. However, in RS232 communications, there is always a response and  
the response MUST be read prior to issuing another command.  
The COMMAND type of program message executes a process and can  
additionally send data to the RPM4 in the form of comma delimited arguments.  
This data is usually a setting of some sort that is stored in the RPM4. If data is  
specified, it must be preceded by at least one white space from the program  
message header and be within the range and format described in the program  
message description. The keyword “Command:” appears to the left of the  
required syntax in each program message description in Section 4.4.4.  
If you are using the IEEE-488 port, the Command type does not generate a reply  
unless you place a query operator “?” immediately after the command. You also  
may send multiple program messages at once by separating each program  
message with a semicolon. The commands are queued and executed in as  
received order after the entire message stream has been received, so care in  
determining order of execution is needed.  
If you are using the RS232 port COM1, the Command type will always generate  
a reply so you must wait for a reply before issuing another program message.  
Because of this, you can only send one Command program message at a time  
while using the COM1 port.  
Page 83  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
Examples:  
IEEE-488 enhanced mode command series using query operator:  
“*CLS?” (Clear the error queue. Wait for reply)  
“UNIT? KPA” (Generates a reply. User must wait for reply before continuing)  
“MMODE? A” (Generates a reply. User must wait for reply before continuing)  
“PR?”  
IEEE-488 enhanced mode commands without query operator:  
“*CLS” (Clear the error queue. No reply)  
(Generates a reply. User must wait for reply before continuing)  
“UNIT KPA” (No reply)  
“MMODE A” (No reply)  
“ERR?”  
(Wait for reply. User should use “ERR?” query following a  
series of non query commands to check for errors that may  
have occurred)  
IEEE-488 enhanced mode multiple commands without query operator:  
“*CLS”  
(Clear the error queue. No reply)  
(Two command at once. No reply)  
“UNIT KPA;MMODE A”  
“ERR?”  
(Wait for reply. User should use “ERR?”  
query following a series of non query  
commands to check for errors that may  
have occurred)  
COM1 enhanced mode command:  
“*CLS” or “*CLS?”  
(Clear the error queue. Wait for reply)  
“UNIT KPA” or “UNIT? KPA” (Generates a reply. User must wait for  
reply before continuing)  
“MMODE A” or “MMODE? A” (Generates a reply. User must wait for  
reply before continuing)  
“PR” or “PR?”  
(Generates a reply. User must wait for  
reply before continuing)  
4.3.2.2  
USING QUERY TYPE COMMANDS  
The QUERY type of program message just requests data from the RPM4.  
Placing the query operator “?” immediately after the command creates a query.  
You must wait for a reply with a query. If you send any type of program  
message to the RPM4 after a query before receiving a reply, the program  
message is discarded and an error is generated. Errors are reported using the  
IEEE Std. 488.2 status reporting model. A Query program message always ends  
with a question mark. Most queries return a reply within 200 ms except:  
“PR?”, “PRR?”, “SR?”, “ATM?”, “RATE?”: Up to 2 seconds.  
“RPT”, “ARANGE”, “AUTOZERO RUN”: Up to 3 seconds  
The syntax for using a QUERY program message is listed next to the keyword  
“Query:” in each program message summary in Section 4.4.4. Please note that  
queries in enhanced mode via the IEEE-488 port that results in an error will not  
result in a reply. You must check the error queue (use the “ERR” querie) to see  
if an error has occurred.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 84  
4. REMOTE OPERATION  
4.4  
COMMANDS  
4.4.1  
PROGRAMMING MESSAGES  
Some commands accept an optional suffix. This suffix can be used to specify the explicit Q-RPT  
to address. In most cases, each Q-RPT in the RPM4 operates as an independent  
measurement device. If the suffix is not specified, then the “Active” Q-RPT is assumed.  
The “RANGE” or “ARANGE” command can be used to select the “Active” Q-RPT. There are  
some limitations to use of the suffix when the RPM4 is in differential mode (see Section  
3.3.3.1) or the “HL” Q-RPT is active (see Section 3.2.4). See the program message  
descriptions for suffix use with a specific command.  
Table 16. Program Message List  
COMMAND  
DESCRIPTION  
n’ indicates an  
optional suffix  
Send a command string out of the RPM4 COM2 port.  
Stop pending operations  
Read or set a new AutoRange to use.  
Read the current atmospheric pressure (on-board barometer).  
Read or set the status of the AutoZ automatic zeroing function.  
Run AutoZero.  
Read or set the on-board barometer calibration  
Read or set the configuration of the COM1 port.  
Read or set the configuration of the COM2 port.  
Enable continuous measurements  
#
ABORT  
ARANGEn  
ATM  
AUTOZEROn  
AUTOZEROn=RUN  
CALAMB  
COM1  
COM2  
CONTn  
DATE  
Read or set the current date.  
Read the last error message.  
ERR  
Read or set the GPIB interface address.  
GPIB  
Read or set the fluid head settings.  
HEAD  
Read or set the RPM4 alphanumeric asset ID tag.  
Selects “classic” program message format  
ID  
L2  
Selects “enhanced” program message format  
Read or set the lower limit for the current range (negative gauge and differential  
modes only).  
L3  
LLn  
Return control to the RPM4 front panel.  
Read the power-up memory test status.  
LOCAL  
MEM  
Read or change the active measurement mode.  
Read or set the type of program message format to use.  
Read or set the status of low vent valve (Gxxx or BGxxx Q-RPT only)  
Read or set the user Lo Q-RPT calibration information.  
Read or set the user Lo Q-RPT calibration information (old command).  
Read the next RPM4 pressure.  
MMODEn  
MSGFMT  
NVENTn  
PCALn  
PCAL:XX  
PRn  
Read the next RPM4 pressure, rate, and ATM.  
Read the last RPM4 pressure, rate and ATM.  
Select a Q-RPT to be “active” in it’s default full scale range  
Read the next available rate of change of pressure.  
Read or set the Q-RPT measurement read rate and mode  
Read or set a flag that is cleared by a Not Ready condition.  
Enable remote local lockout operation.  
Read or set the pressure display resolution for the current Q-RPT and range.  
Reset the RPM4 to default user parameters.  
Read the available Q-RPT data.  
PRRn  
QPRRn  
RANGE  
RATEn  
READRATEn  
READYCKn  
REMOTE  
RESn  
RESET  
RPTn  
Read or set the front panel screen saver period.  
Read or set the SDS state for a specific Q-RPT  
Read or set the active Q-RPT SDS state  
Read or set the SDS mode for a specific Q-RPT  
Read the serial number of the RPM4.  
SCRSAV  
SDSn  
SDSACT  
SDSAUTOn  
SN  
Read the next available pressure status (Ready/Not Ready).  
Read or set the stability required for a Ready condition.  
Read or set the stability required for a Ready condition (% span/ s).  
Read or set the current time of day.  
SRn  
SSn  
SS%n  
TIME  
Convert a pressure in Pascal to pressure in the current units.  
Read or set the user defined pressure unit.  
UCOEFn  
UDU  
Page 85  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
COMMAND  
DESCRIPTION  
n’ indicates an  
optional suffix  
Read or set the upper limit for the current range.  
ULn  
Read or set the pressure unit of measure for the current range.  
Read the RPM4 software version.  
UNITn  
VER  
Read or set the AutoZero Zoffset for the specified Q-RPT.  
Read or set the AutoZ Zoffset for the specified Q-RPT (old command).  
ZOFFSETn  
ZOFFSET:XX  
4.4.2  
ERROR MESSAGESS  
Table 17. Error #s and Descriptions  
REPLY  
DESCRIPTION  
ERR# 0  
ERR# 2  
“OK”  
“Text argument is too long”  
“Arguments cannot be 0”  
“External device not detected”  
Not used  
ERR# 3  
ERR# 4  
ERR# 5  
ERR# 6  
“Numeric argument missing or out of range”  
“Missing or improper command argument(s)”  
“External device time-out error”  
“Unknown command”  
ERR# 7  
ERR# 8  
ERR# 9  
ERR# 10  
ERR# 11  
ERR# 12  
ERR# 13  
ERR# 14  
ERR# 17  
ERR# 18  
ERR# 19  
ERR# 20  
ERR# 21  
ERR# 22  
ERR# 23  
ERR# 25  
ERR# 26  
ERR# 27  
ERR# 28  
ERR# 29  
ERR# 30  
ERR# 31  
ERR# 32  
ERR# 37  
ERR# 38  
ERR# 39  
ERR# 45  
ERR #46  
ERR #52  
ERR# 53  
“Missing or invalid command suffix”  
“Command missing argument”  
“System overpressured” or “overpressure may result”  
“Text queue overflow”  
“User unit not defined”  
Not used  
“Command not yet available”  
“Not available with absolute units”  
“Not available with gauge device”  
Not used  
“Pressure is not stable”  
“Option not available or installed”  
Not used  
“COM port failed to initialize”  
“Internal device failure”  
“Device failure”  
“Device not available”  
“Must be on range HI”  
“Exceeds upper or lower limit”  
“Not stable enough”  
“Data table is full”  
“Selected range is not available”  
“Data verify error”  
“Argument not allowed”  
“Argument cannot be negative”  
“Command obsolete”  
“Not Available”  
© 2004-2007 DH Instruments, a Fluke Company  
Page 86  
4. REMOTE OPERATION  
4.4.3  
PROGRAM MESSAGE DESCRIPTION OVERVIEW  
Each program message description is separated into the following sections:  
Purpose  
A brief description of the programs message’s function.  
Command  
This is the Enhanced program message syntax to send data to the RPM4 or to execute an  
RPM4 function. The RPM4 must be set to use the enhanced format (see Section 3.5.2.3)  
to use the syntax and style shown. It may be sent alone, or followed by at least one white  
space and additional argument(s) to show that arguments can be passed. If there are  
multiple arguments, then commas must separate them. If you are using the IEEE-488 port,  
multiple command type program messages can be sent in one message if you separate  
them with a semicolon. There will be no reply from the RPM4 using the IEEE-488 port  
unless the command is immediately followed by the query operator “?”. If you are using  
the COM1 port, the PPC1 will reply and you must wait for this reply. If this field is not  
listed in the program message description, then the Command type is not supported when  
using the Enhanced format.  
Query  
This is the Enhanced program message syntax to request data from the RPM4. The RPM4  
must be set to use the enhanced format (see Section 3.5.2.3). The RPM4 will always  
reply to a query. You must wait for this reply before issuing another program message. If  
this field (Query) is not listed in the program message description, then the Query type for  
the program message is not supported when using the Enhanced format.  
This is the Classic program message syntax to send data to the RPM4, to execute an  
RPM4 function, or to query for data. The RPM4 must be set to use the classic format  
(see Section 3.5.2.3). The command may be followed by a ‘(=)’ and additional argument  
characters to show that argument(s) can be passed. If there are multiple arguments, then  
commas must separate them. The RPM4 will always reply to a Classic program message.  
You must wait for this reply before issuing another program message. If this field is not listed  
in the program message description, then it is not supported when using the classic  
format.  
Classic  
Suffix  
Some commands support an optional suffix. This suffix is used to specify a Q-RPT to which  
the command applies, since many settings are Q-RPT specific:  
Suffix of ‘1’ for Hi Q-RPT access  
Suffix of ‘2’ for Lo Q-RPT access  
Suffix of ‘3’ for HL Q-RPT access.  
If an optional suffix is allowed but not given, then the “Active Q-RPT” will be addressed. The  
“Active Q-RPT” is the Q-RPT that is currently displayed on the top line of the front panel of the  
RPM4, and is identified by the text label in the upper right of the pressure display screen. The  
last Q-RPT ranged or selected using the “RANGE” or “ARANGE” commands is the “Active” Q-  
RPT. The “ARANGE”, “RANGE” or “RPT” command query can be used to determine which  
Q-RPT is currently active. With the Hi Q-RPT In differential mode of operation, there are some  
limitations on access to the Lo Q-RPT, and with the HL Q-RPT there are limitations on access  
to both the Hi and the Lo Q-RPTs independently.  
Arguments  
Default  
If the program message can be used to set data inside the RPM4, then this section describes  
the arguments and their limits.  
If the program message can be used to set data inside the RPM4, then this line shows  
(using the enhanced format) the default setting from the factory.  
Remarks  
Example  
This field has the details and remarks about the command.  
Examples are given for the enhanced and classic methods.  
Enhanced:  
An example of the use of an enhanced format program message to be  
sent to the RPM4 is shown. The message sent to the RPM4 appears after  
the “Cmd sent:” label. If only a Query type exists, the “Query sent:”  
label is shown instead. Directly under this label, “Query reply” shows a  
typical reply to a query type. “Reply:” shows that a query format does  
not exist. It may have a short description next to it.  
Classic:  
An example of the use of a classic program message to be sent to the  
RPM4 is shown. The command sent to the RPM4 appears after the  
“Cmd sent:” label. The “Reply” label shows a typical reply to the  
“Sent” example. It may have a short description next to it.  
Errors  
If the program message can report an argument error, the types of errors are listed.  
If using the classic format or the COM1 port, the error message is replied after receiving  
the program message. If using the enhanced format via the IEEE-488 port, the error  
condition is handled by the status reporting model which stores the errors in an Error  
Queue and can be programmed to assert the IEEE-488 SRQ line to signal an error has  
occurred. In either case, the “ERR” or “ERR?” program message can be used to  
retrieve a text description of the error.  
See Also  
Indicates related commands (“----“) and refers to manual sections giving detail on RPM4  
operation corresponding to the program message.  
Page 87  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
4.4.4  
PROGRAM MESSAGE DESCRIPTIONS  
#
Purpose  
Classic  
Arguments  
To allow the host PC to communicate with a device connected to the RPM4 COM2 port.  
“#xx”  
xx:  
The string to send out of the RPM4 COM2 port. It must be less than  
40 characters long.  
Remarks  
The RPM4 COM2 port can be used to communicate to another RS232 device (such as  
another RPM4). This allows the user to use a single COM port or IEEE-488 port on the  
host computer to communicate with the RPM4 and another RS232 device. A carriage  
return and a line feed (<CR><LF>) are added to the string.  
After this program message is issued, the RPM4 will reply back every string received by  
the RPM4 COM2 port that is terminated with a carriage return. Line feeds are discarded.  
This will discontinue when the next query is sent to the RPM4.  
There is no other reply from this program message. Prior to using this program message,  
you must ensure that the RPM4 COM2 port is correctly set up to communicate with the  
device on COM2. Refer to the “COM2=“ program message.  
Example  
(classic)  
Sent:  
Reply:  
“#VER”  
“DH INSTRUMENTS, INC RPM4 us A1000/A0015 Ver2.00 ”  
This example assumes that a second RPM4’s COM1 port is connected to the RPM4  
COM2 port. This example gets the version of the second RPM4.  
See Also  
“COM2”  
3.5.2  
ABORT  
Purpose  
Cancels any pending data requests by the “PR”, “PRR” “RATE”, “SR” or “CONT”  
commands.  
Command  
Classic  
“ABORT”  
“ABORT”  
Remarks  
Example  
(enhanced)  
Example  
(classic)  
See Also  
This program message is usually used to ensure the RPM4 is in an idle condition.  
Cmd sent:  
Reply:  
“ABORT”  
“ABORT” (no reply if IEEE-488)  
Sent:  
“ABORT”  
Reply:  
“ABORT”  
“PR”, “PRR” “RATE”, “SR” or “CONT”  
3.2.1  
© 2004-2007 DH Instruments, a Fluke Company  
Page 88  
4. REMOTE OPERATION  
ARANGEn  
Purpose  
Command  
Read or set a new AutoRange range to use.  
“ARANGEn Range, unit, mode (,RptLabel)” (set to user defined range)  
“ARANGE Q-RPTLabel”  
(set to Q-RPT default range)  
Query  
“ARANGEn?”  
Classic  
“ARANGEn= Range, units, mode (,RptLabel)” (set to user defined range)  
“ARANGE= Q-RPTLabel”  
(set to Q-RPT default range)  
Query  
“ARANGEn”  
Optional Suffix  
“n”  
A suffix may be used instead of “RptLabel”  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT  
Arguments  
Range:  
Unit:  
Mode:  
The AutoRange maximum pressure. Cannot be negative.  
The unit of measure of the Range argument.  
The measurement mode of the Range argument:  
“A” for absolute  
“G” for gauge  
“N” for negative gauge  
Measured pressure values are returned with “g” to identify measurement  
mode for both gauge and negative gauge measurement modes.  
RptLabel:  
(optional)  
One of the Q-RPTs that is available.  
“IH”: Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF. HL Q-RPT if  
the Hi and Lo Q-RPTs are OFF.  
“IL”: Lo Q-RPT  
“HL”: HL Q-RPT.  
Remarks  
The ARANGE command is used to define an RPM4 range by specifying a desired unit of  
measure, measurement mode and maximum pressure, and have the RPM4 pick the best  
available Q-RPT and make adjustments to optimize operation in that range.  
The optional suffix or the “RptLabel” argument can be used to specify which Q-RPT you  
wish to use for the AutoRange range instead of allowing the RPM4 to pick the best Q-  
RPT. By using this option you can override the internal logic that picks the most suitable Q-  
Q-RPT. This Q-RPT specified must be valid for the maximum pressure and measurement  
mode specified.  
The reply indicates the current range data, including the Q-RPTLabel used for the range.  
If “inWa” is specified for the unit, the temperature reference can be given after the unit  
text (“inWa4”, “inWa20” or “inWa60” corresponding to inWa at 4 °C, 20 °C or 60 °F). If no  
number is given, a default of 20 °C is assumed. There is no indication of the temperature  
reference in the reply.  
If you just specify the Q-RPTLabel without any other arguments, the Q-RPT specified will  
become active in it’s last range and settings. The previously set unit and measurement  
mode for the Q-RPT specified will become active.  
Example  
(enhanced)  
Example  
(classic)  
Example  
(enhanced)  
Example  
(classic)  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Cmd sent:  
“ARANGE?”  
“100.00, psi, A, IH”  
“ARANGE”  
“100.00, psi, A, IH”  
(read the current range in the current units)  
(read the current range in the current units)  
“ARANGE? 250, inWa4, G (range of 250 inWa @ 4 °C in gauge mode)  
“250.00 inWa, G, IH”  
“ARANGE=500, kPa, G  
“500.00 kPa, G, IL”  
(Lo Q-RPT is used)  
(range of 500 kPa in gauge mode)  
(Lo Q-RPT is used)  
(range of 50 psi in absolute mode on  
the Lo Q-RPT)  
Example  
(enhanced)  
“ARANGE2 50, psi, A  
Query reply:  
Cmd sent:  
“50.000 psi, A, IL”  
“ARANGE IH  
“500.000 kPa, A, IH”  
(No reply if GPIB-488)  
(Hi Q-RPT’s prev range made active)  
(No reply if GPIB-488)  
Example  
(enhanced)  
Query reply:  
ERR# 6:  
ERR#10:  
Errors  
Range“ maximum pressure exceeds available Q-RPTs or is negative.  
RPT specified by the optional suffix is not valid for the current operating  
conditions  
ERR# 19:  
ERR# 20:  
ERR# 29:  
ERR# 53:  
Cannot Range to ‘0’ with absolute units.  
Cannot Range to ‘0’ with gauge units.  
Correct type of Q-RPT for the selected “Mode” is not available.  
RPT specified is not available.  
See Also  
“RPT”, “RANGE”, “MMODE”, “UNIT”  
3.3.4, .3.2.4, 3.3.3, 3.3.2  
Page 89  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
ATM  
Purpose  
Reads the next measured pressure from RPM4’s on-board barometer (if present).  
Query  
“ATM?”  
Classic  
Remarks  
“ATM”  
The atmospheric pressure as measured by the RPM4 on-board barometer is returned in  
the current pressure units of the active Q-RPT (always absolute). This measurement is  
followed by the units text. Not all RPM4s are equipped with an on-board barometer.  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Query sent:  
Query reply:  
Sent:  
Reply:  
ERR# 23:  
3.5.7.1  
“ATM?”  
“97.12348 kPa a”  
“ATM”  
“97.12384 kPa a”  
RPM4 is not equipped with a barometer.  
See Also  
AUTOZEROn  
Purpose  
Command  
Query  
Read or set the status of the AutoZ function.  
“AUTOZEROn state”  
“AUTOZEROn?”  
Classic  
“AUTOZEROn= state”  
“AUTOZEROn”  
Default  
“AUTOZERO1”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Arguments  
Remarks  
‘state’:  
’0’ Autozero OFF  
’1’ Autozero ON  
The RPM4 AutoZ function can be turned ON and OFF. There is a separate AutoZ flag for  
the gauge, absolute, and differential measurement modes for each Q-RPT. This  
command sets the AutoZ status for the current mode of the specified or the active Q-RPT  
only. To set the sate of AutoZ for a measurement mode, you must be in that mode.  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Sent:  
Query reply:  
ERR# 7:  
“AUTOZERO 0”  
“0”  
“AUTOZERO=0”  
“AUTOZERO=0”  
The argument was other than ‘0’ or ‘1’.  
The suffix is invalid.  
(No reply if GPIB-488)  
ERR# 10:  
See Also  
“ZOFFSET”, “MMODE”  
3.5.1  
AUTOZEROn=RUN  
Purpose  
Command  
Query  
Run the AutoZero routine.  
“AUTOZEROn RUN (,Pref)”  
“AUTOZEROn? RUN (,Pref)”  
“AUTOZEROn= RUN (,Pref)”  
Classic  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
The AutoZ reference pressure in Pa. Optional when the RPM4 is not in  
absolute measurement mode, as the reference is usually “0”.  
Arguments  
Remarks  
‘Pref’:  
The RPM4 AutoZ function can be remotely run with this command only if AutoZero is  
ON. You should ensure that the pressure is stable for valid determination of Zoffset. If in  
differential mode, the previous 5 measurements of the Q-RPTs are averaged for Zoffset  
calculation so you should ensure that the RPM4 has been stable for at least 5  
measurement cycles before running a remote AutoZ in differential mode.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
“AUTOZERO RUN”  
“OK”  
(No reply if GPIB-488)  
“AUTOZERO? RUN, 97283”  
“OK”  
“AUTOZERO=RUN”  
“OK”  
An argument was not given for the AutoZ reference in absolute mode.  
(abs AutoZero to 97283 Paa)  
Query reply:  
ERR# 6:  
ERR# 10:  
ERR# 53  
Invalid suffix  
AutoZero is currently OFF.  
See Also  
“ZOFFSET”, “MMODE”, “AUTOZERO”  
3.5.1  
© 2004-2007 DH Instruments, a Fluke Company  
Page 90  
4. REMOTE OPERATION  
CALAMB  
Purpose  
Command  
Query  
Read or set the on-board barometer calibration.  
“CALAMB adder, mult, CalDate”  
“CALAMB?”  
Classic  
“CALAMB=adder, mult, CalDate”  
“CALAMB”  
Defaults  
“CALAMB = 0.0, 1.0, 19800101”  
Arguments  
Adder:  
Mult:  
CalDate:  
The Barometer calibration adder (PA), in Pascal.  
The Barometer calibration multiplier (PM) from 0.1 to 100.  
The date of the calibration in the format “YYYYMMDD”  
Remarks  
The barometer calibration information can be accessed with this program message. Using this  
program message overwrites the current calibration coefficients, so caution must be used.  
Changes made take effect immediately.  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Sent:  
Reply:  
ERR# 6:  
3.5.7.1, 5.3  
“CALAMB? 2.1, 1.000021, 20011201”  
2.10, 1.000021, 20011201”  
“CALAMB=2.1, 1.000021, 20011201”  
2.10, 1.000021, 20011201”  
One of the arguments is out of range.  
See Also  
COM1  
Purpose  
Command  
Query  
Read or set the RS232 settings for the COM1 port.  
“COM1 baud, parity, data, stop”  
“COM1?”  
Classic  
“COM1=baud, parity, data, stop”  
“COM1”  
Arguments  
Baud:  
Parity:  
Data:  
Stop:  
The baud rate. This may be ‘300’, ‘600’,’1200’,’2400’,’4800’, ‘9600’ or ‘19200’.  
The data parity. This may be ‘O’ for odd, ‘E’ for even, or ‘N’ for none.  
The number of data bits. This may be ‘7’ or ‘8’.  
The number of stop bits. This may be ‘1’ or ‘2’.  
Defaults  
Remarks  
“COM1 2400,E,7,1”  
The COM1 port is used to communicate to the RPM4. When the COM1 port configuration of the  
RPM4 is changed, the program message reply (COM1 use only) is sent at the old COM1 settings,  
but all subsequent communications are accomplished at the new COM1 settings.  
A 250ms or longer delay after receiving the reply to this command will ensure that the RPM4 has  
changed the COM port settings and is ready for communications at the new settings.  
Example  
(enhanced)  
Cmd sent:  
Query reply:  
“COM1 9600,N,8,1”  
“9600,N,8,1” (No reply if GPIB-488)  
Example  
(enhanced)  
Cmd sent:  
Query reply:  
“COM1? 9600,N,8,1”  
“9600,N,8,1”  
Example  
(classic))  
Sent:  
Reply:  
“COM1=9600,N,8,1”  
“9600,N,8,1”  
Errors  
See Also  
ERR# 7:  
“COM2”  
3.5.2.1  
Missing or improper program message argument(s).  
COM2  
Purpose  
Command  
Query  
Read or set the RS232 settings for the COM2 port.  
“COM2 baud,parity,data,stop”  
“COM2?”  
Classic  
“COM2= baud,parity,data,stop”  
“COM2”  
Arguments  
baud:  
parity:  
Data:  
stop:  
The baud rate. This may be ‘300’, ‘600’,’1200’,’2400’,’4800’, ‘9600’ or ‘19200’.  
The data parity. This may be ‘O’ for odd, ‘E’ for even, or ‘N’ for none.  
The number of data bits. This may be ‘7’ or ‘8’.  
The number of stop bits. This may be ‘1’ or ‘2’.  
Defaults  
Remarks  
“COM2 2400,E,7,1”  
COM2 is generally used to allow the host computer to communicate through the RPM4 to an  
additional device connected to COM2. This can be useful if the host computer does not have 2  
serial ports available.  
Example  
(enhanced)  
Cmd sent:  
Query reply:  
“COM2 9600,N,8,1”  
“9600,N,8,1”  
(No reply if GPIB-488)  
Example  
Cmd sent:  
“COM2? 9600,N,8,1”  
(enhanced)  
Query reply:  
“9600,N,8,1”  
Example  
(classic)  
Sent:  
Reply:  
“COM2=9600,N,8,1”  
“9600,N,8,1”  
Errors  
ERR# 7:  
Missing or improper program message argument(s).  
See Also  
“COM1”  
3.5.2.1  
Page 91  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
CONTn  
Purpose  
Query  
Have the RPM4 reply continuously as each new measurement becomes available.  
“CONTn?”  
Classic  
“CONTn”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Remarks  
This command is somewhat different than most as it enables the RPM4 to continuously output the  
selected Q-RPT’s measurement without further queries. This continues until the next query is  
received by the RPM4, or if the ABORT” or “*CLS” command is received. The frequency of the  
measurements is determined by the readrate of the Q-RPT. The data returned includes the  
pressure of the specified or active Q-RPT, current unit of measure and measurement mode.  
Example  
(enhanced)  
Example  
(classic)  
Query sent:  
Query reply:  
Query sent:  
Reply:  
“CONT1?”  
“1936.72 kPa a” (repeats every measurement cycle)  
“CONT”  
“1936.72 kPa a” (repeats every measurement cycle)  
See Also  
“PR”, “READRATE”  
DATE  
Purpose  
Command  
Query  
Read or set the RPM4 date.  
“DATE date”  
“DATE?”  
Classic  
“DATE= date”  
“DATE”  
Arguments  
Remarks  
date:  
The date in the numerical only format “YYYYMMDD”  
The RPM4 has an internal real time calendar clock. The span of acceptable dates ranges  
from 19800101 to 20791231. The reply is always in the YYYYMMDD format.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
Reply:  
ERR# 6:  
“TIME”  
“DATE 20030115”  
“20030105”  
“DATE? 20030105”  
“20030105”  
“DATE=20021201”  
“20021201”  
Missing or improper program message argument(s).  
(No reply if GPIB-488)  
See Also  
3.5.5.3  
ERR  
Purpose  
Query  
Read the new available error message from the Error Queue.  
“ERR?”  
Classic  
Remarks  
“ERR”  
This program message obtains additional details about an error that has occurred. If the user  
receives an “ERR# nn” reply, or the enhanced mode is enabled using the IEEE-488 interface and  
an error has been detected, the error is put into a FIFO Error Queue. The “ERR” program  
message pulls and replies the oldest error message available. In “classic” mode only the most recent  
error can reside in the queue. “OK” is replied if there are no error messages left. If an error occurs in  
enhanced mode using the IEEE-488 interface, no reply is generated even if the command was a  
query.  
Example  
(enhanced):  
Example  
(classic)  
Query sent:  
Query reply:  
Sent:  
“ERR?”  
“Numeric argument missing or out of range”  
“ERR”  
“Numeric argument missing or out of range”  
Reply:  
See Also  
4.4.2  
© 2004-2007 DH Instruments, a Fluke Company  
Page 92  
4. REMOTE OPERATION  
GPIB  
Purpose  
Command  
Query  
Read or set the GPIB interface address.  
“GPIB addr”  
“GPIB?”  
Classic  
“GPIB=addr”  
“GPIB”  
Defaults  
“GPIB 10”  
Arguments  
Remarks  
Addr:  
The address of the IEEE-488 (GPIB) interface (1 to 30)  
The GPIB address is changed following the reply of this command. Each device on a GPIB  
interface bus requires a unique address.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Cmd sent:  
Query reply  
Cmd sent:  
Query reply  
Sent:  
“GPIB 21”  
“21”  
“GPIB? 21”  
“21”  
“GPIB=21”  
“21”  
(No reply if GPIB-488)  
Reply:  
Errors  
See Also:  
ERR# 6:  
3.5.2.2  
The argument is not within given limits.  
HEAD  
Purpose  
Command  
Query  
Read or set the fluid head settings.  
“HEAD height, units, fluid”  
“HEAD?”  
Classic  
“HEAD=height, units, fluid”  
“HEAD”  
Defaults  
“HEAD 0, cm, N2”  
Arguments  
height:  
The height of the test in relation to the RPM4. The value is positive if the test is  
above the RPM4, or negative if below the RPM4. The value can be between -  
9999 and 9999. Setting the value to ‘0’ disables the head correction.  
The height units. This must be “in” or “cm”.  
units:  
gas:  
The fluid type. This must be “N2”, “Air”, “He”, “Oil”, “H2O”, or “User”.  
Remarks  
The RPM4 can make a fluid head correction to allow it to display the pressure at a level other than  
the reference level of the RPM4.  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Sent:  
“HEAD? 10,in,N2”  
“10, in, N2”  
“HEAD=10,in,N2”  
“10, in, N2”  
The fluid text is too long  
The height is not within given limits or the unit is invalid.  
The fluid text is invalid  
Reply:  
ERR# 2:  
ERR# 6:  
ERR #7:  
3.3.7, 3.5.3  
See Also:  
ID  
Purpose  
Command  
Query  
Read or set the user defined instrument identification label.  
“ID string”  
“ID”  
Classic  
“ID=string”  
“ID”  
Arguments  
Remarks  
String:  
An alphanumeric string up to 12 characters long.  
The user defined ID label can be used to allow the user to “tag” the RPM4 with a unique  
identifier. This ID is stored in non-volatile memory and cannot be erased by a power failure,  
system fault or reset. The ID should not be changed frequently, as the non-volatile memory  
may fail after 100,000 write operations.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply  
Cmd sent:  
Query reply  
Sent:  
“ID RPM4 #A01”  
“RPM4 #A01”  
“ID? RPM4 #A01”  
“RPM4 #A01”  
“ID=RPM4 #A01”  
“RPM4 #A01”  
Text argument is too long (more than 12 characters)  
(No reply if GPIB-488)  
Reply:  
ERR# 2  
See Also  
3.5.5.4  
Page 93  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
L2 / L3  
Purpose  
Read or set the type of program command format to use (classic or enhanced).  
Command  
“L2”enables “classic” mode  
“L3”enables “enhanced” mode  
Defaults  
Remarks  
“L2”  
(Classic mode)  
The user can select the type of remote command format using these simplified commands.  
There is no query format. This format must agree with the format sent to the RPM4. This  
command is a replacement for the “MSGFMT” command.  
Example  
(enhanced)  
Example  
(classic)  
Cmd sent:  
Query reply:  
Sent:  
“L3”  
“L3”  
“L2”  
“L2”  
(No reply if IEEE-488)  
Reply:  
See Also  
“MSGFMT”  
4.3, 3.5.2.3  
LLn  
Purpose  
Read or set the lower pressure limit for the active range and measurement mode (negative  
gauge or differential measurement mode only).  
Command  
Classic  
“LLn limit”  
“LLn =limit”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF and the HL  
Q-RPT is not active.  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT if the HL Q-RPT is not active and measurement  
mode is not differential.  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active.  
Arguments  
Remarks  
"limit:  
The lower pressure limit for the current pressure range in the specified Q-  
RPT’s current unit of measure unit and measurement mode. Value is always  
a negative value of gauge pressure.  
Negative gauge and differential modes in RPM4 have a lower limit. If the pressure is less  
than the lower limit, the pressure display flashes. This feature should always be used to  
prevent accidental over (under) pressure of a device under test.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Reply:  
Cmd sent:  
Reply:  
Sent:  
Reply:  
ERR# 6:  
ERR# 10  
ERR# 23  
“UL”, “MMODE”  
3.4.4, 3.3.3  
“LL -4”  
“-4 kPa g”  
“LL? -4”  
“-4 kPa g”  
“LL=-4”  
“-4 kPa g”  
The limit argument is invalid.  
(no reply if IEEE-488)  
The suffix is invalid  
The mode must be negative gauge to specify a lower limit.  
See Also  
LOCAL  
Purpose  
Command  
Classic  
Returns control to the RPM4 front panel.  
“LOCAL”  
“LOCAL”  
Remark  
The REMOTE program message can lock the front panel out completely. The user can return  
to local operation by sending the LOCAL program message, sending the IEEE-488 ‘GTL’  
command (if in enhanced format), or by cycling RPM4 power.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Cmd sent:  
Reply:  
Cmd sent:  
Reply:  
Sent:  
Reply:  
“LOCAL”  
“LOCAL”  
“LOCAL?”  
“LOCAL”  
“LOCAL”  
“LOCAL”  
(no reply if IEEE-488)  
See Also  
“REMOTE”  
© 2004-2007 DH Instruments, a Fluke Company  
Page 94  
4. REMOTE OPERATION  
MEM  
Purpose  
Query  
Classic  
Remarks  
Read the status from the power-up memory test.  
“MEM?”  
“MEM”  
The RPM4 system memory stores the user settings (units, resolution) and retains them when  
the unit is OFF. On power-up, this memory is checked. If this memory is corrupted, all user  
settings are reset to default , and the MEM status is set to reflect this.  
Example  
(enhanced)  
Query sent:  
Reply:  
“MEM?”  
“0” RPM4 data corrupted and was set to factory defaults.  
“1” The memory was found to be OK on power-up.  
“MEM”  
“MEM=0” RPM4 data corrupted and was set to factory defaults.  
“MEM=1” The memory was found to be OK on power-up.  
Example  
(classic)  
Sent:  
Reply:  
See Also  
3.5.9, 3.5.7.5  
MMODEn  
Purpose  
Command  
Query  
Read or change the active measurement mode.  
“MMODEn mode”  
“MMODEn?”  
Classic  
“MMODEn=mode”  
“MMODEn ”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF and the HL  
Q-RPT is not active.  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT if the HL Q-RPT is not active and measurement  
mode is not differential.  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active.  
Arguments  
Mode:  
"A"  
"G"  
"N"  
“D”  
Absolute mode  
Gauge mode  
Negative gauge mode  
Differential mode (available only for the Hi Q-RPT)  
Measured pressure values are returned with “g” to identify measurement  
mode for both gauge and negative gauge measurement modes. Differential  
mode restricts access to settings on the Lo Q-RPT.  
Remarks  
The measurement mode can also be set using the “UNIT” command but the “UNIT” command  
does not distinguish between gauge and negative gauge in it’s reply, while the “MMODE”  
does. Measurement mode is range specific.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(enhanced)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
ERR# 6:  
“MMODE A”  
“A”  
“MMODE? A”  
“A”  
“MMODE=G”  
“G”  
Invalid argument text.  
(No reply if IEEE-488)  
ERR# 7:  
ERR#10:  
ERR# 20:  
Abs mode only with altitude units or gauge mode only with gauge Q-RPT.  
The suffix indicating the Q-RPT is invalid for the current conditions.  
Absolute or negative gauge mode not available with gauge Q-RPT.  
Absolute Q-RPT with an absolute and negative gauge OFF calibration.  
The current range cannot support gauge mode.  
ERR# 53:  
Gauge mode range would be negative.  
Lo Q-RPT not suitable for differential mode.  
See Also  
“UNIT”, “ARANGE”  
3.3.3  
Page 95  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
MSGFMT  
Purpose  
Command  
Query  
Read or set the type of program command format to use (enhanced or classic).  
“MSGFMT mode  
“MSGFMT?”  
Classic  
“MSGFMT= mode  
“MSGFMT”  
Arguments  
mode:  
‘1’ to use the enhanced command format.  
‘0’ to use the classic command format.  
Defaults  
Remarks  
“MSGFMT 0”  
The user can select the type of remote command format to use. This format must agree with the  
format sent to the RPM4  
The enhanced query form of this command (“MSGFMT? n”) should always be used to set the  
desired format, as it will be accepted regardless of the current format (classic or enhanced).  
It is recommended to use the “L2” and “L3” commands instead of this command for new designs.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
“MSGFMT 1”  
“1”  
“MSGFMT? 1”  
“1”  
“MSGFMT=1”  
“MSGFMT=1”  
Missing or improper program message argument(s).  
(No reply if IEEE-488)  
Reply:  
ERR# 6:  
See Also  
“L2 / L3”  
4.3, 3.5.2.3  
NVENTn  
Purpose  
Command  
Query  
Read or set the status of low (negative) vent valve (Gxxx or BGxxx Q-RPT only)  
“NVENTn mode”  
“NVENTn?”  
Classic  
“NVENTn= mode”  
“NVENTn”  
Default  
“NVENTn AUTO”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given. The “Hi” Q-RPT is assumed if the  
HL Q-RPT is active and no suffix is given.  
‘1’ Specify the Hi Q-RPT  
‘2’ Specify the Lo Q-RPT  
Arguments  
Remarks  
Mode:  
’0’ to close the low vent valve.  
’1’ to open the low vent valve.  
‘AUTO’ for the RPM4 to automatically open and close the low vent valve.  
Gxxx or BGxxx Q-RPTs each have a low vent valve that is used to vent the TEST(-) port.  
This valve is normally controlled automatically depending on current RPM4 operation but it can  
be commanded to open or close using the “NVENT” command.  
The reply includes two fields. The first indicates the low vent status. The second indicates  
whether the low vent function is AUTO or MANUAL  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
“NVENT? 0”  
“0, MANUAL”  
“NVENT? AUTO”  
“1, AUTO”  
“NVENT=1”  
“0, MANUAL”  
Query reply:  
See Also  
3.5.7.4  
© 2004-2007 DH Instruments, a Fluke Company  
Page 96  
4. REMOTE OPERATION  
PCALn  
Purpose  
Command  
Query  
Read or set the calibration information for the Hi or Lo Q-RPT.  
“PCALn adder, mult, CalDate”  
“PCALn?”  
Classic  
“PCALn= adder, mult, CalDate”  
“PCALn”  
Defaults  
“PCALn = 0.0, 1.0, 19800101”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given. The Hi Q-RPT is assumed if the HL  
Q-RPT is active and no suffix is given.  
‘1’ Specify the Hi Q-RPT  
‘2’ Specify the Lo Q-RPT  
Arguments  
Remarks  
Adder:  
Mult:  
CalDate:  
The Q-RPT calibration adder (PA). In Pascal.  
The Q-RPT calibration multiplier (PM) from 0.1 to 100.  
The date of the calibration in the format “YYYYMMDD” by default. Any other  
format up to 8 characters long is also accepted, and the replied format is in th  
previously entered format.  
The user defined pressure calibration information for the specified Q-RPT (Hi or Lo) can be  
accessed with this program message. The HL Q-RPT does not have it’s own calibration  
information. Using this program message overwrites the current calibration coefficients, so caution  
must be used. Changes made using this program message take effect immediately.  
For compatibility with the obsolete style PPC3 “PCAL:HI” and “PCAL:LO” commands, “:HI” and  
“:LO” can be used in place of the suffix “n” but this is not recommended for new applications.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
“PCAL2? 2.1, 1.000021, 20011201”  
2.10 Pa, 1.000021, 20011201” (No reply if GPIB-488)  
“PCAL? 2.1, 1.000021, 20011201”  
2.10 Pa, 1.000021, 20011201”  
“PCAL:HI? 2.1, 1.000021, 20011201” (PPC3 style is OK)  
2.10 Pa, 1.000021, 20011201”  
“PCAL1=2.1, 1.000021, 20011201”  
“ 2.10 Pa, 1.000021, 20011201”  
Reply:  
Errors  
ERR# 6:  
ERR# 10:  
5.2  
One of the arguments is out of range.  
The suffix is invalid.  
See Also  
PRn  
Purpose  
Query  
Read the next available pressure measurement.  
“PRn?”  
Classic  
“PRn”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Remarks  
The next available pressure value for the specified or active Q-RPT is read in the current pressure  
units. The data returned also contains Ready/Not Ready information, and the pressure unit of  
measure and measurement mode.  
The reply field is always 20 characters long. The first 3 characters of the reply are reserved for the  
ready status. The ready status is described in the “SR” program message. The pressure value and  
pressure unit of measure are right justified in this field.  
After receiving this program message, the RPM4 replies back with the data after a new pressure  
measurement cycle is complete. This can take up to the current read rate period (1.2 seconds by  
default).  
Example  
(enhanced)  
Example  
(classic)  
Query sent:  
Query reply:  
Query sent:  
Reply:  
“PR?”  
“R  
“PR”  
“R  
1936.72 kPa a”  
1936.72 kPa a”  
See Also  
“PRR”, “QPRR”, “SR”, “ABORT”, “READRATE”  
3.1.1, 3.2.1, 3.5.7.2  
Page 97  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
PRR  
Purpose  
Read the next available Ready condition, pressure measurement, rate and on-board  
barometer reading.  
Query  
“PRR?”  
Classic  
“PRR”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Remarks  
The next available Ready condition, Q-RPT pressure measurement, rate of pressure change,  
and barometric pressure is replied in the current pressure unit of measure. . This can take up  
to the current read rate period (1.2 seconds by default). Each data field is separated by a  
comma, and is returned in the following order:  
ready, pressure UNITS, rate UNITS/s, atm UNITS  
Here are the field descriptions:  
ready:  
pressure:  
Three character ready status field. Refer to the “SR” command.  
The measured pressure for the active Q-RPT in the current pressure unit.  
This is followed by the current pressure unit.  
rate:  
atm:  
The measured rate of pressure change for the active Q-RPT in the current  
pressure unit per second. This is followed by the current pressure unit of measure.  
The pressure measured by the RPM4 on-board barometer in the current  
pressure unit (and always absolute). This is followed by the current pressure  
unit. Not all RPM4s are equipped with an on-board barometer. This field is  
missing if the RPM4 is not equipped with an on-board barometer.  
“PRR?”  
Example  
(enhanced)  
Query sent:  
Query reply:  
“R,2306.265 kPaa,0.011 kPa/s,97.000 kPa a”  
“R,2306.265 kPaa,0.011 kPa/s”  
(no barometer)  
Example  
(classic)  
See Also  
Query sent:  
Reply:  
“PR”, “QPRR”, “SR”  
3.1.1, 3.2.1, 3.5.7.1  
“PRR”  
“R,2306.265 kPaa,0.011 kPa/s,97.000 kPa a”  
QPRR  
Purpose  
Read the last Q-RPT pressure measurement, pressure rate and on-board barometer output  
immediately.  
“QPRR?”  
“QPRR”  
Query  
Classic  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Remarks  
The last measured Ready/Not Ready condition, active Q-RPT pressure measurement, rate of  
pressure change, and barometric pressure is replied in the current pressure unit of measure  
immediately. This program message is useful when a rapid response of measured pressure  
is needed. It does not result in quicker pressure measurements. Each data field is separated  
by a comma, and is returned in the following order:  
Ready, pressure UNITS, rate UNITS/s, atm UNITS  
Here are the field descriptions:  
ready:  
pressure:  
Three character ready status field. Refer to the “SR” command.  
The measured pressure for the selected Q-RPT in the current pressure unit.  
This is followed by the current pressure unit and measurement mode.  
The measured rate of pressure change for the active Q-RPT in the current  
unit of pressure per second. This is followed by the current pressure unit.  
The pressure measured by the RPM4 on-board barometer in the current  
pressure unit (but always absolute). This is followed by the current pressure  
unit. Not all RPM4s are equipped with an on-board barometer. This field is  
missing if the RPM4 is not equipped with a barometer.  
“QPRR?”  
rate:  
atm:  
Example  
(enhanced)  
Query sent:  
Query reply:  
“R,2306.265 kPa a,0.011 kPa/s,97.000 kPa a”  
“R,2306.265 kPa a,0.011 kPa/s” (no barometer)  
Example  
(classic)  
See Also  
Query sent:  
Reply:  
“PR”, “PRR”, “SR”  
“QPRR”  
“R,2306.265 kPa a,0.011 kPa/s,97.000 kPa a”  
3.1.1, 3.2.1, 3.5.7.1  
© 2004-2007 DH Instruments, a Fluke Company  
Page 98  
4. REMOTE OPERATION  
RANGE  
Purpose  
Change the active range to the default range of the Hi, Lo or HL Q-RPT. Replies the active  
range full scale, pressure unit and measurement mode.  
Command  
Query  
“RANGE Rng”  
“RANGE?”  
Classic  
“RANGE= Rng”  
“RANGE ”  
Default  
“RANGE IH”  
Rng:  
“IH” for the Hi Q-RPT  
“IL” for the Lo Q-RPT  
“HL” for the HL Q-RPT  
Remarks  
The active Q-RPT must be selected before making changes to settings that are dependent on the  
range. Q-RPTs selected with this command are used with their full default pressure range. The reply  
indicates the active range in psi if the RPM4 is a “US” version or in kPa if the RPM4 is an “SI” version.  
Used as a simple query, the active range is returned, which can be an AutoRanged range or a  
default range (see “ARANGE” cmd).  
Example  
(enhanced)  
Example  
(classic)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Sent:  
Reply:  
Sent:  
Reply:  
ERR# 6:  
ERR# 29:  
“RANGE? IL”  
“2.2 psi g,IL”  
“RANGE= IH”  
“1000 psi a, IH”  
“RANGE”  
“220 psi a,IL”  
Invalid Rng argument.  
The selected Q-RPT is not available.  
(select internal Lo Q-RPT in it’s full default range)  
(select internal Hi Q-RPT in it’s full default range)  
(request current range)  
See Also  
“ARANGE”, “RPT”  
3.2.3, 3.3.1, 3.3.4  
RATEn  
Purpose  
Query  
Read the next available pressure rate of change.  
“RATEn?”  
Classic  
“RATEn”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Remarks  
The next available pressure rate of change in the current pressure unit per second is returned.  
After receiving this program message, the RPM4 replies back with the data once a new pressure  
measurement cycle is complete. This can take up to the current read rate period (1.2 seconds  
by default).  
Example  
(enhanced)  
Example  
(classic)  
Query sent:  
Query reply:  
Sent:  
“RATE?”  
“0.01 kPa/s”  
“RATE2”  
“0.03 kPa/s”  
Reply:  
See Also  
“PRR”, “QPRR”.”READRATE”  
3.3.6.2  
Page 99  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
READRATEn  
Purpose  
Command  
Query  
Read or set the specified or active Q-RPT read rate or auto read rate mode.  
“READRATEn period”  
“READRATEn?”  
Classic  
“READRATEn= period”  
“READRATEn”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF and the HL  
Q-RPT is not active.  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT if the HL Q-RPT is not active and measurement  
mode is not differential.  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active.  
Period to integrate the measurement over (ms). Can be from 200 ms to 20000  
ms. Set to ‘0’ to enable automatic read rate.  
Arguments  
Remarks  
“period ":  
The RPM4 can have the speed in which it integrates each measurement (“read rate”) automatically  
adjusted based on the rate, or it can manually set to a fixed period. Increasing the read rate increases  
the reply time for pressure and rate queries. In differential mode and when using the HL Q-RPT, the Lo  
Q-RPT read rate is always set to the same read rate as the Hi.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
Reply:  
ERR# 6:  
ERR#10:  
“READRATE 1000”  
“1000”  
(No reply if GPIB-488)  
“READRATE? 1000”  
“1000”  
“READRATE=1000”  
“1000”  
The “period” argument is out of range.  
The suffix ‘n’ is invalid  
See Also  
“PR”, “PRR”, “SR”  
3.5.7.2  
READYCKn  
Purpose  
Command  
Query  
Read or set the Ready check flag.  
“READYCKn 1”  
“READYCKn?”  
Classic  
“READYCKn=1”  
“READYCKn”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Remarks  
The internal ready check flag is cleared whenever the specified or active Q-RPT reaches a  
Not Ready (NR) condition. The “READYCK” query returns the status of the flag. The flag is  
set by sending the “READYCK 1” program message while the Q-RPT is in a Ready condition.  
The “READYCK” program message query can then be used at a later time to determine  
whether a Not Ready condition has occurred since the ready check flag was set.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
“READYCK1 1”  
“1” (no reply if GPIB-488)  
“READYCK1?”  
“1”  
“READYCK?”  
(enhanced)  
“1” (if Q-RPT condition has stayed Ready)  
“0” (if Q-RPT condition has NOT stayed Ready)  
“READYCK=1”  
“READYCK=1”  
“READYCK”  
“READYCK=1” (if Q-RPT condition has stayed Ready)  
“READYCK=0” (if Q-RPT condition has NOT stayed Ready)  
Argument is not a ‘0’ or a ‘1’.  
Example  
(classic)  
Example  
(classic)  
Sent:  
Query reply:  
Sent:  
Query reply:  
Errors  
See Also  
ERR# 6:  
“SR”  
3.2.1  
© 2004-2007 DH Instruments, a Fluke Company  
Page 100  
4. REMOTE OPERATION  
REMOTE  
Purpose  
Command  
Classic  
Lock out the front panel keypads during remote operation.  
“REMOTE”  
“REMOTE”  
Remarks  
The RPM4 goes into remote mode whenever communications take place. The user can  
return to local operation by pressing the [ESC] key. The REMOTE program message locks  
out the front panel completely. The only way to unlock the front panel after the “REMOTE”  
command is using the “LOCAL” program message, the IEEE-488 “GTL” command, or by  
cycling the RPM4 power.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Cmd sent:  
Reply:  
Cmd sent:  
Reply:  
Sent:  
Reply:  
“REMOTE”  
“REMOTE” (no reply if IEEE-488)  
“REMOTE?”  
“REMOTE”  
“REMOTE”  
“REMOTE”  
See Also  
“LOCAL”  
RESn  
Purpose  
Command  
Query  
To read or set the pressure display resolution for the active range.  
“RESn res”  
“RESn”  
Classic  
“RESn= res”  
“RESn”  
Default  
“RESn=0.001”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Arguments  
Remarks  
res:  
The pressure display resolution in % span of the specified Q-RPT range (0.0001 to 1 %  
FS).  
The pressure display resolution is defined as % span of the active range. The setting is  
separate for each range, and changes as the range is changed.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
“RES .01”  
“0.01” (No reply if GPIB-488)  
“RES? .01”  
“0.01”  
“RES=.01”  
“0.01”  
The argument is invalid.  
Reply:  
ERR# 6  
See Also  
3.4.2  
RESET  
Purpose  
Command  
Classic  
Reset the user’s settings to factory defaults.  
“RESET”  
“RESET”  
Remarks  
The RPM4 has user settings (units, resolution, etc.) that can be reset to factory defaults. The  
remote “RESET” program message corresponds to the front panel “Reset - Sets”. System  
calibration coefficients and communications settings are not affected. The reset cycle takes up  
to 3 seconds to complete. Remote communications should not take place during this period.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Cmd sent:  
Reply:  
Cmd sent:  
Reply:  
Sent:  
Reply:  
“RESET”  
“RESET”  
“RESET?”  
“RESET”  
“RESET”  
“RESET”  
(no reply if IEEE-488)  
See Also  
3.5.9.1  
Page 101  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
RPTn  
Purpose  
Query  
Classic  
Read the available Q-RPT identification data.  
“RPTn”  
“RPTn”  
“n”  
Optional Suffix  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Remarks  
Up to two (three including the HL Q-RPT which is a combination of the Hi and Lo) internal Q-  
RPTs can be available for use in an RPM4. You can query the RPM4 for information about  
each particular Q-RPT. The Q-RPT data is returned in the following format:  
RPTLabel, Q-RPTLocator, Serial#, RngGa, RngAbs, Q-RPTMode  
RngLabel:  
RPT type label. This label identifies the Q-RPT type and range. This is  
the same label used on the RPM4 front panel screen.  
RptLocator:  
Text field identifying the Q-RPT position in the RPM4 system.  
“IH” identifies this as an internal, Hi Q-RPT  
“IL” identifies this as an internal, Lo Q-RPT  
Serial#:  
RngGa:  
RngAbs:  
The serial number of the Q-RPT.  
The Q-RPT default gauge mode range in the current pressure unit.  
The Q-RPT default absolute mode range in the current pressure unit.  
“NONE” appears in the field if the Q-RPT is a Gxxx, BGxxx or Axxx with  
absolute and negative gauge modes OFF.  
RptMode:  
‘A’ if Q-RPT is Axxx and supports absolute, gauge and negative gauge  
measurement modes.  
‘G’ if Q-RPT is gauge Gxxx or Axxx with absolute and negative gauge  
modes OFF and supports only gauge measurement mode.  
‘N’ if Q-RPT is BGxxx and supports gauge and negative gauge  
measurement modes.  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
ERR#4:  
“RPT2?”  
“A350K, IL, 82345, 35, 50,A”  
“RPT3” (Get information on the HL Q-RPT)  
“A7M, HL, 82345, 1000, 1000,A”  
External device not detected.  
Invalid suffix.  
(Get information on the Lo Q-RPT)  
ERR# 10:  
See Also  
3.2.3, 3.2.4  
SDSn  
Purpose  
Read or set the OPEN/CLOSE status for the specified or active Q-RPT SDS systems. This  
is equivalent to use of the SDS temporary OPEN/CLOSE function from the RPM4 front panel.  
Command  
Query  
“SDSn close”  
“SDSn”  
Classic  
“SDSn=close”  
“SDSn”  
Default  
“SDSn=1”  
Optional Suffi  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT’s SDS if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT’s SDS if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT’s SDS.  
‘3’ Specify the HL Q-RPT’s SDS if the HL Q-RPT is active  
Arguments  
Remarks  
”close:  
‘0’ to OPEN the SDS system.  
‘1’ to CLOSE the SDS system.  
Each Q-RPT of designation A7M or less can have an “SDS” system, which can be either  
“OPEN” or “CLOSED”. This command allows access to each one without affecting the other,  
regardless of whether the SDS for the selected Q-RPT is currently full time “ON” or “OFF”.  
Caution must be used in differential mode or when using the HL Q-RPT, as this command  
can allow you to have one Q-RPT open while the other Q-RPT is closed. If the “HL” Q-RPT  
SDS is specified, then both the Hi and the Lo Q-RPT SDS will be affected. This command  
does not affect the power up status of the SDS system.  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
ERR# 7:  
“SDS2? 1”  
“1”  
“SDS1=0”  
“SDS1=0”  
(close the Lo Q-RPT SDS)  
(open the Hi Q-RPT SDS)  
Argument not a ‘0’ or a ‘1’  
ERR# 10:  
ERR# 23:  
ERR# 53:  
Invalid suffix.  
SDS not installed on this Q-RPT and pressure is close to ATM.  
SDS not installed on this Q-RPT and pressure not close to ATM.  
See Also  
“SDSAUTO”, “SDSACT”  
3.2.7, 3.3.8, 3.5.4  
© 2004-2007 DH Instruments, a Fluke Company  
Page 102  
4. REMOTE OPERATION  
SDSACT  
Purpose  
Read or set the status for both the Hi and Lo Q-RPT’s SDS systems. This is equivalent to  
use of the [SDS] key from the RPM4 front panel.  
Command  
Query  
“SDS state”  
“SDS”  
Classic  
“SDS=state”  
“SDS”  
Default  
“SDS=1”  
Arguments  
”state”:  
‘0’ OPEN the SDS system on the active Q-RPT and CLOSE the SDS  
system on the “inactive” Q-RPT.  
‘1’ to CLOSE the SDS system on both Q-RPTs.  
Remarks  
This command can be used to select one Q-RPT at a time, ensuring that the “inactive” Q-RPT  
SDS is closed. If a Q-RPT’s SDS is full time “OFF”, then it is not be affected by this  
command. The status of the active Q-RPT’s SDS system is replied. If the RPM4 is in  
differential mode or the HL Q-RPT is active, then this command opens or close both the Hi  
and Lo SDS at the same time, unless the SDS is full time “off”.  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
ERR# 7:  
“SDS? 1”  
“1”  
“SDS=0”  
“SDS=0”  
Argument not a ‘0’ or a ‘1’  
Invalid suffix or command argument.  
SDS not installed on this Q-RPT  
ERR# 10:  
ERR# 23:  
See Also  
“SDSAUTO”, “SDS”  
3.2.7, 3.3.8, 3.5.4  
SDSAUTOn  
Purpose  
Read or set the automatic full time ON/OFF status for the specified or active Q-RPT SDS  
systems. This is equivalent to use of the SDS full time ON/OFF function from the RPM4  
front panel.  
Command  
Query  
Classic  
“SDSAUTOn on”  
“SDSAUTOn”  
“SDSAUTOn=on”  
“SDSAUTOn”  
“SDSAUTOn=1”  
Default  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given. If the “HL” Q-RPT is the active Q-  
RPT, and no suffix is specified, then the “Hi” Q-RPT is assumed  
‘1’ Specify the Hi Q-RPT SDS  
‘2’ Specify the Lo Q-RPT SDS  
Arguments  
Remarks  
on:  
‘0’ to turn the SDS system OFF.  
‘1’ to turn the SDS system ON  
Turning an SDS system to full time “OFF” or “ON” affects how the remote command  
“SDSACT” and the front panel SDS button can affect each Q-RPT’s SDS system.  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
ERR# 7:  
“SDSAUTO2? 1”  
“1”  
“SDSAUTO1=0”  
“SDSAUTO1=0”  
Argument not a ‘0’ or a ‘1’  
Invalid suffix.  
ERR# 10:  
ERR# 23:  
SDS not installed on this Q-RPT  
See Also  
“SDSACT”, “SDS”  
3.2.7, 3.3.8, 3.5.4,  
SCRSAV  
Purpose  
Command  
Query  
Read or set the front panel display screen saver activation time.  
“SCRSAV n”  
“SCRSAV?”  
“SCRSAV=n”  
“SCRSAV”  
Classic  
Arguments  
Default  
n:  
The inactivity period (0 – 99 minutes) after which screen saver activates.  
“SCRSAV 10”  
Remarks  
The RPM4 front panel will dim after a period of keyboard and remote inactivity. Setting this  
value to ‘0’ disables this feature.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
“SCRSAV 30”  
“30”  
“SCRSAV? 30”  
“30”  
“SCRSAV=30”  
“30”  
The argument was invalid.  
(No reply if GPIB-488)  
Reply:  
ERR# 6  
See Also  
3.5.5.1  
Page 103  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
SN  
Purpose  
Query  
To read the serial number of the RPM4.  
“SN?”  
Classic  
“SN”  
Remarks  
Example  
(enhanced)  
Example  
(classic)  
See Also  
The RPM4 is serialized. The serial number can be read using this program message.  
Query sent:  
Query reply:  
Sent:  
“SN?”  
“321”  
“SN”  
Reply:  
“321”  
3.5.5.4  
SR  
Purpose  
Query  
Classic  
Optional Suffix  
Read the next available Ready/Not Ready status.  
“SR?”  
“SR”  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Remarks  
The current Ready status can be read using this program message.  
Possible replies:  
“NR”  
“R ”  
The pressure is not ready within the limits defined by the stability criterion.  
The pressure meets the ready criteria. The status is replied when the next pressure  
measurement is finished.  
“OL”  
The pressure of one of the active Q-RPTs has exceeded the user defined upper or  
lower limits.  
“OP”  
“ER”  
The pressure of one of the Q-RPTs has exceeded the Q-RPT’s maximum limits.  
An internal device failure has occurred.  
Example  
(enhanced)  
Example  
(classic)  
Query sent:  
Query reply:  
Sent:  
“SR?”  
“NR”  
“SR”  
“NR”  
Reply:  
See Also  
“PR”, “PRR”, “HS”, “SS”, “UL”, “LL” Commands  
3.2.1, 3.4.4, 3.4.4.1  
SS%n  
Purpose  
Command  
Query  
Read or set the current stability limit as a % of range.  
“SS% limit”  
“SS%?”  
Classic  
“SS%=limit”  
“SS%”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Arguments  
Remarks  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
limit:  
The stability limit in %FS of the current active range.  
The stability limit can be read and set as a percent of the full scale range of the Q-RPT range.  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
“SS% .1”  
“0.10 %”(No reply from GPIB-488)  
“SS%? .1”  
“0.10 %”  
“SS%=.1”  
“0.10 %”  
Reply:  
Errors  
ERR# 6:  
ERR# 10:  
“SS”  
The argument was invalid.  
Invalid or missing command suffix.  
See Also  
3.4.3  
© 2004-2007 DH Instruments, a Fluke Company  
Page 104  
4. REMOTE OPERATION  
SSn  
Purpose  
Command  
Query  
Read or set the current pressure stability limit.  
“SS limit”  
“SS?”  
Classic  
“SS=limit”  
“SS”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Arguments  
Remarks  
Limit:  
The stability limit in the current pressure unit of measure.  
The stability limit can be read and set as a pressure. The stability limit is used as the  
Ready/Not Ready criteria..  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
“SS .1”  
“0.10 kPa/s”  
“SS? .1”  
“0.10 kPa/s”  
“SS=.1”  
“0.10 kPa/s”  
The argument was invalid.  
Invalid or missing command suffix.  
(No reply from GPIB-488)  
Reply:  
ERR# 6:  
ERR# 10:  
“SS%”  
See Also  
3.4.3  
TIME  
Purpose  
Command  
Query  
Read or set the RPM4 internal clock.  
“TIME hh:mmXX”  
“TIME?”  
Classic  
“TIME=hh:mmXX”  
“TIME”  
Arguments  
hh:mm:  
XX:  
The time in a 12 hour format using a colon delimiter  
”am” or “pm”  
“TIME 12:52PM”  
“12:52pm”  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
(No reply if GPIB-488)  
“TIME? 12:52PM”  
“12:52pm”  
“TIME=12:52PM”  
“12:52pm”  
Reply:  
ERR# 7:  
“DATE”  
3.5.5.3  
Missing or improper program message argument(s).  
See Also  
UCOEFn  
Purpose  
Query  
To identify the coefficient used to convert 1 Pascal to the current pressure unit of measure.  
“UCOEFn?”  
Classic  
“UCOEFn”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active  
Remarks  
The RPM4 handles all pressure values internally in Pascal. The coefficient replied is  
equivalent of 1 Pa in the current pressure unit of measure. This program message allows the  
user to convert pressures  
Example  
(enhanced)  
Example  
(classic)  
Query sent:  
Query reply:  
Sent:  
“UCOEF?”  
“0.0010000000”  
“UCOEF”  
“0.0010000000”  
Reply:  
See Also  
3.3.2, 3.5.6, 7.2.1  
Page 105  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
UDU  
Purpose  
Command  
Query  
Read or set the user defined pressure unit.  
“UDU label, ucoef”  
“UDU?”  
Classic  
“UDU=label, ucoef”  
“UDU”  
label:  
User unit label (4 alphanumeric char maximum). It cannot be an already  
supported unit label.  
Ucoef:  
“User unit conversion coefficient (units/Pa).  
Default  
“UDU USER,1.0”  
Remarks  
The user defined unit must be set up with the program message prior to remote or local  
selection.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(enhanced)  
Errors  
Cmd Sent:  
Query reply:  
Cmd Sent:  
Query reply:  
Sent:  
“UDU MYUN, .001”  
“MYUN, 0.001000”  
“UDU? MYUN, .001”  
“MYUN, 0.001000”  
“UDU=MYUN, .001”  
“MYUN, 0.001000”  
(No reply if GPIB-488)  
Reply:  
See Also  
3.5.6, 3.3.2  
ULn  
Purpose  
Command  
Query  
Read or set an upper limit for the specified or active Q-RPT.  
“Uln limit”  
“Uln?”  
Classic  
“Uln=limit”  
“ULn”  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF and the HL  
Q-RPT is not active.  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT if the HL Q-RPT is not active and measurement  
mode is not differential.  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active.  
The upper limit pressure in the specified Q-RPT’s current pressure unit and  
measurement mode. If the unit is meters, this value is be interpreted in kPa. If  
the unit is feet, this value is be interpreted in psi.  
Arguments  
Remarks  
“limit":  
The RPM4 has an upper limit for each range and for each measurement mode (gauge, absolute, and  
differential). If the pressure does exceed the upper limit, the pressure display flashes. This  
feature should always be used to prevent accidental over pressure of a device under test.  
Example  
(enhanced)  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
Reply:  
ERR# 6:  
“LL”  
“UL 1000”  
“1000.00 kPa a” (No reply if GPIB-488)  
“UL? 1000”  
“1000.00 kPa a”  
“UL=1000”  
“1000.00 kPa a”  
The “limit” argument is out of range.  
See Also  
3.4.4  
© 2004-2007 DH Instruments, a Fluke Company  
Page 106  
4. REMOTE OPERATION  
UNITn  
Purpose  
Command  
Read or set the pressure unit of measure unit and measurement mode.  
“UNITn unit (, ref”)”  
“UNITn unitn (, ref”)”  
“UNITn unitg (, ref”)”  
“UNITn unita (, ref”)”  
“UNITn unitd (, ref”)”  
“UNITn?”  
Query  
Classic  
“UNITn=unit (, ref”)”  
“UNITn=unitn (, ref”)”  
“UNITn=unitg (, ref”)”  
“UNITn=unita (, ref”)”  
“UNITn=unitd (,ref”)”  
“UNITn”  
Optional Suffix  
Arguments  
Remarks  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ Specify the Hi Q-RPT if the Hi and Lo Q-RPTs are NOT OFF and the HL  
Q-RPT is not active.  
Specify the HL Q-RPT if the Hi and Lo Q-RPTs are OFF  
‘2’ Specify the Lo Q-RPT if the HL Q-RPT is not active and measurement  
mode is not differential.  
‘3’ Specify the HL Q-RPT if the HL Q-RPT is active.  
The text corresponding to the pressure unit of measure. A unit mode  
character can optionally be added to the end of the units:  
‘a’ for absolute measurement mode.  
Unit:  
ref:  
‘g’ for gauge measurement mode.  
‘n’ for negative gauge measurement mode.  
‘d’ for differential measurement mode (Hi Q-RPT only)  
The optional unit reference temperature only if the unit is “InWa”  
This program message determines what unit of measure and what measurement mode is used to  
display pressure values. Refer to Table 13 for a detailed list of the units available and their labels.  
If the unit text is not followed by an explicit mode character (‘a’, ‘g’, ‘n’ or ‘d’) then “gauge” mode is  
assumed. There can be a space between the unit text and the ‘a’, ‘g’, ‘n’ or ‘d’.  
If the unit specified is “InWa”, an optional second argument “ref” can be set. The “ref” can be 4, 20,  
or 60 corresponding to InWa at 4 °C, 20 °C or 60 °F. If this second argument is not given when  
the unit is “InWa”, then the reference temperature is assumed to be 20 °C. This can also be added  
directly onto the end of the Unit argument if desired.  
The fifth character of the reply is always ‘a’ for absolute mode, ‘g’ for gauge/negative gauge mode  
or ‘d’ for differential mode. White spaces precede this character if needed. The temperature  
reference is added to the reply only if the unit is “InWa”.  
The reply includes the measurement mode character in the fifth position, with an ‘a’ indicating  
absolute mode, a ‘g’ indicating gauge or negative gauge mode or a ‘d’ indicating differential mode.  
The “MODE” command can also be used to set the desired measurement mode only.  
Example  
(enhanced)  
Cmd sent:  
Query reply:  
Sent:  
Query reply:  
Sent:  
Query reply:  
Cmd sent:  
Query reply:  
Sent:  
“UNIT? kPaa”  
“kPaa”  
“UNIT? InWag, 4”  
“inWag, 4”  
“UNIT? InWaa60”  
“inWaa, 60”  
“UNIT psi n”  
“psi g”  
“UNIT=kPaa”  
“kPaa”  
Example  
(enhanced)  
Example  
(classic)  
(‘g’ used to indicate both gauge & neg gauge modes)  
Reply:  
Sent:  
Reply:  
“UNIT=InWag, 4”  
“inWag, 4”  
Errors  
ERR# 7:  
ERR# 6:  
ERR# 20:  
The unit is invalid.  
The ref is invalid.  
Absolute measurement mode and altitude units are not allowed with a gauge Q-RPT.  
See Also  
“MMODE”, “MODE”  
3.3.2, 3.3.3, 3.5.6, 7.2.1  
VER  
Purpose  
Query  
Identify the RPM4, US or SI units, the Q-RPT labels and the software version.  
“VER?”  
Classic  
Remarks  
“VER”  
The software version of the RPM4 can be read. This is useful for checking for the presence of the  
RPM4 and for reference purposes. It indicates the internal Q-RPT(s) and software version.  
Example  
(enhanced)  
Example  
(classic)  
Query sent:  
Query reply:  
Query sent:  
Query reply:  
“ID”, “*IDN?”  
None  
“VER?”  
“DH INSTRUMENTS, INC RPM4 us A350K/BG15K Ver1.00 ”  
“VER?”  
“DH INSTRUMENTS, INC RPM4 us A350K/BG15K Ver1.00 ”  
See Also  
Page 107  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
ZOFFSETn  
Purpose  
Read or set the AutoZ pressure offset (Poffset) for the specified or active Q-RPT in the current  
measurement mode.  
Command  
Query  
“ZOFFSETn GaOffset , AbsOffset , DifOffset”  
“ZOFFSETn?”  
Classic  
“ZOFFSETn =GaOffset , AbsOffset , DifOffset”  
“ZOFFSETn”  
Defaults  
“ZOFFSETn = 0.0, 0.0, 0.0”  
(Gauge Q-RPT)  
“ZOFFSETn = 101325, 0.0, 0.0” (Absolute Q-RPT)  
Optional Suffix  
“n”  
The active Q-RPT is assumed if no suffix is given.  
‘1’ “:HI” Specify the Hi Q-RPT  
‘2’ “:LO” Specify the Lo Q-RPT  
Arguments  
Remarks  
GaOffset:  
AbsOffset:  
DifOffset:  
The Q-RPT pressure offset (“Poffset”) for Gauge measurement mode (Pa).  
The Q-RPT pressure offset for absolute measurement mode (Pa)  
The Q-RPT pressure offset for differential measurement mode (Pa)  
The pressure offset (Poffset) for the specified Q-RPT (Hi or Lo) can be accessed with this  
program message. There are separate offsets for gauge, absolute and differential  
measurement modes, but not all modes apply in all cases. Gauge Q-RPTs do not support  
AbsOffset”. “DifOffset” applies only to the “Hi” Q-RPT.  
Using this program message overwrites the current offset, so caution must be used.  
Changes made using this program message take effect immediately.  
Example  
(enhanced)  
Example  
(classic)  
Errors  
Cmd sent:  
Query reply:  
Sent:  
“ZOFFSET1 2.1, 0, 0”  
2.10 Pa, 0.00 Pa, 0.00 Pa”  
“ZOFFSET=97293.1, 3.02, 0”  
97293.10, 3.02, 0.00”  
One of the arguments is out of range.  
Reply:  
ERR# 6:  
3.5.1  
See Also  
4.5  
STATUS REPORTING SYSTEM  
The RPM4 status reporting system is used to track and report system status and errors. It follows the  
model of the IEEE Std 488.2 and works for the COM1 and the IEEE-488 port with slight differences. The  
RPM4 can be programmed to respond to various status conditions by asserting the SRQ of the IEEE-488  
interface. The COM1 port cannot be supported in such a way, so polling must be used.  
4.5.1  
ERROR QUEUE  
The RPM4 keeps track of remote errors by using an error queue. If an error occurs, it is pushed  
onto the Error Queue. If you are using the COM1 port, the error number is immediately  
replied in the form “ERR#nn where nn is the error code from 0 to 99. The “ERR?” (or “ERR”)  
query can then be used to pull the error from the Error Queue in it’s descriptive text format.  
If you are using the enhanced program message format, the Error Queue will accumulate  
errors until full unless they are pulled from the queue. If you are using the classic program  
format, the Error Queue is cleared every time a new program message is received.  
4.5.2  
STATUS BYTE REGISTER  
The RPM4 contains an 8 bit Status Byte Register that reflects the general status of the  
RPM4.  
Table 18. 8 Bit Status Byte Register  
OPER  
RQS/MSS  
ESB  
MAV  
N/A  
ERROR  
N/A  
RSR  
(128)  
(64)  
(32)  
(16)  
(8)  
(4)  
(2)  
(1)  
This register is affected by the RPM4 reply output queue, the Error Queue, the Standard  
Event Status register and the Ready Event Status register.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 108  
4. REMOTE OPERATION  
Status Byte Register  
(“STB?” or ”SRE n”)  
OPER  
(128)  
Standard Event Status Register  
RQS/MSS  
(64)  
(“ESR?” or “ESE n”)  
ESB  
←←←  
(32)  
PON  
URQ  
CMD  
EXE  
DDE  
QYE  
RQC  
OPC  
(128)  
(64)  
(32)  
(16)  
(8)  
(4)  
(2)  
(1)  
MAV  
←←←  
(16)  
OUTPUT  
QUEUE  
N/A  
(8)  
ERROR  
←←←  
(4)  
ERROR  
QUEUE  
Ready Event Status Register  
N/A  
(2)  
(“RSR?” or ” RSE n”)  
RSR  
N/A  
MEAS  
HI  
NDRY  
HI  
RDY  
LO  
N/A  
MEAS  
HI  
NRDY  
HI  
RDY  
HI  
←←←  
(1)  
(128)  
(8)  
(64)  
(32)  
(16)  
(4)  
(2)  
(1)  
Figure 6. Status Register Schematic  
The Status Byte Register can be read using the “*STB?” query, or by performing a serial poll  
on the IEEE-488 bus. If you read this using a serial poll then Bit 6 is the RQS. If the  
“*STB?” query is used, then bit 6 is the MSS bit. All of the other bits are common to both types  
of query.  
Each of these status bits can cause a SRQ to occur. The Service Request Enable Register  
(“*SRE” program message ) determines which of these flags are able to assert the SRQ line.  
This enable register has a matching set of bits that each will enable the designated bit to  
cause a SRQ, except for the RQS/MSS bit(s) which cannot cause a SRQ. If you set this  
register to 20 ($14 hex), an SRQ will occur if the MAV or the ERROR bit are set. The  
description of these bits are given as:  
OPER  
RQS  
N/A Bit 7 (128)  
Requested Service Bit 6 (64)  
Indicates that the SRQ line of the IEEE-488 interface has been asserted by the  
RPM4. This bit is cleared when a serial poll is performed on the RPM4, and is a  
part of the Status Byte Register when read using a serial poll. This bit does not  
apply if the COM1 port is being used.  
MSS  
Master Summary Status Bit 6 (64)  
Indicates that an event or events occurred that caused the RPM4 to request service  
from the Host, much like the RQS bit. Unlike the RQS bit, it is READ ONLY and can  
be only cleared when the event(s) that caused the service request are cleared.  
ESB  
Event Summary Bit 5 (32)  
Indicates if an enabled bit in the Standard Event Status Register became set  
(see Section 4.5.3).  
MAV  
Message Available Bit 4 (16)  
Indicates that at least one reply message is waiting in the RPM4 IEEE-488 output  
queue.  
ERROR  
RSR  
Error Queue Not Empty Bit 2 (4)  
Indicates that at least one command error message is waiting in the RPM4 IEEE-  
488 error message queue. Use the “ERR?” query to get this message.  
Ready Summary Bit 0 (1)  
Indicates that an enabled bit in the Ready Status Register became set.  
Page 109  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
4.5.3  
STANDARD EVENT REGISTER  
The RPM4 contains an 8 bit Standard event register that reflects specific RPM4 events.  
Enabled events in this register will set or clear the ESB bit of the Status Byte Register.  
Table 19. 8 Bit Standard Event Register  
PON  
URQ  
CMD  
EXE  
DDE  
QYE  
RQC  
OPC  
(128)  
(64)  
(32)  
(16)  
(8)  
(4)  
(2)  
(1)  
This register can be read using the “*ESR?” query, Each of these status bits can set the ESB  
bit of the Status Byte Register, causing a SRQ to occur IF the ESB bit is enabled to do so.  
The Standard Event Status Enable Register (“*ESE” program message ) determines which of  
these flags are able to assert the ESB bit. The description of these bits are given as:  
PON  
URQ  
CMD  
EXE  
DDE  
QYE  
Power On Bit 7 (128)  
Indicates that the RPM4 power has been cycled since the last time this bit was  
read or cleared.  
User Request Bit 6 (64)  
Indicates that the RPM4 was set to local operation manually from the front panel  
by the user (pressing the [ESC] key).  
Command Error Bit 5 (32)  
Indicates that a remote command error has occurred. A command error is  
typically a syntax error in the use of a correct program message.  
Execution Error Bit 4 (16)  
Indicates if a remote program message cannot be processed due to device  
related condition.  
Device Dependent Error Bit 3 (8)  
Indicates that an internal error has occurred in the RPM4 such as a transducer time-  
out.  
Query Error Bit 2 (4)  
Indicates that an error has occurred in the protocol for program message  
communications. This is typically caused by a program message being sent to  
the RPM4 without reading a waiting reply.  
RQC  
OPC  
Request Control Bit 1 (2)  
This bit is not supported as the RPM4 cannot become the active controller in charge.  
Operation Complete Bit 0 (1)  
Indicates that the RPM4 has completed all requested functions.  
4.5.4  
READY STATUS REGISTER  
The RPM4 contains an 8 bit Ready Status Register that reflects specific RPM4 Q-RPT  
measurement ready events. Enabled events in this register will set or clear the RSB bit of  
the Status Byte Register.  
Table 20. 8 Bit Ready Status Register  
N/A  
MEAS  
LO  
NRDY  
LO  
RDY  
LO  
N/A  
MEAS  
HI  
NRDY  
HI  
RDY  
HI  
(128)  
(8)  
(64)  
(32)  
(16)  
(4)  
(2)  
(1)  
© 2004-2007 DH Instruments, a Fluke Company  
Page 110  
4. REMOTE OPERATION  
This register can be read using the “*RSR?” query, Each of these status bits can set the  
RSB bit of the Status Byte Register, causing a SRQ to occur IF the RSB bit is enabled to do so.  
The Standard Event Status Enable Register (“*RSE” program message ) determines which  
of these flags are able to assert the RSB bit. The description of these bits are given as:  
MEAS LO Lo-RPT measurement ready Bit 6 (64)  
Indicates that the Hi Q-RPT has completed a Q-RPT measurement.  
NRDY LO Lo Q-RPT pressure Not Ready Bit 5 (32)  
Indicates that the Hi Q-RPT made a transition from Ready to Not Ready as  
defined by the stability settings (see Section 3.2.1).  
RDY LO  
Lo Q-RPT pressure Ready Bit 4 (16)  
Indicates that the Hi Q-RPT is Ready as defined by the stability settings (see  
Section 3.2.1).  
MEAS HI Hi Q-RPT measurement ready Bit 2 (4)  
Indicates that the Hi Q-RPT has completed a Q-RPT measurement.  
NRDY HI Hi Q-RPT pressure Not Ready Bit 1 (2)  
Indicates that the Hi Q-RPT made a transition from Ready to Not Ready as  
defined by the stability settings (see Section 3.2.1).  
RDY HI  
Hi Q-RPT pressure Ready Bit 0 (1)  
Indicates that the Hi Q-RPT is Ready as defined by the stability settings (see  
Section 3.2.1).  
4.6  
IEEE STD. 488.2 COMMON AND STATUS PROGRAM  
MESSAGES  
The RPM4 supports a set of commands that are common to all instruments conforming to IEEE Std. 488.2.  
These command make it easy to perform basic function for any device that supports these commands.  
These commands also cover the status reporting commands. See Section 4.5 for details on the status  
registers mentioned in these commands.  
Table 21. Program Message List  
Clear all of the status & event structures.  
CLS  
ESE  
ESR  
IDN  
Read or set the Standard Event Status Enable Register.  
Read the Standard Event Status Register.  
Identify the RPM4 version, range, and serial number.  
Set the operation complete bit when all operations have completed.  
Read the list of installed RPM4 options.  
OPC  
OPT  
RST  
TST  
SRE  
STB  
RSE  
RSR  
Reset the RPM4 settings to factory settings.  
Read the power on self test status.  
Read or set the Service Request Enable Register.  
Read the Status Byte Register.  
Read or set the Ready Status Enable Register.  
Read the Ready Status Register.  
Page 111  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
4.6.1  
PROGRAM MESSAGE DESCRIPTIONS  
CLS  
Purpose  
Command  
Remarks  
Clear all of the status & event structures.  
CLS”  
This program message clears the following events and status registers:  
Standard Byte Register (STB)  
Standard Event Status Register (ESR)  
Error Queue  
Pending OPC operations  
Example  
Sent:  
Reply:  
CLS”  
none  
ESE  
Purpose  
Command  
Query  
Read or set the Standard Event Status Enable Register.  
ESE n”  
ESE?”  
ESE 0”  
Default  
Arguments  
n:  
’0 to 255’ This is the decimal representation of the bit(s) to enable. To enable  
the PON and QYE bits, the argument would be 128 + 4 = 132.  
Remarks  
The Standard Event Status Enable register determines which bits in the standard Event  
Status Register are enabled and included in the Status Byte Register (ESB bit), and can  
assert the SRQ line. The reply is in decimal numeric form.  
Example  
(enhanced)  
Errors  
Sent:  
Query reply:  
ERR# 6:  
ESE=128”(enables the PON bit)  
“128” (no reply if IEEE-488)  
n is not valid.  
ESR  
Purpose  
Command  
Remarks  
Read the Standard Event Register.  
ESR?”  
The Standard Event Register contents are cleared after reading. The reply is in decimal  
numeric form.  
Example  
(enhanced)  
Sent:  
Reply:  
ESR?”  
“20” (the QYE and EXE bits are set)  
IDN  
Purpose  
Query  
Identify the RPM4 version, range, and serial number.  
IDN?”  
Remarks  
The identification reply is made up of the manufacture, the model, the serial number and the  
software version. Each is separated by a comma.  
Sent:“IDN?”  
Example  
(enhanced)  
Reply:“DH INSTRUMENTS INC, RPM4 A0100/A0015, 1234, Ver2.00 -dhf”  
OPC  
Purpose  
Command  
Query  
Sets the operation complete bit when all operations have completed.  
OPC”  
OPC?”  
Remarks  
This Command enables the RPM4 to set the OPC bit in the Standard Event Status Register  
when it has completed all pending functions.  
The Query replies with a “1” when all functions are complete.  
Example  
(enhanced)  
Sent:  
Query reply:  
OPC”  
“1”  
OPT  
Purpose  
Reads the list of installed RPM4 options.  
Query  
OPT?”  
Remarks  
This Query returns any registered option(s) installed in the RPM4. Each option is separated  
by a comma. Possible options:  
“IEEE-488:0”  
The IEEE-488 option is installed,  
Example  
(enhanced)  
Sent:  
Reply:  
OPT?”  
“IEEE-488:0”  
RST  
Purpose  
Command  
Remarks  
Resets the RPM4 settings to factory settings.  
RST””  
This Command sets the RPM4 settings to factory settings. This equivalent to a front panel  
executed RESET/SET. This does not affect the communications settings.  
Example  
(enhanced)  
Sent:  
Reply:  
RST”  
RST” (no reply if IEEE-488)  
See Also  
Section 3.5.4.1, Reset – Sets  
© 2004-2007 DH Instruments, a Fluke Company  
Page 112  
4. REMOTE OPERATION  
SRE  
Purpose  
Command  
Query  
Read or set the Service Request Enable Register.  
SRE n”  
SRE?”  
SRE 0”  
Default  
Arguments  
n:  
’0 to 255’ This is the decimal representation of the bit(s) to enable. To allow the  
MAV and ESB bits to assert the SRQ line, the argument would be 32 + 16 = 48.  
Bit 6 (64) is reserved and cannot be set.  
Remarks  
The Service Request Enable Register determines which bits of the Status Byte can set the MSS  
bit of the Status Byte and request service by asserting the SRQ line of the IEEE-488 interface.  
Example  
(enhanced)  
Errors  
Sent:  
Query reply:  
ERR# 6:  
SRE=48” (enables the MAV and ESB bits)  
“48” (no reply if IEEE-488)  
n is not valid.  
STB  
Purpose  
Command  
Remarks  
Read the Status Byte Register.  
STB?”  
The Status Byte Register reflects the general status of the RPM4. The ‘MSS’ bit state is  
represented by bit 6.  
Example  
(enhanced)  
Sent:  
Reply:  
STB?”  
“80” (The MSS and MAV bits are set)  
TST  
Purpose  
Read the power on self test status.  
Query  
TST?””  
Remarks  
The RPM4 system memory stores the user settings (units, resolution) and retains them when  
the unit if OFF. On power-up, this memory is checked. If this memory is corrupted, all user  
settings are reset to default (as if the “RST” program message was executed), and the TST  
query will return a non zero value. If the RPM4 passed the test on power-up OR if the TST  
query was used at least once since the RPM4 was powered up the reply will be a ‘0’.  
Example  
(enhanced)  
Sent:  
Reply:  
RST?”  
“1”  
*RSE  
Purpose  
Command  
Query  
Read or set the Ready Status Enable Register.  
“RSE n”  
“RSE?”  
“RSE 0”  
Default  
Arguments  
Remarks  
n:  
’0 to 255’ This is the decimal representation of the bit(s) to enable. To enable  
the RDY bit, the argument would be 1.  
The Ready Status Enable Register determines which bits in the Ready Status Register are  
enabled and included in the Status Byte Register (RSR bit), and can assert the SRQ line.  
The reply is in decimal numeric form.  
Example  
(enhanced)  
Errors  
Sent:  
Query reply:  
ERR# 6:  
RSE=1” (enables the RDY bit)  
“1” (no reply if IEEE-488)  
n is not valid.  
*RSR  
Purpose  
Command  
Remarks  
Read the Ready Status Register.  
“RSR?”  
The Ready Status Register contents are cleared after reading. The reply is in decimal  
numeric form.  
Example  
Sent:  
“RSR?”  
(enhanced)  
Reply:  
“6” (The MEAS and NRDY)  
Page 113  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
NOTES  
© 2004-2007 DH Instruments, a Fluke Company  
Page 114  
5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS  
5. MAINTENANCE,  
ADJUSTMENTS AND CALIBRATION  
5.1  
OVERVIEW  
RPM4 was designed for maintenance free operation. No maintenance is required other than:  
Regular AutoZeroing of quartz reference pressure transducer(s) (Q-RPT) (see Section 3.5.1).  
Periodic calibration of Q-RPT(s) (see Section 5.2).  
Adjustment of the on-board barometer, if present (see Sections 5.3).  
This section provides information on maintenance, adjustment and calibration procedures, and recommended  
overhaul procedures.  
RPM4 is a sophisticated pressure measuring instrument with advanced on-board features and  
functions. Before assuming that unexpected behavior is caused by a system defect or breakdown, use  
this manual and other training facilities to become thoroughly familiar with RPM4 operation.  
For rapid assistance in specific situations see Chapter 6 for troubleshooting information.  
RPM4 is covered by a limited one (1) year warranty. Unauthorized service or repair during the warranty  
period is undertaken at the owner’s risk and may cause damage that is not covered under warranty  
and/or may void the warranty. For warranty service, contact a DHI Authorized Service Provide (see  
Table 29).  
5.2  
CALIBRATION OF QUARTZ REFERENCE PRESSURE  
TRANSDUCERS (Q-RPTS)  
5.2.1  
PRINCIPLE  
RPM4 is equipped with one or two quartz reference pressure transducers (Q-RPTs)  
used for low uncertainty pressure measurement.  
To calibrate a Q-RPT, pressures from a reference standard are applied to the Q-RPT at  
ascending and descending pressure increments over the range. The recommended  
pressure sequence for a calibration varies depending on whether the Q-RPT is of Standard or  
Premium class (see Section 1.2.2.1). The pressure defined by the standard and the  
corresponding Q-RPT readings are recorded at each point. After all of the pressures have  
been applied and recorded, adjustments are made to fit the Q-RPT pressure readings to the  
standard. Fitting the readings means performing a linear regression to arrive at the lowest  
value of the residuals of errors of the Q-RPT relative to the standard. The Q-RPT output is  
adjusted by user settable coefficients: PA (an adder or offset) and PM (a multiplier or span  
set) (see Section 5.2.1.1).  
Page 115  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
The calibration process is performed independently on each Q-RPT to arrive at its optimal fit.  
CalTool for RPTs software provided with the RPM4 supports the calibration process of  
RPM4 Q-RPTs. CalTool and its documentation are provided on a General Accessories Disk with a  
new RPM4 and can be downloaded from www.dhinstruments.com. Most users should use  
CalTool software to assist in the calibration of RPM4.  
RPM4 is delivered with an interactive Q-RPT calibration utility that steps the operator through  
the complete Q-RPT calibration procedure including applying the necessary pressures,  
collecting data automatically, calculating new PA and PM values, previewing the results of  
the new calibration and activating the results of the new calibration (see the CalTool for RPTs  
manual on the General Accessories Disk). RPM4 also provides complete front panel and  
remote access to Q-RPT calibration parameters so that Q-RPT calibrations can be performed  
without using CalTool software (see Section 5.2.8).  
5.2.1.1  
PA AND PM COEFFICIENTS  
The coefficients used to adjust Q-RPT readings are designated PA (an adder or  
offset) and PM (a multiplier or span set). The coefficients affect the Q-RPT  
reading following:  
Corrected reading = (uncorrected reading • PM) + PA  
PA is expressed in units of pressure (always the SI unit, Pascal).  
PM is dimensionless.  
Each Q-RPT has its own unique PA and PM values. The PA and PM values  
currently in use can be viewed and edited from the front panel in the CAL  
function (see Section 5.2.7). PA and PM values are automatically edited when  
CalTool software results are activated.  
As editing PA and PM values will change Q-RPT calibration, they should only  
be edited by qualified personnel as part of the calibration process. Caution  
should be taken to avoid accidental editing and a security system is  
available to prevent access (see Section 3.5.5.5). Incorrect editing of PA  
and PM values can cause out of tolerance measurements.  
A new RPM4 is delivered with PA and PM values set to zero and 1 for all  
ranges. This does not mean that the RPM4 has not been calibrated. In the  
original factory calibration, privileged factory coefficients are used for  
calibration with the user PA and PM set to zero and 1.  
5.2.1.2  
AS RECEIVED AND AS LEFT DATA  
Frequently, calibration procedures require that as received and as left data be  
reported. The necessary information to report as received and as left data on the  
calibration of RPM4 Q-RPTs can be obtained in several ways.  
When the RPM4 CalTool calibration assistance software is used, as received  
data is displayed while running the calibration and is automatically recorded and  
reported if desired. As left data is also calculated and presented.  
At any time, a) reference pressures applied; b) associated Q-RPT readings;  
c) PA and PM and Poffset values, can be used to calculate as received and as left values.  
For example, backing out PA and PM on the as left data yields the Q-RPT  
© 2004-2007 DH Instruments, a Fluke Company  
Page 116  
5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS  
readings with PA = 0 and PM = 1. Then applying the as received PA and PM  
and Poffset values to the readings calculates as received readings (the readings  
that the transducer would have made with the old PA, PM and Poffset).  
It is recommended that “as received” values of PA, PM and Poffset (for Axxx  
Q-RPTs if absolute mode AutoZero is used in normal operation) be recorded for  
each Q-RPT prior to running the calibration. The current PA, PM and Poffset (for  
Axxx Q-RPTs) can be viewed by pressing [SPECIAL], <8cal>, <1view>.  
5.2.2  
EQUIPMENT REQUIRED  
The recommended calibration standards for RPM4 Q-RPTs are DHI PG7000 piston  
gauges (PG7102, PG7202, PG7601 for gas; PG7302 for oil). Contact DHI for additional  
information.  
5.2.2.1  
GAS OPERATED Q-RPTS, A10M AND LOWER  
Gas operated piston gauge (deadweight tester), with the following  
characteristics:  
Measurement uncertainty of ± 0.0025 % of reading for Standard Class  
Q-RPTs or ± 0.002 % of reading for Premium Class Q-RPTs. A standard  
with higher measurement uncertainty may be used but RPM4 measurement  
uncertainty may be degraded proportionally from published specifications.  
If the Q-RPT is Axxx (absolute) and will be used in the absolute and/or  
negative gauge measurement modes, the reference must be able to apply  
absolute pressures: Absolute pressures may be defined either by operation  
relative to an evacuated bell jar or, for higher pressures, by addition of  
atmospheric pressure measured by a suitable barometer. Axxx (absolute)  
Q-RPTs that will not be used in absolute or negative gauge  
measurement modes (as is often the case for higher pressure Q-RPTs)  
do not require the application of absolute pressure for calibration and  
may be calibrated using a gauge pressure standard.  
Axxx (absolute) Q-RPTs calibrated in gauge measurement mode by  
applying gauge reference pressure values should be used in gauge mode  
only (see Sections 3.3.3,  PRINCIPLE, 5.2.5).  
Able to supply the recommended sequence of pressure points in the  
range to be calibrated:  
See Section 5.2.4 for information on the  
recommended calibration point sequence for various Q-RPT types  
and classes.  
5.2.2.2  
OIL OR GAS OPERATED Q-RPTS A14M AND HIGHER  
Gas or oil operated piston gauge (deadweight tester), with the following  
characteristics:  
Do not put oil or other liquids in a Q-RPT that is meant to be operated  
with gas.  
Page 117  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
Measurement uncertainty of ± 0.008 % of reading for Standard Class  
Q-RPTs or ± 0.005 % of reading for Premium Class Q-RPTs. A standard  
with higher measurement uncertainty may be used but RPM4 measurement  
uncertainty may be degraded proportionally from published specifications.  
If the Q-RPT is Axxx (absolute) and will be used in the absolute and/or  
negative gauge measurement modes, the reference must be able to apply  
absolute pressures: Absolute pressures may be defined by adding  
atmospheric pressure measured by a barometer to gauge pressure defined by a  
piston gauge. Axxx (absolute) Q-RPTs that will not be used in absolute or  
negative gauge measurement modes (as is very often the case for higher  
pressure Q-RPTs) do not require the application of absolute pressure  
for calibration and may be calibrated using a gauge pressure standard.  
Axxx (absolute) Q-RPTs calibrated in gauge measurement mode by  
applying gauge reference pressure values should be used in gauge mode  
only (see Sections 3.3.3,  PRINCIPLE, 5.2.5).  
Able to supply the recommended sequence of pressure points in the  
range to be calibrated:  
See Section 5.2.4 for information on the  
recommended calibration point sequence for various Q-RPT types and  
classes.  
5.2.3  
SET-UP AND PREPARATION  
To set-up and prepare an RPM4 for calibration of a Q-RPT:  
Set the RPM4 on a stable surface near the calibration standard at a height as close as  
possible to the calibration standard’s reference height. Consider the connections that  
may need to be made to the rear panel and access to the front panel display and keypad.  
Connect the calibration standard output to the TEST(+) port of the Q-RPT module to be  
calibrated on the RPM4 rear panel (1/8 in. NPT F or DH500F depending on range, see  
Section 2.3.5).  
If the Q-RPT module has a TEST(-) port, leave it unobstructed or connect it to the  
reference standard’s TEST(-) port if available.  
Open SDS (Self Defense System) if present (see Section 3.3.8) for the Q-RPT to be  
calibrated. When the RPM4 indicates <SDS CLOSED>, the TEST(+) port is isolated from  
the Q-RPT to be calibrated.  
Opening SDS with a pressure greater than Pmax! applied to the test port may cause  
overpressure damage to the Q-RPT.  
The Q-RPTs of RPM4s used in parallel measurement mode must be adjusted separately.  
PA and PM for the Hi and Lo Q-RPT need to be determined and set individually. Therefore,  
data to be used in determining calibration coefficients cannot be taken in parallel mode  
(see Section 3.5.7.3). Do not run a calibration with the HL (parallel mode) Q-RPT active.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 118  
5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS  
5.2.4  
RECOMMENDED CALIBRATION POINT SEQUENCE  
Calibration adjustments to RPM4 Q-RPTs are made by altering calibration coefficients,  
PA and PM (see Section 5.2.1.1). To adjust these coefficients to optimum values giving the  
best results over the Q-RPTs complete operating range, specific calibration point sequences  
are recommended. The recommended point sequence depends upon whether the Q-RPT  
being calibrated is a Standard or Premium Class (see Section 1.2.2.1). The class of the  
RPM4 Q-RPTs is indicated in the model number on the product label and on the rear panel  
Q-RPT label (<s> for standard, <p> for premium, for example A7Ms or A7Mp).  
Prior to running the calibration point sequence, the Q-RPT should be exercised by:  
a) Setting full scale pressure.  
b) Dwelling at full scale pressure for 5 minutes.  
c) Returning to atmospheric pressure (vented). If the Q-RPT is a gas operated Axxx type,  
use vacuum rather than atmospheric pressure.  
d) Dwelling for twenty minutes.  
A dwell time after setting the pressure of at least 60 seconds before taking data at each point  
is recommended.  
Section 5.2.4.1 gives calibration point sequences for Standard Class Q-RPTs and Section 5.2.4.2  
gives calibration point sequences for Premium Q-RPTs.  
It is not required that the calibration pressure standard apply precisely the nominal  
pressure value of each calibration point as long as the exact value of the applied pressure  
is known. Best results are obtained if the actual applied pressure is within 2 % of the  
recommended nominal point.  
5.2.4.1  
STANDARD CLASS Q-RPTS  
See additional information in Section 5.2.4 concerning exercising the Q-RPT and  
dwell time at pressure points.  
Table 22. Calibration Point Sequence, Standard Class,  
Axxx and Gxxx Q-RPTs  
CALIBRATION  
SEGMENT  
POINT  
NO.  
POINT  
[% OF SPAN]  
Lowest Pressure1  
25 %  
1
2
3
4
5
6
7
8
9
Ascending  
50 %  
75 %  
100 %  
75 %  
50 %  
Descending  
25 %  
Lowest Pressure1  
1. In absolute mode, the lowest point that can be set reliably by  
the reference piston gauge, or atmospheric pressure for ranges  
> A1.4M. Zero (vented) in gauge mode.  
Axxx (absolute) Q-RPTs that will NOT be used in absolute or  
negative gauge measurement modes may be calibrated in  
gauge measurement mode with a gauge pressure standard.  
Axxx (absolute) Q-RPTs calibrated in gauge measurement  
mode should be used in gauge mode only (see Sections 3.3.3,  
 PRINCIPLE, 5.2.5).  
Page 119  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
Table 23. Calibration Point Sequence, Standard Class,  
BGxxx Q-RPTs  
CALIBRATION  
SEGMENT  
POINT  
NO.  
POINT  
[% OF SPAN]1  
1
2
3
4
5
6
7
8
9
0 %  
25 %  
50 %  
75 %  
100 %  
75 %  
50 %  
25 %  
0 %  
Ascending  
Descending  
1. The BG15K span is  
15 to  
+
15 kPa, 30 kPa total.  
Therefore, 0 % is – 15 kPa, 25 % is – 7.5 kPa, 100 % is  
+ 15 kPa, etc.  
BGxxx (bi-directional gauge) Q-RPTs that will NOT be used  
in negative gauge measurement mode may be calibrated in  
gauge (positive pressures) measurement mode only. Use the  
Standard Class gauge mode (Gxxx) calibration point  
sequence (see Table 22). BGxxx Q-RPTs calibrated in gauge  
measurement mode only should not be used in negative  
gauge mode.  
Table 24. Calibration Point Sequence, Standard Class,  
BA100K Q-RPT  
CALIBRATION  
SEGMENT  
POINT  
NO.  
POINT  
[% OF SPAN]1  
1
2
3
4
5
6
7
8
9
0 %  
25 %  
50 %  
75 %  
100 %  
75 %  
50 %  
25 %  
0 %  
Ascending  
Descending  
1.  
The BA100K span is 70 to 110 kPa absolute.  
5.2.4.2  
PREMIUM CLASS Q-RPTS  
See additional information in Section 5.2.4 concerning exercising the Q-RPT and  
dwell time at pressure points.  
Verification of Premium Class Q-RPTs  
When verifying (as opposed to calibrating) a Premium Q-RPT, it is not necessary  
to include the higher density of points that is recommended for determination of the  
calibration coefficients. A 5 points up, 2 points down (50%, low point) run is  
adequate. To verify that the uncertainty turndown with AutoRange (see Sections  
3.3.4, 1.2.2.1) is in tolerance, it is recommended that the verification of a Premium  
Q-RPT include verification of an AutoRanged span of 30 % of the maximum  
Q-RPT span. For example, verify an A7M Q-RPT in the default range of 0 to 7 MPa  
(1 000 psi) and in the AutoRange range of 2.1 MPa (300 psi).  
© 2004-2007 DH Instruments, a Fluke Company  
Page 120  
5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS  
Table 25. Calibration Point Sequence, Premium Class,  
Axxx and Gxxx Q-RPTs  
CALIBRATION  
SEGMENT  
POINT  
NO.  
POINT  
[% OF SPAN]  
Lowest Pressure1  
5 %  
1
2
3
10 %  
4
15 %  
5
20 %  
Ascending  
6
30 %  
7
40 %  
8
50 %  
9
60 %  
10  
11  
12  
13  
14  
15  
80 %  
100 %  
80 %  
50 %  
Descending  
20 %  
Lowest Pressure1  
1
In absolute mode, lowest point that can be set reliably by the  
reference piston gauge. Zero (vented) in gauge mode.  
Axxx (absolute) Q-RPTs that will NOT be used in absolute or  
negative gauge measurement modes may be calibrated in  
gauge measurement mode with a gauge pressure standard.  
Axxx (absolute) Q-RPTs calibrated in gauge measurement  
mode should be used in gauge mode only (see Section 5.2.5).  
Table 26. Calibration Point Sequence, Premium Class,  
BGxxx Q-RPTs  
CALIBRATION  
SEGMENT  
POINT  
NO.  
POINT  
[% OF SPAN]1  
1
2
3
4
5
6
7
8
9
10  
11  
12  
13  
14  
15  
0 %  
15 %  
30 %  
40 %  
45 %  
50 %  
55 %  
60 %  
70 %  
85 %  
100 %  
70 %  
50 %  
30 %  
0 %  
Ascending  
Descending  
1. The BG15K span is – 15 to + 15 kPa, 30 kPa total. Therefore,  
0 % is – 15 kPa, 25 % is – 7.5 kPa, 100 % is + 15 kPa, etc.  
BGxxx (bi-directional gauge) Q-RPTs that will not be used in  
negative gauge measurement mode may be calibrated in  
gauge (positive pressures) measurement mode only. Use the  
Premium Class gauge mode (Gxxx) calibration point sequence  
(see Table 25).  
BGxxx Q-RPTs calibrated in gauge  
measurement mode only should not be used in negative  
gauge mode.  
Page 121  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
5.2.5  
TURNING OFF ABSOLUTE AND NEGATIVE GAUGE  
MEASUREMENT MODES FOR AXXX (ABSOLUTE) Q-RPTS  
 PURPOSE  
To prevent operation in absolute and negative gauge measurement modes on an Axxx  
(absolute) Q-RPT that has been calibrated for gauge mode only.  
 PRINCIPLE  
Axxx (absolute) Q-RPTs are frequently used in gauge measurement mode only (see Section  
3.3.3,  PRINCIPLE). Axxx Q-RPTs that are used in gauge mode only, may be calibrated in  
gauge mode with a reference that applies gauge pressures. Calibration with an absolute  
reference is not necessary. However, if an Axxx Q-RPT is calibrated in gauge mode, it is not  
possible to know if it is in or out of tolerance in absolute and negative gauge modes. To avoid  
using absolute and negative gauge measurement modes with an Axxx Q-RPT that is  
calibrated for gauge mode only, access to absolute and negative gauge modes can be turned  
OFF. This is accomplished in the [SPECIAL], <8cal> menu.  
 OPERATION  
See Section 5.2.7 for more detailed information on editing and viewing Q-RPT calibration  
information.  
Turning absolute and negative gauge mode operation ON and OFF for a Q-RPT occurs in the  
same area in which calibration coefficients are edited. To access the Q-RPT calibration editing area  
press [SPECIAL], <8cal> and select the desired Q-RPT. Then select <1edit> to make changes.  
Allow abs and  
HI  
[ENT] through the calibration information screens.  
After viewing the values of PA and PM the display is:.  
neg g mode? 1yes 2no  
The cursor is on the number corresponding to the current selection. Make the desired selection.  
<1no> causes absolute and negative gauge modes to be unavailable for the Q-RPT.  
5.2.6  
5.2.7  
Q-RPT CALIBRATION USING CALTOOL FOR RPTS  
SOFTWARE  
To calibrate RPM4 Q-RPTs using CalTool software, refer to Sections 5.2.1,  
 PRINCIPLE, 5.2.2, and 5.2.3 in this manual and then refer to the CalTool for  
RPTs Software Manual.  
CalTool for RPTs software and manual are supplied on the RPM4  
General Accessories Disk and can be downloaded from www.dhinstruments.com.  
EDITING AND VIEWING Q-RPT CALIBRATION  
INFORMATION  
 PURPOSE  
View and/or edit Q-RPT calibration information fields including:  
The calibration date – This field is normally used to record the date on which the Q-RPT  
is calibrated.  
The value of absolute mode AutoZero Poffset (Axxx Q-RPTs only) – See Section 3.5.1  
for complete AutoZero information. This value is normally set to zero following absolute  
measurement mode calibration of an Axxx Q-RPT.  
The value of PA – The pressure adder for the selected Q-RPT (see Sections 5.2.1.1).  
The value of PM – The pressure multiplier for the selected Q-RPT (see Sections 5.2.1.1).  
© 2004-2007 DH Instruments, a Fluke Company  
Page 122  
5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS  
Absolute and negative gauge measurement modes ON or OFF (Axxx Q-RPTs only)  
– See Section 3.3.3,  PRINCIPLE for complete information on measurement modes.  
This is set to OFF if an Axxx Q-RPT was calibrated in gauge mode with a gauge  
pressure standard.  
 OPERATION  
As editing PA and PM values will change the calibration of the Q-RPTs, the edit function  
should only be used by qualified personnel as part of the calibration process. Caution  
should be taken to avoid accidental editing. A user level security system is available to  
control access (see Section 3.5.5.5).  
A new RPM4 is delivered with PA and PM values set to zero and 1 for all ranges. This does  
not mean that the RPM4 has not been calibrated. In the original factory calibration, privileged  
factory coefficients are used for calibration with the user PA and PM set to zero and 1.  
To access Q-RPT calibration information viewing or editing press [SPECIAL], <8Cal>.  
Select the desired Q-RPT. The <1view> selection displays the calibration information fields.  
The <2edit> function displays the fields and allows them to be edited. The display is:  
1. Date of last calibration in YYYYMMDD format.  
Cal date:20030325 Hi  
AbsPoffset: 0.0 Pa  
2. Position designator of the Q-RPT being viewed.  
3. Current value of absolute mode Poffset  
.
This line is blank if the Q-RPT is not an Axxx type.  
If in edit mode, the calibration information fields can be edited. Edits to Poffset are common  
with changes made in the AutoZ edit or run function (see Section 3.5.1). Pressing [ENT] on  
the last field goes to the next view/edit screen:  
1. Value of PA.  
PA: 0.0 Pa  
Hi  
2. Position designator of the Q-RPT being viewed.  
3. Value of PM.  
PM: 1.000000  
If in edit mode, the calibration fields can be edited. If the selected Q-RPT is an Axxx Q-RPT,  
pressing [ENT] in the PM field goes to the next calibration information display (this display is  
skipped if the Q-RPT is a Gxxx or BGxxx type):  
1. Position designator of the Q-RPT being viewed.  
Absolute and  
Hi  
2. Cursor is on current ON or OFF selection.  
neg g mode: 1on 2off  
The cursor is on the current setting. If in edit mode, the ON or OFF status can be changed  
by selecting <1on> or <2off> (see Section 5.2.5). [ENT] in view mode returns to the  
view/edit screen. [ENT] in edit mode goes to confirmation of change activation if changes have  
Page 123  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
been made in any of the calibration screens. Pressing [ESC] in any edit screen exits the edit screen  
without activating any changes.  
The value of PA is always in Pascal (Pa). The value of PM is dimensionless.  
5.2.8  
Q-RPT CALIBRATION/ADJUSTMENT WITHOUT CALTOOL  
FOR RPTS SOFTWARE  
 PRINCIPLE  
The RPM4 Q-RPTs can be calibrated and adjustments made without using CalTool for RPTs  
software. This requires:  
Applying pressures with a calibration standard and recording the pressures measured by RPM4.  
Calculating new PA and PM values and entering them.  
Setting Poffset to zero for Axxx Q-RPTs.  
Before proceeding to calibrate a reference pressure transducer without using CalTool for RPTs  
software, Sections 5.2, Calibration of Reference Pressure Transducers, 5.2.1  PRINCIPLE,  
5.2.2 Equipment Required, 5.2.3 Setup and Preparation should be reviewed thoroughly.  
The Q-RPTs of RPM4s used in parallel measurement mode must be adjusted separately.  
PA and PM for the Hi and Lo Q-RPT need to be determined and set individually. Therefore,  
data to be used in determining calibration coefficients cannot be taken in parallel mode  
(see Section 3.5.7.3).  
 OPERATION  
The typical procedure for calibrating a Q-RPT is:  
Set-up and prepare the RPM4 for calibration (see Sections 5.2.2, 5.2.3).  
Use the [RANGE] function key to select the Q-RPT to be calibrated (see Section 3.3.1).  
Be sure to set the DF range (not an AutoRanged range).  
Use [HEAD] to set the HEAD to zero (see Section 3.3.7). Use [UNIT] to set the desired  
pressure unit of measure (see Section 3.3.2). Use [MODE] to set the desired pressure  
measurement mode (see Section 3.3.3). Axxx (absolute) Q-RPTs that will be used in  
gauge measurement mode only, may be calibrated in gauge measurement mode with a  
gauge pressure standard (see Section 5.2.5).  
Use [SPECIAL], <1AutoZ> to access the AutoZ function (see Section 3.5.1).  
If calibrating in absolute measurement mode, turn AutoZ ON if it is left ON in normal  
RPM4 operation.  
If calibrating in gauge measurement mode, always turn AutoZ ON.  
Use [SPECIAL], <8cal>, <1Hi RPT> or <2Lo RPT>, <1view>, to read and record the  
current values of PA and PM for the Q-RPT to be calibrated. If calibrating in absolute mode,  
also record the value of Poffset  
.
© 2004-2007 DH Instruments, a Fluke Company  
Page 124  
5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS  
Run the recommended calibration point sequence for the Q-RPT (see Section 5.2.4).  
Record the pressure applied by the standard and the RPM4 reading at each calibration  
point. Dwell at least 60 seconds at each point after setting the reference pressure to  
allow full stabilization The data recorded is the “as received” data for this calibration.  
Enter the calibration pressures and RPM4 readings into a spreadsheet. Calculate the  
“non-corrected” RPM4 readings by backing out the PA, PM and Poffset (Poffset in the case of  
Axxx (absolute) Q-RPTs in absolute mode only, do not back out Poffset for for gauge mode  
calibrations) recorded in Steps and above, following:  
non-corrected reading = ((corrected reading - PA)/PM ) + Poffset  
Perform a linear regression to find the offset and slope that best fit the non-corrected  
RPM4 readings to the calibration standard pressures. The offset is the new value of PA,  
the slope is the new value of PM.  
Press [SPECIAL], <8Cal>, <1Hi RPT> or <2Lo RPT>, <2edit> and write the new  
calibration date and the new values of PA and PM for the Q-RPT calibrated (see Section  
5.2.7). If this is an Axxx Q-RPT and the calibration was performed in gauge mode, turn  
absolute and negative gauge modes OFF to avoid their being used after the calibration.  
Calculate as left data for the calibration if desired following:  
as left reading = (non-corrected reading • new PM) + new PA  
Perform additional verification pressure runs as desired.  
5.3  
ADJUSTMENT OF ON-BOARD BAROMETER  
 PURPOSE  
To adjust the output of the on-board barometer (see Section 1.2.2.2).  
RPM4’s that have only G100K or G200K Q-RPTs (no Axxx or G15K or BGxxx) are NOT equipped with an  
on-board barometer.  
 PRINCIPLE  
The on-board barometer output can be adjusted using PA and PM values in the same manner as  
Q-RPTs (see Section 5.2.1.1).  
The on-board barometer is a low accuracy sensor used only for measuring changes in atmospheric  
pressure over short periods of time (see Section 3.2.2) and the line pressure for G15KK and BG15K  
line pressure compensation. RPM4 measurement uncertainty does not depend on the measurement  
uncertainty of the on-board barometer.  
 OPERATION  
To edit the values of PA and PM for the barometer, press [SPECIAL], <8cal>, <3barometer>. Pressing  
[ENT] steps through displays of the calibration date (YYYYMMDD) and PA and PM. In edit mode, the  
values can be edited. Pressing [ENT] after the last screen activates the edited values.  
To view the current output of the on-board barometer, press [SPECIAL], <7Internal>, <3baro>.  
Page 125  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
5.4  
RELOADING EMBEDDED SOFTWARE INTO FLASH  
MEMORY  
RPM4 uses FLASH memory. This allows the embedded software that controls RPM4 operations and  
functions to be loaded into RPM4 over its COM1 port from a computer with a simple FLASH loading utility  
program.  
To replace corrupted software or upgrade your software, access the DHI worldwide web site at  
www.dhinstruments.com and go to SOFTWARE. A FLASH loading utility and the latest RPM4  
software are available for download at no charge. If you do not have access to the web or have difficulty  
downloading or loading software, contact your DHI representative or a DHI Authorized Service Provider  
(see Table 29) for assistance.  
If you believe you have discovered an error or “bug” in RPM4 software, please report it with complete  
details by email to [email protected] or submit an on-line Quality Feedback Report  
under CALIBRATION & REPAIR at www.dhinstruments.com.  
The DHI flash software loading utility and RPM4 embedded software are available for download from  
www.dhinstruments.com in the SOFTWARE section.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 126  
5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS  
5.5  
SUBASSEMBLY DESCRIPTION AND LOCATION  
1. Micro Card  
3. Driver Board  
6. Hi Q-RPT module  
(< A7M style shown)  
2. Power Supply Module  
(beneath Driver Board)  
4. On-Board Barometer (if present)  
7. Display  
5. Lo Q-RPT module (if present)  
(< A7M style shown)  
Figure 7. Internal View  
5.5.1  
MINI MICRO BOARD  
The micro board supports a Motorola 68302 micro-controller, EPROM, EEPROM, 128k x 16  
bit NVRAM, 8 Mbit flash memory; RS-232 and IEEE-488.2 communications; keypad and  
display control. An I/O port controls other ports and devices in RPM4.  
5.5.2  
POWER SUPPLY MODULE  
+ 12 V DC (± 2 %) @ 2.1 Amps  
Page 127  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
5.5.3  
DRIVER BOARD  
The driver board is controlled by the mini micro board (see Section 5.5.1). It supports:  
12 V drivers for internal solenoid valve actuation  
Frequency counters (2) for reading Q-RPTs (see Section 5.5.5)  
On-board barometer power and output (see Section 5.5.4)  
Utility sensor (if present) power and output  
Power to the system cooling fan  
Remote [ENT]  
Keypad and display  
Beeper  
5.5.4  
ON-BOARD BAROMETER  
The on-board barometer supports a board mounted, barometric range, micromachined  
silicon sensor and an ambient temperature sensor. The barometer readings are used for  
dynamic atmospheric pressure compensation when measuring gauge pressure with an  
absolute quartz reference pressure transducer (see Section 3.2.2). The temperature sensor  
is used for temperature compensation of the barometric sensor.  
RPM4s that have only G100K or G200K Q-RPTs (no Axxx or G15K or BGxxx) are NOT  
equipped with an on-board barometer.  
5.5.5  
Q-RPT MODULE  
The Q-RPT module is an integrated Quartz Reference Pressure Transducer (Q-RPT)  
assembly. The module includes a Q-RPT, brackets to hold the transducer, interconnecting  
tubing, a manifold with TEST(+),TEST(-) (A70M and lower only) and VENT (ATM on A100M  
and higher) ports and SDS (Self Defense System) solenoid valves (A7M and lower, gas  
operated, only).  
A Q-RPT provides very high precision, low uncertainty pressure measurement. The basic  
sensing principle is the measurement of the change in the natural oscillating frequency of a  
quartz tuning fork in response to changes in temperature and mechanical stress resulting  
from the change in pressure applied to a connecting bellows or bourdon tube. Two independent  
quartz elements are used. One quartz element is subjected to pressure related stress. The  
other quartz element is used only to monitor temperature. See Section 1.2.2.1 for Q-RPT  
specifications.  
See Figure 8 for pneumatic schematics of different Q-RPT module configurations.  
5.5.5.1  
HI Q-RPT MODULE  
RPM4 is always equipped with a Hi Q-RPT module. The Hi Q-RPT module is in  
the Hi Q-RPT position. It is always the higher range in two Q-RPT RPM4s.  
5.5.5.2  
LO Q-RPT MODULE  
RPM4 may be equipped with a Lo Q-RPT module. The Lo Q-RPT provides a  
lower measurement range than the Hi Q-RPT. See Section 1.2.2.1 for complete  
Q-RPT specifications.  
5.5.6  
DISPLAY  
2 x 20 character vacuum fluorescent display.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 128  
5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONS  
5.6  
Q-RPT MODULE PNEUMATIC SCHEMATICS  
Axxx Q-RPT >A10M  
(No SDS)  
Axxx Q-RPT <A10M  
VALVE  
STATE  
CONDITION  
A
B
O
C
C
C
O
O
SDS Open  
SDS Closed  
Power off  
Gxxx or BGxxx Q-RPT  
VALVE  
STATE  
CONDITION  
A
O
C
C
B
C
C
O
O
C
SDS Open  
SDS Closed  
Power off  
O
O
Figure 8. Pneumatic/hydraulic schematics of RPM4 with Single Q-RPT Module  
Page 129  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
The pneumatic schematic for RPM4’s with two Q-RPT modules is the same as for the single Q-RPT  
modules in Figure 8 with the following exceptions:  
If both modules use the barometer, the barometer is connected to teed to both module barometer  
connection points.  
An exception is the combination of an Axxx with SDS (<A10M) and a G15K or BGxxx shown below.  
Axxx Q-RPT <A10M with G15K or  
BGxxx  
Figure 9. Pneumatic/hydraulic schematics of RPM4 with Two Q-RPT Modules  
© 2004-2007 DH Instruments, a Fluke Company  
Page 130  
6. TROUBLESHOOTING  
6. TROUBLESHOOTING  
RPM4 is a sophisticated pressure setting and measuring instrument with advanced on-board features  
and functions. Before assuming that unexpected behavior is caused by a system defect or breakdown,  
the operator should use this manual and other training facilities to become thoroughly familiar with  
RPM4 operation. This troubleshooting guide is intended as an aid in identifying the reason for RPM4  
behavior and determining whether the behavior is due to normal operation or an internal or external problem.  
Identify the symptom or unexpected behavior you are observing from the SYMPTOM list below.  
A PROBABLE CAUSE is provided and a SOLUTION is proposed including references to manual  
sections that provide information that may be of assistance.  
Table 27. Troubleshooting Guide  
SYMPTOM  
Will not power up.  
PROBABLE CAUSE  
SOLUTION  
Blown fuse.  
Replace fuse.  
Cannot access certain functions  
>ACCESS RESTRICTED<  
User level has been set that restrict access  
to certain functions.  
Change user level or consult system  
manager. 3.5.5.5  
Cycle power to clear. Please record  
conditions leading up to event including  
the numbers displayed when [ENT] is  
pressed and report to your DHI  
Displays <FATAL ERROR> or  
<FATAL FAULT>.  
Encountered unresolved internal software  
conflict.  
Authorized Service Provider. Table 29  
Front panel keys seem to be  
disabled.  
<remote> command has been sent from a  
host computer.  
Send <local> command from host  
computer or cycle RPM4 power. 4, 4.4.4  
Measured pressure display or  
other displays have too much/not  
enough resolution.  
Resolution setting needs to be changed.  
Change resolution setting. 3.4.2  
Resolution setting is limited when  
AutoRanging under 10 % of Q-RPT default  
range.  
Can’t increase resolution to level  
desired in AutoRanged range.  
Operation is normal. Table 6  
Values that should be non-zero  
are displayed as zero.  
Resolution setting needs to be increased to  
view significant digits.  
Change resolution setting. 3.4.2  
Keypad presses make undesired  
sounds or NO sounds.  
Use keypad function to set keypad  
sounds as desired. 3.5.5.2  
Keypad sound settings are incorrect.  
Bottom line of display has  
changed and you want to change  
it back.  
The DISPLAY function has been used to  
change the display.  
Use [DISPLAY] to set bottom line to  
desired display. 3.3.6  
Second line of display is  
<PPC3 EXT DEV:>  
and front keypad is locked out.  
The RPM4 has been initialized as an  
external device to a PPC3 pressure  
controller and is still in external device mode.  
Cycle RPM4 power to take it out of  
external device mode and restore local  
operation. 3.2.5  
Operation is normal. Use [DISPLAY] to  
change bottom line display if desired.  
3.3.6  
Bottom line of display is blank.  
DISPLAY mode is “clean”.  
The pressure units available  
under the [UNIT] function key are  
not the ones you want.  
Use PresU function to customize the  
UNIT function or reset units to default.  
3.5.6  
UNIT function needs to be customized.  
Screen saver option has activated.  
Operation is normal. Press any key to  
resume full screen power. Adjust screen  
saver time, if desired. 3.5.5.1  
Front panel display is dim.  
Page 131  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
SYMPTOM  
PROBABLE CAUSE  
SOLUTION  
The Q-RPT range does not cover the desired Check that Q-RPT default range is high  
AutoRange.  
enough to cover the AutoRange. Table 1  
The specified operating mode is absolute or  
negative gauge and absolute and negative  
modes are OFF for the desired Q-RPT  
AutoRange is not selecting the  
desired Q-RPT for the specified  
range.  
Check that absolute/negative gauge is ON  
for the Q-RPT. 5.2.5  
The Q-RPT is Gxxx (gauge only) and the  
specified operating mode is absolute or  
negative gauge..  
Check that the Q-RPT type supports the  
desired measurement mode. 3.3.3  
Range will NOT change. Displays The pressure currently applied to the range  
Reduce pressure applied to test port to  
less than UL of target range. 3.4.4  
“Pressure on Hi (or Lo) RPT  
exceeds RR upper limit”.  
that is being selected exceeds the UL (upper  
limit) set for that range.  
Pressure display is flashing and  
beeper is sounding intermittently.  
Current upper limit of active range has been  
exceeded.  
Reduce pressure. Change UL and/or  
active range if needed. 3.4.4  
Pressure display is flashing and  
beeper is sounding intermittently  
while operating in differential  
mode.  
Reduce differential pressure and/or  
pressure on Hi Q-RPT to be less than  
upper limit values or change upper limit  
value(s). 3.4.4, 3.3.3.1  
Differential pressure upper limit OR Hi Q-  
RPT upper limit is exceeded.  
Pressure display is NOT flashing  
and beeper is sounding  
intermittently while operating in  
differential mode.  
Lo Q-RPT upper limit is exceeded. If Lo Q-  
RPT is displayed on second line, its  
measured pressures is flashing.  
Reduce pressure on Lo Q-RPT or  
change its upper limit. 3.4.4, 3.3.3.1  
“Hi (or Lo) RPT EXCEEDED  
PMAX” displays alternating with  
normal display.  
Correct the overpressure condition and  
cycle power ON and OFF to clear.  
3.4.4.1  
RPM4 Q-RPT has been overpressured  
(Pmax! exceeded).  
If parallel measurement mode is not  
desired, change ranges or turn it off.  
If parallel measurement is desired,  
check that the Hi and Lo Q-RPTs are  
connected to the same pressure.  
RPM4 is in parallel measurement mode and  
the disagreement in pressure measured by  
the two Q-RPTs indicates they may not be  
connected in parallel.  
Rapid beeping for 8 seconds and  
<Check RPT connection>  
displayed in second line.  
Ignore if having the two Q-RPTs on two  
different pressures is intentional. 3.5.7.3  
A Ready (green Ready/Not Ready Stability settings is too tight and/or existing  
Adjust stability setting or correct other  
conditions. 3.4.3, 3.2.1  
indicator) indication is never  
achieved.  
conditions will not allow Ready to be  
achieved.  
Cannot select absolute or negative  
gauge measurement mode.  
Q-RPT is Gxxx and does not support  
absolute and gauge measurement modes or  
Operation is normal. 3.3.3  
RPM4 must have two Q-RPTs of the same  
type (Axxx, Gxxx, BGxxx) and the current  
range must be the default range (<DF>) of  
the Hi Q-RPT for differential measurement  
mode to be available.  
If RPM4 has two Q-RPTs of the same type,  
set the default range of the Hi Q-RPT.  
3.3.3.1  
Cannot select differential  
measurement mode.  
Q-RPT is Axxx (absolute) but  
cannot select absolute or negative mode have been turned off in the calibration  
gauge measurement mode.  
Absolute and negative gauge measurement  
Check that absolute/negative gauge is ON  
for the Q-RPT. 5.2.5  
function.  
Display update rate of indicated  
pressure changes when changing  
pressure.  
RPM4 automated read rate function is ON to  
automatically adjust read rate depending  
upon rate of change of pressure.  
Operation is normal. Turn automated  
read rate function OFF if desired. 3.5.7.2  
Pressure is changing but display  
of pressure is NOT and the  
bottom right hand corner of the  
display is a numerical countdown  
followed by <avg>.  
Average DISPLAY function is ON and  
pressure display is updating only with the  
average value at the end of each averaging  
cycle.  
Go to a DISPLAY function other than  
average or press [+/-] to get the  
instantaneous value Average DISPLAY.  
3.3.6  
Display update of indicated  
pressure is too slow when  
pressure is changing quickly.  
Turn automated read rate function ON to  
automatically adjust read rate depending  
on pressure rate of change. 3.5.7.2  
RPM4 automated read rate function is OFF.  
Purge and clean affected systems.  
Contact DHI Authorized Service  
Provider if RPM4 is contaminated  
internally. Table 29  
Pressure measurement seems  
erratic when measuring gas  
pressure.  
The RPM4 and/or the connection to the test  
system is contaminated with liquids.  
Pressure indicated by RPM4  
never becomes stable.  
These is a leak in the pressure system to  
which RPM4 is connected.  
Find and correct leak. Consider using  
RPM4 leak check function. 3.3.5  
© 2004-2007 DH Instruments, a Fluke Company  
Page 132  
6. TROUBLESHOOTING  
SOLUTION  
SYMPTOM  
PROBABLE CAUSE  
Compare differences observed to  
tolerances on Q-RPT measurements.  
1.2.2.1  
Disagreement between two Q-RPTs Difference is actually within tolerance and  
in system appears excessive.  
acceptable disagreement.  
Apparent inaccurate pressure  
control/measure and little or no  
response from Q-RPT:  
Reference transducer destroyed by  
overpressure.  
Contact DHI Authorized Service Provider.  
Table 29  
Set desired pressure units and/or  
measurement mode. Consider reference  
temperature if unit is inWa. 3.3.2, 3.3.3  
Incorrect pressure units and/or measurement  
mode (gauge or absolute).  
Apparent inaccurate pressure  
measurement.  
Q-RPT calibration coefficients have been  
altered.  
Check and correct calibration coefficients if  
needed. 5.2  
AutoZ has been run and turned ON with an  
incorrect standard for zero.  
Check value of Poffset. Rerun AutoZ with a  
valid reference. 3.5.1  
Apparent inaccurate pressure  
measurement and <h> is  
displayed on top line of screen.  
An unplanned “head” correction is active or  
head height or fluid is incorrect.  
Operation is normal. Remove or change  
“head” correction. 3.3.7  
Need to run AutoZ to rezero in gauge mode.  
Run AutoZ. 3.3.9  
Pressure applied is zero gauge  
but reading is NOT zero.  
Check measurement mode setting and  
set to gauge if gauge pressure  
measurements are desired. 3.3.3  
Current measurement mode is absolute and  
RPM4 is indicating atmospheric pressure.  
Operation is normal. Check  
Pressure applied is atmospheric  
but RPM4 indicates near zero.  
Current measurement mode is gauge and  
RPM4 is indicating zero gauge pressure.  
measurement mode setting and set to  
absolute if absolute pressure  
measurements are desired. 3.3.3  
A third Q-RPT designated HL is  
available but RPM4 has only two  
Q-RPTs.  
Parallel measurement mode has been  
activated.  
Operation is normal. Turn off parallel  
measurement mode if desired. 3.5.7.3  
NOT reading pressure applied to  
the test port and <SDS CLOSED>  
is flashing over the pressure  
indication.  
SDS is CLOSED for the active Q-RPT so the  
pressure applied to the test port is NOT  
getting to the Q-RPT.  
After taking precautions to assure that  
pressure applied to test port is safe for  
the RPT, OPEN SDS. 3.2.7, 3.3.8  
Familiarize yourself with your RPM4  
configuration. Connect pressure to be  
measured to correct TEST(+) port.  
2.3.5, 5.6  
RPM4 may have two TEST(+) ports and the  
pressure to be measured is connected to the  
wrong Q-RPT’s port  
Is NOT reading pressure applied  
to the TEST(+) port.  
RPM4 may have two TEST(+) ports and  
pressure to be measured is connected to  
correct port but active Q-RPT is NOT the  
Q-RPT on that TEST port.  
Familiarize yourself with your RPM4  
configuration. Select active range to be  
on the Q-RPT to which the pressure to  
be measured is corrected. 5.6, 3.3.1  
<SDS CLOSED> is displayed  
alternating with the measured  
pressure.  
Operation is normal. OPEN SDS if  
desired. 3.3.8  
SDS is CLOSED for the active Q-RPT.  
SDS should be present on a  
Q-RPT but does not seem to be  
active.  
SDS has been turned full time OFF for the  
Q-RPT.  
Turn SDS full time ON. 3.5.4.2  
When not in differential or parallel  
measurement mode, SDS on the inactive  
Q-RPT can only be OPENED using direct  
SDS control.  
SDS will not OPEN for the Q-RPT  
shown on the second line in the  
Q-RPT DISPLAY function.  
Use direct SDS direct control to OPEN  
SDS on the inactive Q-RPT. 3.5.4.1  
SDS was left OPEN on one  
Q-RPT when ranges were  
changed. When you come back  
to it, its CLOSED again.  
When changing ranges causes a change of  
the active Q-RPT, SDS is always CLOSED  
for the Q-RPT that becomes inactive.  
Operation is normal. 3.2.7  
You would like to eliminate the  
SDS function for a Q-RPT.  
Set SDS to be inactive except for an  
overpressure situation.  
Turn SDS full time OFF for the Q-RPT.  
3.5.4.2  
Page 133  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
NOTES  
© 2004-2007 DH Instruments, a Fluke Company  
Page 134  
7. APPENDIX  
7. APPENDIX  
7.1  
REMOTE [ENT]  
The RPM4 remote ENTER function operates by detecting the open or closed status of the REMOTE  
ENTER switch.  
The normal status of the ENTER switch is OPEN. When RPM4 detects a CLOSED condition held for 300 ms,  
it is interpreted as equivalent to a press of the [ENT] key.  
Any switch may be used to accomplish the remote ENTER function. The switch should be installed on  
the optional remote ENTER cable (DHI P/N 103128). Install the switch by connecting its two terminals to  
the black and white wires of the remote ENTER cable.  
Figure 10. Remote [ENT] Connector Schematic  
1. Black wire  
2. White wire  
Page 135  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
7.2  
UNIT CONVERSION  
7.2.1  
PRESSURE  
RPM4 performs all internal calculations in SI units. Numerical values input or output in other  
units are converted to SI immediately after entry and back to other units just before output as  
needed.  
Table 28 provides the conversion coefficients used by RPM4 to convert numerical values  
expressed in SI units to corresponding values expressed in other units.  
Table 28. Pressure Unit of Measure Conversion Coefficients  
TO CONVERT FROM Pa To  
Pascal  
MULTIPLY BY  
Pa  
1.0  
mbar  
millibar  
1.0 E-02  
hPa  
hecto Pascal  
1.0 E-02  
kPa  
kilo Pascal  
1.0 E-03  
bar  
Bar  
1.0 E-05  
mmWa @ 4°C  
mmHg @ 0°C  
psi  
millimeter of water  
millimeter of mercury  
pound per square inch  
pound per square foot  
inch of water  
1.019716 E-01  
7.50063 E-03  
1.450377 E-04  
1.007206 E-06  
4.014649 E-03  
4.021732 E-03  
4.018429 E-03  
2.953 E-04  
psf  
inWa @ 4°C  
inWa @ 20°C  
inWa @ 60°F  
inHg @ 0°C  
kcm2  
inch of water  
inch of water  
inch of mercury  
kilogram force per centimeter square  
milliTorr (micron of mercury  
Torr (millimeter of mercury)  
User  
1.019716 E-05  
7.50063  
mTorr  
Torr  
7.50063 E-3  
user  
User defined coefficient  
see Altitude Note below  
see Altitude Note below  
Ft  
feet of altitude  
M
meter of altitude  
Altitude Note:  
Quantities expressed in units of altitude follow MIL-STD-859A  
“Static Pressure, p, in Inches of Mercury for Values of Pressure Altitude, H,  
in Geopotential Feet.” MIL-STD-859A provides tables of pressure in inches of mercury  
as a function of altitude in feet. RPM4 uses a set of equations to model the  
pressure/altitude relationship. The worst case deviation between the MIL-STD-859A  
table and the calculated pressure is 0.0001 inches of mercury (0.3 Pa). The pressure  
quantity expressed in inches of mercury is converted to Pascal following Table 28 above.  
For altitude expressed in meters, meters are converted to feet using 1 m = 3.28084 ft.  
© 2004-2007 DH Instruments, a Fluke Company  
Page 136  
8. WARRANTY  
8. WARRANTY  
8.1  
OVERVIEW  
Except to the extent limited or otherwise provided herein, DH Instruments warrants for one year from  
purchase, each new product sold by it or one of its authorized distributors, only against defects in  
workmanship and/or materials under normal service and use. Products which have been changed or  
altered in any manner from their original design, or which are improperly or defectively installed, serviced  
or used are not covered by this warranty.  
DH Instruments and any of its Authorized Service Providers’ obligations with respect to this warranty are  
limited to the repair or replacement of defective products after their inspection and verification of such  
defects. All products to be considered for repair or replacement are to be returned to DH Instruments or  
its Authorized Service Provider after receiving authorization from DH Instruments or its Authorized  
Service Provider. The purchaser assumes all liability vis a vis third parties in respect of its acts or  
omissions involving use of the products. In no event shall DH Instruments be liable to purchaser for any  
unforeseeable or indirect damage, it being expressly stated that, for the purpose of this warranty, such  
indirect damage includes, but is not limited to, loss of production, profits, revenue, or goodwill,  
even if DH Instruments has been advised of the possibility thereof, and regardless of whether such  
products are used individually or as components in other products.  
The provisions of this warranty and limitation may not be modified in any respect except in writing signed  
by a duly authorized officer of DH Instruments  
The above warranty and the obligations and liability of DH Instruments and its Authorized Service  
Providers exclude any other warranties or liabilities of any kind.  
Table 29. DHI Authorized Service Providers  
DH INSTRUMENTS  
AUTHORIZED SERVICE PROVIDERS  
TELEPHONE,  
FAX & EMAIL  
NORMAL SUPPORT  
REGION  
COMPANY  
DH Instruments  
ADDRESS  
4765 East Beautiful Lane  
Phoenix AZ 85044-5318  
USA  
Tel 602.431.9100  
Fax 602.431.9559  
Worldwide  
Chrysantstraat 1  
3812 WX Amersfoort  
the NETHERLANDS  
Tel (+31) 33.46.22.000  
Fax (+31) 33.46.22.218  
European Union  
Japan/Asia  
Minerva Meettechniek B.V.  
258-1, Nakadai  
Kasumigaura-machi,  
Niihari-Gun,  
Tel 81/29.840.9111  
Fax 81/29.840.9100  
Ohte Giken, Inc.  
Technology Center  
Ibaraki 300-0133  
National Institute of Metrology  
Heat Division  
Pressure & Vacuum Lab  
NO. 18, Bei San Huan Donglu  
Beijing 100013  
Tel 010.64291994 ext 5  
Tel 010.64218637 ext 5  
Fax 010.64218703  
Peoples Republic of  
China  
DH Products Technical  
Service Division  
PR CHINA  
Page 137  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
NOTES  
© 2004-2007 DH Instruments, a Fluke Company  
Page 138  
9. GLOSSARY  
9. GLOSSARY  
A type of Q-RPT with a built-in vacuum reference that is intrinsically absolute (e.g. A10M).  
Axxx Q-RPTs support absolute, gauge and negative gauge measurement modes.  
Axxx  
Absolute Mode  
Active Q-RPT  
Measurement mode in which the Q-RPT indicates absolute pressure (difference from vacuum).  
The Q-RPT that is currently selected to be displayed on the top line of the RPM4  
display. Most function selections affect the active Q-RPT.  
A function that optimizes RPM4 measurement and control for a specific, user defined  
range of operation.  
AutoRange  
AutoRanged Range  
AutoTest or ATest  
AutoZero or AutoZ  
Barometer  
An RPM4 pressure measurement range created using the AutoRange function.  
RPM4 on-board automated testing sequences and their results.  
A process by which a Q-RPT and measurement mode is rezeroed (offset) relative to a standard.  
RPM4’s on-board atmospheric pressure measuring sensor. Also referred to as on-board barometer.  
A type of Q-RPT that is intrinsically gauge and is capable of operating bi-directionally,  
above and below atmosphere, through zero. BGxxx Q-RPTs support gauge and  
negative gauge measurement modes.  
BGxxx  
Default Range (DF)  
Deviation  
A Q-RPT’s maximum range that is always available using [RANGE] and cannot be deleted.  
A DISPLAY function in which the deviation of the current pressure from a target pressure  
is displayed.  
Device Under Test. The device or devices pneumatically connected to the RPM4  
TEST(+) port that the RPM4 is being used to test or calibrate.  
DUT  
Measurement mode in which the measured pressure is the different between the Hi and  
Lo Q-RPT (Hi – Lo).  
Differential mode  
Abbreviation of “full scale”. The full scale value is the maximum pressure of a measurement  
range. Limits and specifications are often expressed as % FS. Also see span.  
FS  
A type of Q-RPT that is intrinsically gauge but only measures pressure greater than  
atmosphere. Gxxx Q-RPTs support gauge measurement mode only.  
Gxxx  
Measurement mode in which the Q-RPT indicates gauge pressure (difference from  
atmospheric pressure), but only in the positive direction (above atmosphere).  
Gauge Mode  
Head  
A difference in height between the RPM4 reference level and the DUT.  
A DISPLAY function in which the highest and lowest pressure measurements since  
reset are recorded and displayed.  
HiLo  
The designation of a single Q-RPT in an RPM4, or, if there are two, the one that has the  
highest full scale default range.  
Hi Q-RPT  
HL Q-RPT  
The designation of the pseudo Q-RPT that results from the combination of using two  
Q-RPTs simultaneously in parallel measurement mode.  
In an RPM4 with two Q-RPTs, the Q-RPT that is not currently displayed on the top line  
of the display. The inactive Q-RPT may be displayed on the second line of the RPM4  
display using the RPT DISPLAY function.  
Inactive Q-RPT  
The designation of a the Q-RPT with the lower full scale default range in RPM4s with  
two Q-RPTs.  
Lo Q-RPT  
Whether pressure is being measured relative to absolute zero or vacuum (absolute mode)  
or relative to atmospheric pressure (gauge mode).  
Measurement Mode  
Measurement mode in which the Q-RPT indicates gauge pressure (difference from  
atmospheric pressure), in both positive and negative directions (above and below  
atmosphere).  
Negative gauge or  
compound gauge  
The difference between a Q-RPT reading and the AutoZero reference at the time AutoZ  
is run. Used by the AutoZ function when Auto Z is ON to compensate Q-RPT readings  
for changes in zero over time.  
Poffset  
AutoZero reference value. Value indicated by the device against which the Q-RPT is  
zeroed by AutoZ.  
Pstd,0  
PA  
Pressure adder, used to offset a Q-RPT or barometer to calibrate it.  
Page 139  
© 2004-2007 DH Instruments, a Fluke Company  
RPM4™ OPERATION AND MAINTENANCE MANUAL  
PM  
Pressure multiplier, used to adjust span of a Q-RPT or barometer to calibrate it.  
Operating mode of RPM4s with two Q-RPTs in which both Q-RPTs are used to measure  
together in parallel and the indicated pressure is the average of their readings. This  
creates a pseudo Q-RPT designated HL.  
Parallel Measurement  
Mode  
The maximum pressure limit of a Q-RPT. If the pressure measured by the Q-RPT  
exceeds Pmax!, an overpressure condition occurs.  
Pmax!  
PPC3  
Pressure controller calibrator manufactured by DHI. RPM4 can be used as an external  
reference device for a PPC3. PPC3 automates RPM4 pressure control.  
The transducer used by RPM4 for low uncertainty pressure measurement. May be  
designated as Hi, Lo or HL depending on its position and role in t he RPM4.  
Q-RPT  
(Quartz Reference  
Pressure Transducer)  
Q-RPTs are designated by a leading A, G or BG (absolute, gauge or bi-directional  
gauge) followed by three numbers and a letter indicating the maximum range of the  
Q-RPT in kPa (nnnK) or MPa (nnnM).  
A DISPLAY function in which the rate of change of pressure in pressure unit/second is  
displayed.  
Rate  
Front panel LED indication of when the pressure measured by RPM4’s active Q-RPT is  
stable within the stability limit. Leading character of the second line when the inactive Q-  
RPT is displayed on the second line in RPT DISPLAY mode.  
Ready/Not Ready  
RPT2x  
Parallel measurement mode in which both Q-RPTs of an RPM4 with two Q-RPTs are  
used together and the indicated pressure is the average of their measurements.  
SDS (Self Defense  
System)  
A system to protect Q-RPTs from overpressure made up of isolation and vent valves  
and internal operating logic. Applies only to Q-RPTs designated A7M or lower.  
The difference between FS and the lowest point in a range. For example, the span of a  
100 kPa FS range in negative gauge mode is nominally 200 kPa (from - 100 kPa to 100 kPa).  
Span  
A limit expressed in units of pressure per second (e.g., kPa/second). The stability limit is used  
as the Ready/Not Ready criterion. Ready if rate of change is less than stability limit.  
Not Ready if rate of change is greater than stability limit.  
Stability Limit  
Target  
The value from which deviations are measured in the Deviation DISPLAY function.  
A user settable maximum pressure limit. When pressure exceeds UL, RPM4 beeps  
intermittently. In negative gauge measurement mode, there is also a user settable lower limit.  
UL (Upper Limit)  
User Level  
QDUT  
Levels of security that can be set to protect certain RPM4 functions from being accessed.  
On-board automated test sequence that AutoRanges RPM4 based on characteristics of  
the Device Under Test (DUT).  
© 2004-2007 DH Instruments, a Fluke Company  
Page 140  

GE AHR50 User Manual
Gateway VX760 User Manual
Electrolux EHE 688 B User Manual
Diamond Systems Corporation Computer Hardware PR Z16 LC ST User Manual
DCS CP 364GL User Manual
Dacor AOCTK27 User Manual
Cypress Perform CY7C1382D User Manual
Black Box Computer Hardware ACXSFPC User Manual
Avocent OutLook 4160ES User Manual
Addonics Technologies JUPITER CIPHER EXDRIVE JCEDIF128 User Manual