Powerware Power Supply ST 2400S User Manual

Model ST-2400S  
Horsepower Computer System  
User Manual  
In the USA:  
Star Test Dynamometer, Inc.  
712 Thistlewood Court  
Normal, IL 61761  
Phone: (309) 826-1484  
In Mexico, Central & South America:  
Negociaciones Fuentes S.A. DE CV  
Av. La Luz 4549 Col. Cortijo del Rio  
Monterey, N.L. Mexico 64890  
Phone: 81.8349.1416  
Manufacturered by:  
Ries Labs, Inc.  
2275 Raven Road  
Farina, IL 62838  
Phone: (618) 238-1400  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Description:  
The function of the Model 2400S Horsepower Computer is to provide the operator with a  
continuous digital readout of the RPM, TORQUE, POWER (Horsepower or Kilowatts)  
and percentage of Torque Rise ( % TORQUE RISE) when properly attached to a  
compatible dynamometer.  
The RPM readout shows the operator the rotation speed (rotations per minute) of the  
power shaft of the dynamometer. The RPM is measured by a pickup and gear  
combination that is mounted on the dynamometer and coupled to the power shaft of the  
dynamometer.  
The TORQUE readout shows the operator the torque (Foot-Pounds or Newton-Meters)  
being produced by the prime mover being tested. This is the same as the torque applied  
to the dynamometer by the power source (motor, engine, drive wheels, etc.). The torque  
is measured by a load cell that is mounted on the dynamometer.  
The POWER readout shows the operator the amount of power being produced by the  
prime mover and applied to the dynamometer. This is the same as the power being  
absorbed by the dynamometer. It is computed by the Horsepower Computer using the  
RPM and Torque measurements using the formulae below:  
HORSEPOWER = ( RPM * TORQUE (foot-pounds) ) / 5252  
KILOWATTS = ( RPM * TORQUE (Newton-Meters)) / 9549  
The % Torque Rise (% Torque Load) meter shows the torque as a percentage compared  
to a reference torque value. It is used to measure the “lugging ability” of an engine.  
The Horsepower Computer has a RS-232 compatible serial interface which can be  
connected EITHER to compatible serial printer OR to an external computer system.  
When connected to a printer, the system may be used to provide a “hard copy” printout of  
measurement results. When connected to an external computer, the system may be used  
for printing, storing, graphing, (etc.) the measurements performed by the dynamometer  
system (including the dynamometer, horsepower computer, and external computer).  
Installation:  
The Model 2400S horsepower computer should be installed in a location where the unit is  
not exposed to wetness, extremely high temperatures, prolonged direct sunlight, or other  
environmental factors that would shorten the life expectancy of the unit.  
3
Download from Www.Somanuals.com. All Manuals Search And Download.  
Power Supply:  
The Model 2400S horsepower computer is normally operated from 110 to 125  
VAC (60 Hz) using the outlet mounted power supply that is supplied with the  
unit. The power consumption of the computer is very low and the unit has a very  
high tolerance for power supply variations, so nearly any standard 115 VAC  
utility power outlet should power the unit adequately. See (below) information on  
a special (optional) “wide-range” power supply which will power the unit  
properly when the line voltage is either very low or very high.  
The computer may also be operated from a source of 12 to 18 Volts DC such as a  
small DC power supply or 12 Volt storage battery. If a storage battery is used, be  
sure that it is properly charged. If the battery voltage is low, the POWER LED of  
the unit will flash “on” and “off” about once every second – indicating that the  
power supply voltage is inadequate to power the unit properly. NOTE: WHEN  
OPERATING THE UNIT FROM A BATTERY OR POWER SUPPLY,  
THE POLARITY (+/- WIRING) MUST BE CORRECT OR THE UNIT  
WILL NOT OPERATE. WIRING A BATTERY OR POWER SUPPLY TO  
THE UNIT WITH IMPROPER POLARITY MAY RESULT IN DAMAGE  
TO THE UNIT.  
Operation of the unit from a 110 to 250 VAC 50 to 60 Hz power source  
A special “universal input” power supply is available (as an option) which will  
allow the unit to be operated from a wide range of AC power sources – both  
domestic and international.  
This power supply has a detachable power cable which may be easily replaced  
with a power cable which matches the local power system.  
This power supply is also very useful when operating the unit from power  
sources which may be lower than standard and/or slightly erratic. This  
power supply will result in proper operation when the AC power source is a  
low as about 90 Volts AC.  
Operation:  
The horsepower computer normally operates with a two second measurement  
cycle. It can optionally be factory programmed for a one second measurement  
cycle. During the measurement cycle, the RPM of the dynamometer shaft is  
measured along with the torque sensed by the dynamometer load cell. At the end  
of each measurement cycle, the RPM and TORQUE values (averaged over the  
measurement interval) are displayed and the POWER and % TORQUE RISE  
4
Download from Www.Somanuals.com. All Manuals Search And Download.  
values are computed and displayed. This process is repeated continuously while  
the unit is in operation.  
Computer Function Switch:  
The computer function switch is used to turn the system power ON/OFF  
and to control the functional operation of the horsepower computer. The  
function switch has four positions ( “OFF”, “ZERO”, “CHECK”, and  
“RUN”).  
In the “OFF” position, the power to the horsepower computer (and the  
load cell, etc.) is turned “OFF”. The power is turned “ON” in the other  
three positions of the computer function switch.  
The horsepower computer has two user controllable self test modes  
(“ZERO” and “CHECK”). These can be used to test much of the  
horsepower computer’s internal circuits for proper operation. In the  
ZERO position, internal test signals are fed into the RPM and TORQUE  
measurement circuits. In the ZERO position of the function switch, these  
signals should result in readings of zero on all four displays. If the reading  
of any display remains substantially different from zero (more than +/- 1  
or 2 counts) when in the zero mode, some type of malfunction of the unit  
is indicated.  
The second user controllable test mode is the CHECK mode. In this  
mode, internal test signals are fed to the RPM and TORQUE measuring  
circuits to simulate normal operation of the unit at about 37.5 % of full  
scale torque. The actual readings shown on the displays of the unit depend  
on internal factory set optional settings – principally the full scale torque  
value (which corresponds to the size of the load cell being used with the  
unit). The RPM display should read about 4000 RPM (+/- 1 or 2 counts)  
on all units. The Torque display should read about 37.5 % of the load cell  
rating. Refer to the tables below for the proper readings of the Torque and  
Power displays for your unit. The Power reading should agree with the  
power you compute from the actual RPM and TORQUE readings (within  
+/- 1 or 2 counts) using the above formulae for the horsepower or  
kilowatts.  
Load Cell Rating (Ft.-Lbs.) Torque (Ft.-Lbs.)  
Power (HP)  
28.56  
57.10  
142.8  
285.6  
100  
37.50  
75.00  
187.5  
375.0  
750.0  
1875  
200  
500  
1,000  
2,000  
5,000  
571.0  
1428  
5
Download from Www.Somanuals.com. All Manuals Search And Download.  
10,000  
3750  
2856  
CHECK readings using Ft.-Lbs. & Horsepower  
6
Download from Www.Somanuals.com. All Manuals Search And Download.  
Load Cell Rating (Ft.-Lbs.) Torque (N-M)  
Power (KW)  
21.30  
42.60  
106.5  
213.0  
426.0  
1065  
2130  
100 (135.5 N-M)  
200 (271 N-M)  
50.84  
101.6  
254.2  
508.4  
1016  
2542  
5084  
500 (677.5 N-M)  
1,000 (1355 N-M)  
2,000 (2710 N-M)  
5,000 (6775 N-M)  
10,000 (13550 N-M)  
CHECK readings using Newton-Meters and Kilowatts  
The ZERO and CHECK positions of the computer function switch  
provide quick checks to determine whether the horsepower computer is  
operating properly. Proper readings indicate that the major portion of the  
computer is working correctly. Note that the Load Cell sensor circuits and  
the RPM pickup circuits are NOT tested in the ZERO and CHECK modes.  
With the dynamometer at rest and the computer function switch set to  
“RUN”, the speed and power displays should show zero (“0”). The torque  
display may show some small value --- typically less than +/- 3 Ft.-Lbs (4  
N-M). The % torque rise display reading depends on whether or not the  
reference torque has been set and if so, to what value – so the reading of  
this display should be ignored at this time. See also the section below.  
System Power LED:  
The system power LED (Light Emitting Diode) is located on the front  
panel of the unit, just to the left of the computer function switch.  
This green LED indicates that power is applied to the unit and the unit is  
turned “ON”.  
If this light is slowly flashing ON and OFF, this indicates that the power  
supplied to the unit is inadequate (voltage is too low or too un-steady) and  
that the readings produced by the unit are likely in-accurate as a result.  
Torque Set Switch:  
The reference torque set switch is located on the front panel of the unit –  
just to the right of the computer function switch. Your unit may (as an  
option) be equipped with a remote torque set switch. This switch is  
located remotely from the horsepower computer but functions the same as  
the torque set switch.  
7
Download from Www.Somanuals.com. All Manuals Search And Download.  
The torque set switch is used to set the torque reference which is used to  
compute the % Torque Rise reading. To set the torque reference, proceed  
as follows:  
Run the engine at it rated speed, loaded at rated power or torque output.  
This represents the 100% torque output condition for the engine.  
With the engine running at its rated speed and load, press the Torque Set  
switch momentarily. The reference torque value is now set to the rated  
engine 100% torque and the % Torque Rise display should now read 100.0  
(100%). All future measurements will now display the torque on the %  
Torque Rise meter as the percentage of the reference torque value. For  
example, if the % torque rise meter reads 75.0, this means that the current  
actual torque is 75.0% of the reference (or rated) torque.  
Printer / Computer Interface:  
The Model 2400S horsepower computer is equipped with a RS-232-C  
compatible serial interface. This interface can be used to operate a small  
serial printer to make “hard copy” printouts of test results. Alternately,  
this interface can be used to connect the horsepower computer to a  
Windows type personal computer for calibration setup and so that test  
results can be saved, printed using the PC’s printer, etc. The horsepower  
computer senses which type of device is connected to the serial interface  
(printer or computer) and operates the interface accordingly. It is NOT  
possible to connect a serial printer and a personal computer to the  
horsepower computer at the same time.  
The print rate controls (“Report Rate” and/or “Manual Print”) are used to  
select which measurements are printed or sent to the personal computer.  
These controls are located on the front panel of the unit, above the  
Computer Function switch. Your unit may (optionally) be equipped with  
a remote manual print switch – which functions the same as the manual  
print switch but which may be located remotely from the horsepower  
computer.  
The Report Rate switch is used to control the rate at which the unit prints  
test results. Various automatic rates are available, from one report every  
10 seconds up to one report every thirty minutes. There is also a “manual”  
position on this switch. In the manual position, the unit only makes a  
printout when the manual print switch is pressed (momentarily).  
The manual print switch can be used at all settings of the report rate  
switch. It is NOT necessary to set the report rate switch to manual in  
order to use the manual print switch (or the optional remote print switch)  
to trigger a print report.  
8
Download from Www.Somanuals.com. All Manuals Search And Download.  
When the horsepower computer is used with a companion personal  
computer, a standard (9 pin) RS-232-C extension cable is used to connect  
the two computers together. This extension cable is normally 10 feet long,  
but can be up to 50 feet long (and even longer if special “long range” RS-  
232-C extension cables are used). The print rate and manual print  
switches serve to notify the personal computer which measurements are to  
be saved (or printed) in much the same way they are used when a printer is  
attached to the horsepower computer.  
Software for the 2400S horsepower computer:  
There are several software programs for the 2400S horsepower computer. These  
include:  
Calibration Setup Software for the 2400S:  
HpcOptionsW32 is software for the 2400S horsepower computer  
which is used to prepare the 2400S for calibration. This is done so  
that the 2400S will “know” the details of the method you will use  
to check the torque calibration of the unit. This “factory setup” is  
normally performed on the 2400S by your dealer prior to delivery  
of the 2400S to you so won’t have to.  
If you change your calibration method or calibration tools, this  
program can be used to inform the 2400S of the changes so that  
subsequent torque calibrations will be accurate.  
If you use a NIST traceable calibration method, this program must  
be used periodically (each time the load cell and the 2000S  
horsepower computer are sent in to have their NIST calibrations  
checked) to inform the 2400S of any changes to the load cell  
calibration or the internal 2400S traceable shunt resistor  
calibration.  
HpcOptionsW32 is compatible with most Windows based  
computer systems including Win95, Win98, WinMe, Win2000 and  
WinXP.  
Data Recording Software for the 2400S (Dyno32):  
The Dyno32 software makes it easy to reproduce the 2400S  
horsepower displays on the screen of the personal computer for  
remote viewing, etc. There are also features for printing and  
recording (saving) your dyno measurements. Data printing and  
9
Download from Www.Somanuals.com. All Manuals Search And Download.  
recording can be controlled from the 2400S horsepower computer  
and / or using the personal computer’s keyboard or mouse.  
Recorded data can be printed on the PC’s printer and / or can be  
easily “imported” into Microsoft Excel (or other analysis  
programs) for further operations such as graphing, etc.  
Dyno32 is compatible with most Windows based computer  
systems including Win95, Win98, WinMe, Win2000 and WinXP.  
Data Recording and Graphing Software for the 2400S:  
DynoGraph software combines most of the features of Dyno32  
with a “built-in” storage, printing, and graphing capability to  
streamline the computerization of your dynamometer system.  
The DynoGraph software integrates the important Dyno data  
collection, display, storage, and printing functions into one easy to  
use program that helps you to maintain complete records of the  
measurements you take using your dynamometer system. It also  
creates professional reports of your measurements including  
graphs of the important parameters such as Torque vs. RPM,  
Power vs. RPM, etc  
Up to 100 measurement “points” can be included in one  
DynoGraph document. There is provision to include your  
company info (name, address, etc.) along with the important  
information about the device being measured (customer info,  
machine info, date and time of the measurements, etc.)  
DynoGraph software is compatible with most Windows computer  
systems including Win95, Win98, WinMe, Win2000 and WinXP.  
Calibration:  
The calibration of the Model 2400S horsepower computer should be  
checked at least once per year – or sooner if any doubts or questions arise  
as to whether the readings produced by the unit are within the accuracy  
specifications of the unit.  
The Model 2400S should also have its calibration checked if any of the  
following events occur:  
1.) The instrument has been dropped or otherwise mistreated.  
10  
Download from Www.Somanuals.com. All Manuals Search And Download.  
2.) The instrument has been moved (re-installed) from one dynamometer  
to another.  
3.) The load cell of the dynamometer has been replaced, overloaded,  
dropped or otherwise mistreated.  
4.) The power supply to the unit has been repaired or replaced.  
5.) Prior to any measurements that require especially high accuracy.  
6.) The instrument has been repaired, exchanged or replaced.  
IMPORTANT NOTE:  
The Model 2400S is a delicate instrument and should be treated accordingly. It  
should not be allowed to get wet, be exposed to excessive temperatures, dropped or  
subjected to excessive shock or vibration. It should only be used with an approved  
power supply.  
It contains no user serviceable parts and no attempt should be made to repair or  
modify the unit.  
If the unit is in need of repair, it should be returned to the dealer or directly to Ries  
Labs, Inc. for repair.  
When it becomes necessary to check the calibration of the unit, follow the  
procedure below.  
Calibration Procedure:  
The Model 2400S horsepower computer uses quick and easy “push-  
button” calibration methods and can be calibrated using a variety of  
methods. Be sure to use the one that is correct for your dynamometer  
system and the calibration tools that are available to you.  
Prior to attempting calibration, first verify that the 2400S is operating  
correctly using the ZERO and CHECK positions of the computer  
function switch. If the 2400S does not pass these checks, there is a  
problem with the unit and it should be repaired before any attempt is  
made to calibrate the unit.  
Calibration of the Model 2400S is a simple, two step process:  
1.) Set the ZERO calibration: The dynamometer should not be running  
and should be disconnected from the engine, tractor, motor, etc. The  
RPM reading should be exactly zero and the TORQUE reading should  
be fairly close to zero – especially if the unit has previously been  
calibrated to the load cell. If necessary, disconnect the load cell from  
11  
Download from Www.Somanuals.com. All Manuals Search And Download.  
the torque arm of the dynamometer to insure that there is no force  
being applied to the load cell (which would result in an inaccurate zero  
calibration). Remove the calibration access cover panel and set the  
calibration mode switch to the ZERO position. Also, be sure that  
the shunt resistor switch is set to the OFF position. At this time note  
that the RPM display of the unit should indicate “1111” and the  
POWER display should indicate “0000”. The TORQUE display  
indicates the TORQUE and should read near zero. If the torque  
indication is excessive (plus or minus), the POWER display will read  
“EEEE” – which indicates that the zero offset of the load cell is  
excessive and that the ZERO calibration cannot proceed (see  
calibration notes below). Otherwise, press and release the ENTER  
push-button switch to perform the zero calibration. At this point, the  
TORQUE display should indicate zero and the zero calibration  
procedure has been completed.  
2.) Set the TORQUE SPAN calibration: Apply the CALIBRATION  
TORQUE (see calibration torque notes below) to the unit and set the  
calibration mode switch to the SPAN position. At this point the  
RPM display should indicate “2222”, the POWER display should  
indicate “0000”, and the TORQUE display should indicate a value  
approximately equal to the CALIBRATION TORQUE. If the  
deviation between the torque reading and the calibration torque is  
excessive, the POWER display will read “EEEE” – indicating that the  
TORQUE SPAN calibration cannot proceed (see calibration notes  
below). Otherwise, press and release the ENTER push-button switch  
to perform the TORQUE SPAN calibration. Now the TORQUE  
display should indicate the value of the CALIBRATION TORQUE  
and the torque span calibration has been completed.  
3.) Resume normal operation: Set the calibration mode switch back to  
the OFF (center) position. This turns off calibration mode and  
restores the unit to normal operation. Be sure to return the shunt  
resistor switch to the OFF position (if you used it during the torque  
span calibration). Replace the calibration access cover panel. The unit  
has now been accurately calibrated.  
Calibration Procedure Notes:  
1. ZERO CALIBRATION cannot proceed. This problem occurs when the ZERO  
OFFSET is excessive – too large for the zero offset correction facility of the 2400S to  
correct. Check the following:  
1.1 Make sure that the load cell is properly connected to the 2400S horsepower  
computer. Inspect the cable for damage, especially at the load cell end and the  
connector end. Make sure the connector is securely fastened to the 2400S torque  
sensor connector.  
1.2 Make sure that the load has been completely removed from the load cell. “Rock”  
the drive shaft of the dynamometer CW and CCW slightly (applying a small  
12  
Download from Www.Somanuals.com. All Manuals Search And Download.  
positive and negative torque to the unit) and verify that the torque reading returns  
closely to the same value. A failure here indicates a likely problem with the  
dynamometer. Have the dynamometer checked by your dealer or dyno service  
person.  
1.3 Make sure that the load has been completely removed from the load cell.  
Disconnect the load cell from the torque arm of the dynamometer by removing  
the coupling fastener. If this does not correct the excessive zero offset a likely  
defective or damaged load cell is indicated. You should have the load cell  
checked by your dealer or dyno service person.  
1.4 Make sure that the shunt resistor switch is set to the OFF position.  
2. TORQUE SPAN CALIBRATION cannot proceed. This problem occurs when the  
torque reading is not sufficiently close to that expected from the CALIBRATION  
TORQUE value. Check the following:  
2.1 Check to be sure that the CALIBRATION TORQUE is the value expected by the  
2400S horsepower computer. The expected calibration torque value is normally  
programmed into the 2400S by your dealer to match the calibration value and method  
you will be using to check and adjust the calibration of your unit. You can check this  
by setting the calibration mode switch back to the OFF position while leaving the  
CALIBRATION TORQUE applied to the unit. The TORQUE display will now read  
the (approximate) torque you have applied. If this value is within about +/- 10% of  
the CALIBRATION TORQUE that you have applied, then it is likely that the value  
expected by the 2400S for the CALIBRATION TORQUE is different than the value  
you are using. Check with your dealer or dyno service person to determine the  
calibration torque you should be using or use the 2400S calibration setup software to  
re-program the 2400S to expect the calibration torque you are currently using.  
2.2 If the TORQUE display does not read (within +/- abut 10%) the torque that you  
have applied a possible defective or damaged load cell is indicated and may need to  
be repaired or replaced. Have your dealer or dyno service person assist you.  
Torque Calibration Notes:  
There are several methods which can be used to apply a calibration torque value to the  
2400S horsepower computer.  
1.) Dead Weight Test Fixture: This method uses a Torque Test Bar (dead weight  
test fixture) and one or more calibration weights. The torque test bar is attached  
to the torque arm of the dynamometer, being careful to align the position of the  
mark on the torque test bar with corresponding mark on the torque arm of the  
dynamometer. Then connect the test weight(s) onto the torque test bar at the  
indicated position, usually the 4 foot (1.210 meter) position. The torque produced  
by the torque test bar must be accurately known, the total weight of the test  
weights must be accurately known, and the horizontal distance from the center  
line of the dyno to the indicated position must be accurately known. If any of  
these three factors is not accurate, then the resulting calibration will not be  
accurate –and the result is in-accurate torque and power readings from the  
13  
Download from Www.Somanuals.com. All Manuals Search And Download.  
dynamometer. The calibration torque produced is equal to the sum of the torque  
produced by the Torque Test Bar itself plus the torque produced by the test  
weight(s) – which is equal to the total weight of the test weight(s) times the  
horizontal distance from the center line of the dyno to the position of the test  
weights. For example, assume the torque of the torque test bar itself is 17 Ft.-  
Lbs., the total weight is 100 Lbs. and the horizontal distance is 4.00 Ft. The  
calibration torque value produced by this setup is equal to 417 Ft.-Lbs. ( = 4.00  
Ft. * 100 Lbs. + 17 Ft.-Lbs.)  
2.) Shunt Resistor: The 2400S horsepower computer has an internal shunt resistor  
which can be used to check the torque span calibration. The 2400S can  
(optionally) be equipped with a precision shunt resistor which can be used to  
perform a NIST (National Institute of Standards and Time) traceable torque  
calibration. The “torque” introduced by the shunt resistor depends on the  
resistance value of the shunt resistor as well as the properties of the load cell. For  
the NIST traceable torque calibration to be accurate, both the shunt resistor value  
and the load cell must have NIST traceable calibrations which should be checked  
periodically. A 2400S horsepower computer without the precision shunt resistor  
is equipped with a 1% precision 45.3 K Ohm shunt resistor (not adequate for  
NIST traceable calibrations) which can be used for a quick and fairly accurate  
check on the torque calibration and the torque sensor circuits of the 2400S. After  
performing the calibration of the unit using the dead weight test fixture calibration  
method, remove the dead weight test fixture and set the Shunt Resistor Switch to  
ON. The shunt resistor will produce a torque reading that is (roughly) 2/3 of the  
full scale torque of the unit (i.e. about 3300 Ft.-Lbs. on a 5000 Ft.-Lbs. full scale  
2400S). More precise values are shown in the table below. The reading should  
be within +/- 2 or 3 % of the appropriate value from the table below. The  
tolerance derives from the +/- 1% tolerance of the 45.3 K Ohm shunt resistor plus  
the tolerance of the load cell (likely +/- 1 or 2 %). If the reading is not this close,  
you should double check the calibration and your procedure as a likely problem is  
indicated. If the reading is within the above limits, record its value. It can be  
used later for a quick check on your unit’s calibration as it should be stable over  
time and temperature to within +/- 0.25% or better.  
Full scale Torque (Ft.-Lbs.)  
45.3 K Ohm Shunt Resistor Torque  
100  
200  
500  
1,000  
2,000  
5,000  
10,000  
64.14  
128.3  
320.7  
641.4  
1283  
3207  
6414  
14  
Download from Www.Somanuals.com. All Manuals Search And Download.  
In Case of Difficulty:  
The following is a troubleshooting guide that will help you to resolve any problems that  
may arise.  
The Model 2400S Horsepower Computer contains no user serviceable parts. If it needs  
to be repaired you may return the unit to your dealer (who can also assist you with other  
repair problems such as problem diagnosis, replacement of the load cell, RPM pickup,  
other dynamometer repairs, etc.) or directly to:  
In the USA:  
STAR TEST DYNAMOMETER, INC.  
712 THISTLEWOOD COURT  
NORMAL, ILLINOIS 61761  
PHONE: (309) 826-1484  
In Mexico, Central & South America:  
Negociaciones Fuentes S.A. DE CV  
Av. La Luz 4549 Col. Cortijo del Rio  
Monterey, N.L. Mexico 64890  
Phone: 81.8349.1416  
You may also return the 2400S Horsepower Computer and its power supply directly to  
the manufacturer for repair:  
RIES LABS, INC.  
2275 RAVEN ROAD  
FARINA, ILLINOIS 62838  
PHONE: (618) 238-1400  
Be sure to include a written description of the problems you are having with the unit, the  
name and phone number of a person to call if we need to discuss your problem with you,  
and return shipping instructions. If the unit is out of warranty, please also include a  
repair order and information about how you want the repaired unit returned to you. Ries  
Labs, Inc. does not open commercial accounts (charge accounts) for repair work. Ries  
Labs, Inc. accepts electronic payments (credit card or otherwise) using PayPal. You can  
sign up for your PalPal account by visiting http://www.paypal.com/ Sending your  
payment via PalPal is FREE, EASY, QUICK and SAFE.  
Ries Labs, Inc. does not offer repair services for the other components of your  
dynamometer – only 2000S and 2400S horsepower computers, their power supply, and  
other items manufactured by Ries Labs, Inc.  
15  
Download from Www.Somanuals.com. All Manuals Search And Download.  
The following table is useful for you to determine that cause of any problems that you  
might be able to fix yourself.  
Problem  
Possible causes and remedies  
No indication on displays. There is likely no power to the unit. Check the power supply  
Power LED is not lit.  
to be sure it is plugged in. Check the fuse on the front panel  
of the unit. Replace ONLY with the correct ½ amp fuse. DO  
NOT use a slow blow or higher value fuse as this can result  
in severe damage to the unit.  
Power LED comes ON  
and OFF erratically  
Check to be sure the power supply is plugged in securely.  
Try another outlet. Make sure the power connector is  
fastened tightly to the front of the unit.  
Power LED flashes ON  
and OFF regularly  
Power supply voltage is too low. Check the power supply or  
battery. The supply voltage must be at least 12 Volts with  
low power supply “ripple” for the unit to operate properly.  
Power supply voltage may be too high. The power supply  
voltage should be less than 20 Volts DC or damage to the  
unit will occur. Send the 2400S for repairs if the unit blows  
fuses when the power supply voltage is less than 20 Volts  
DC. Use only the correct size ( ½ amp) and type (fast blow)  
fuse – or severe damage to the unit will likely occur.  
Check the RPM pickup on the dynamometer. Be sure that it  
is not loose. Check the wiring from the RPM pickup to the  
horsepower computer. Make sure the RPM sensor connector  
is tight. Have the horsepower computer checked.  
Unit blows fuses  
RPM display reads zero  
all the time, or is erratic  
Torque display reads –  
EEE or some other value  
all the time (or is erratic)  
Check the load cell on the dynamometer. Be sure that it is  
not loose. Check the cable between the load cell and the  
horsepower computer. Make sure the Torque Sensor  
connector is tight. The load cell may be bad and need to be  
replaced. Have the horsepower computer checked.  
Check the printer cable between the horsepower computer  
and the printer. Be sure both ends are tight in their  
respective connectors. Make sure the printer is plugged into  
a proper power source. Perform a “self test” on the printer to  
be sure it is working. Have the horsepower computer  
checked.  
Printer doesn’t work (or  
works erratically)  
Horsepower or Kilowatt  
readings are low or not  
correct  
Check the torque calibration. If Chassis dyno, the tires may  
be slipping on the dynamometer rolls – increase chain  
tension to obtain more “over center” action between tires  
and rolls. Excess speed often causes power losses. If farm  
tractor, the PTO clutch may be slipping (refer to the tractor  
repair manual). Engine may not be performing properly.  
Have the horsepower computer checked.  
RPM readings are  
inaccurate  
Operate the unit in the CHECK function. If the reading is  
not 4000 RPM, have the horsepower computer repaired. If  
the CHECK reading is 4000 RPM, check the RPM pickup  
16  
Download from Www.Somanuals.com. All Manuals Search And Download.  
and the RPM sensor gear. Make sure that they are not loose  
and that the runout of the RPM gear is not excessive. Check  
the RPM sensor connector to be sure that it is tight. Check  
the cable from the RPM pickup to the horsepower computer.  
Check the power supply to the horsepower computer. Have  
the horsepower computer checked.  
Torque readings are  
inaccurate  
Operate the unit using the ZERO and CHECK functions. If  
the readings do not agree with the tables above, unit needs  
to be repaired. Check the load cell mounting to be sure that  
it is not loose. Check the dynamometer to be sure that it is  
not in a bind. Check the torque calibration of the  
horsepower computer. Check the power supply to the  
horsepower computer. Have the horsepower computer  
checked.  
Residual Torque readings Pressure or force on the dynamometer absorption unit cradle  
are high when the  
dynamometer is stopped.  
may be causing the residual readings. Remove the load cell  
from the torque arm of the dyno to see if this removes the  
excessive residual torque reading. Manually rock the torque  
arm of the dyno. It should move freely and easily a  
minimum of 0.5 inches (12.7 mm) up and down. The load  
cell must be in a free floating position when not under load.  
Re-adjust the torque cable and connectors if necessary.  
Check the calibration zero of the horsepower computer.  
The load cell may be damaged and need to be replaced.  
Have the horsepower computer checked.  
17  
Download from Www.Somanuals.com. All Manuals Search And Download.  

Peavey Music Mixer X Eight RT User Manual
Peavey Stereo Equalizer RTD 215 User Manual
Philips CD Player AK 691 User Manual
Philips DVD Player MX2600 User Manual
Philips Indoor Furnishings P 8265 A User Manual
Philips Power Supply 3R12 User Manual
Philips Universal Remote G96SVCAA01 User Manual
Planar Computer Monitor PQ170 User Manual
Polaroid Flat Panel Television FLA 1911B User Manual
PYLE Audio Car Video System PL2DNTV7 User Manual