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SVM144-B
July, 2006
POWER MIG 255
For use with machines having Code Number : 10563, 10583,10986, 10990
Safety Depends on You
Lincoln arc welding and cutting
equipment is designed and built
with safety in mind. However,
your overall safety can be
increased by proper installation
. . . and thoughtful operation on
your part. DO NOT INSTALL,
OPERATE OR REPAIR THIS
EQUIPMENT WITHOUT READ-
ING THIS MANUAL AND THE
SAFETY PRECAUTIONS CON-
TAINED THROUGHOUT. And,
most importantly, think before
you act and be careful.
SERVICE MANUAL
Copyright © 2006 Lincoln Global Inc.
• World's Leader in Welding and Cutting Products •
• Sales and Service through Subsidiaries and Distributors Worldwide •
Cleveland, Ohio 44117-1199 U.S.A. TEL: 216.481.8100 FAX: 216.486.1751 WEB SITE: www.lincolnelectric.com
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ii
ii
SAFETY
ARC RAYS can burn.
ELECTRIC SHOCK can kill.
3.a. The electrode and work (or ground) circuits
are electrically “hot” when the welder is on.
Do not touch these “hot” parts with your bare
skin or wet clothing. Wear dry, hole-free
gloves to insulate hands.
4.a. Use a shield with the proper filter and cover
plates to protect your eyes from sparks and
the rays of the arc when welding or observing
open arc welding. Headshield and filter lens
should conform to ANSI Z87. I standards.
4.b. Use suitable clothing made from durable flame-resistant
material to protect your skin and that of your helpers from
the arc rays.
3.b. Insulate yourself from work and ground using dry insulation.
Make certain the insulation is large enough to cover your full
area of physical contact with work and ground.
4.c. Protect other nearby personnel with suitable, non-flammable
screening and/or warn them not to watch the arc nor expose
themselves to the arc rays or to hot spatter or metal.
In addition to the normal safety precautions, if welding
must be performed under electrically hazardous
conditions (in damp locations or while wearing wet
clothing; on metal structures such as floors, gratings or
scaffolds; when in cramped positions such as sitting,
kneeling or lying, if there is a high risk of unavoidable or
accidental contact with the workpiece or ground) use
the following equipment:
FUMES AND GASES
can be dangerous.
5.a. Welding may produce fumes and gases
hazardous to health. Avoid breathing these
• Semiautomatic DC Constant Voltage (Wire) Welder.
• DC Manual (Stick) Welder.
• AC Welder with Reduced Voltage Control.
fumes and gases.When welding, keep
your head out of the fume. Use enough
ventilation and/or exhaust at the arc to keep
3.c. In semiautomatic or automatic wire welding, the electrode,
electrode reel, welding head, nozzle or semiautomatic
welding gun are also electrically “hot”.
fumes and gases away from the breathing zone. When
welding with electrodes which require special
ventilation such as stainless or hard facing (see
instructions on container or MSDS) or on lead or
cadmium plated steel and other metals or coatings
which produce highly toxic fumes, keep exposure as
low as possible and below Threshold Limit Values (TLV)
using local exhaust or mechanical ventilation. In
confined spaces or in some circumstances, outdoors, a
respirator may be required. Additional precautions are
also required when welding on galvanized steel.
3.d. Always be sure the work cable makes a good electrical
connection with the metal being welded. The connection
should be as close as possible to the area being welded.
3.e. Ground the work or metal to be welded to a good electrical
(earth) ground.
3.f. Maintain the electrode holder, work clamp, welding cable and
welding machine in good, safe operating condition. Replace
damaged insulation.
5.b. Do not weld in locations near chlorinated hydrocarbon vapors
coming from degreasing, cleaning or spraying operations.
The heat and rays of the arc can react with solvent vapors to
form phosgene, a highly toxic gas, and other irritating prod-
ucts.
3.g. Never dip the electrode in water for cooling.
3.h. Never simultaneously touch electrically “hot” parts of
electrode holders connected to two welders because voltage
between the two can be the total of the open circuit voltage
of both welders.
5.c. Shielding gases used for arc welding can displace air and
cause injury or death. Always use enough ventilation,
especially in confined areas, to insure breathing air is safe.
3.i. When working above floor level, use a safety belt to protect
yourself from a fall should you get a shock.
5.d. Read and understand the manufacturer’s instructions for this
equipment and the consumables to be used, including the
material safety data sheet (MSDS) and follow your
employer’s safety practices. MSDS forms are available from
your welding distributor or from the manufacturer.
3.j. Also see Items 6.c. and 8.
5.e. Also see item 1.b.
Mar ‘95
LN-15
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iii
SAFETY
WELDING SPARKS can
cause fire or explosion.
CYLINDER may explode
if damaged.
6.a. Remove fire hazards from the welding area.
If this is not possible, cover them to prevent
7.a. Use only compressed gas cylinders
containing the correct shielding gas for the
the welding sparks from starting a fire.
Remember that welding sparks and hot
materials from welding can easily go through small cracks
and openings to adjacent areas. Avoid welding near
hydraulic lines. Have a fire extinguisher readily available.
process used and properly operating
regulators designed for the gas and
pressure used. All hoses, fittings, etc. should be suitable for
the application and maintained in good condition.
7.b. Always keep cylinders in an upright position securely
chained to an undercarriage or fixed support.
6.b. Where compressed gases are to be used at the job site,
special precautions should be used to prevent hazardous
situations. Refer to “Safety in Welding and Cutting” (ANSI
Standard Z49.1) and the operating information for the
equipment being used.
7.c. Cylinders should be located:
•Away from areas where they may be struck or subjected to
physical damage.
6.c. When not welding, make certain no part of the electrode
circuit is touching the work or ground. Accidental contact can
cause overheating and create a fire hazard.
•A safe distance from arc welding or cutting operations and
any other source of heat, sparks, or flame.
7.d. Never allow the electrode, electrode holder or any other
electrically “hot” parts to touch a cylinder.
6.d. Do not heat, cut or weld tanks, drums or containers until the
proper steps have been taken to insure that such procedures
will not cause flammable or toxic vapors from substances
inside. They can cause an explosion even though they have
been “cleaned”. For information, purchase “Recommended
Safe Practices for the Preparation for Welding and Cutting of
Containers and Piping That Have Held Hazardous
Substances”, AWS F4.1 from the American Welding Society
(see address above).
7.e. Keep your head and face away from the cylinder valve outlet
when opening the cylinder valve.
7.f. Valve protection caps should always be in place and hand
tight except when the cylinder is in use or connected for
use.
7.g. Read and follow the instructions on compressed gas
cylinders, associated equipment, and CGA publication P-l,
“Precautions for Safe Handling of Compressed Gases in
Cylinders,” available from the Compressed Gas Association
1235 Jefferson Davis Highway, Arlington, VA 22202.
6.e. Vent hollow castings or containers before heating, cutting or
welding. They may explode.
6.f. Sparks and spatter are thrown from the welding arc. Wear oil
free protective garments such as leather gloves, heavy shirt,
cuffless trousers, high shoes and a cap over your hair. Wear
ear plugs when welding out of position or in confined places.
Always wear safety glasses with side shields when in a
welding area.
FOR ELECTRICALLY
powered equipment.
6.g. Connect the work cable to the work as close to the welding
area as practical. Work cables connected to the building
framework or other locations away from the welding area
increase the possibility of the welding current passing
through lifting chains, crane cables or other alternate circuits.
This can create fire hazards or overheat lifting chains or
cables until they fail.
8.a. Turn off input power using the disconnect
switch at the fuse box before working on
the equipment.
8.b. Install equipment in accordance with the U.S. National
Electrical Code, all local codes and the manufacturer’s
recommendations.
6.h. Also see item 1.c.
8.c. Ground the equipment in accordance with the U.S. National
Electrical Code and the manufacturer’s recommendations.
Mar ‘95
POWER MIG 255
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iv
iv
SAFETY
zones où l’on pique le laitier.
PRÉCAUTIONS DE SÛRETÉ
6. Eloigner les matériaux inflammables ou les recouvrir afin de
prévenir tout risque d’incendie dû aux étincelles.
Pour votre propre protection lire et observer toutes les instructions
et les précautions de sûreté specifiques qui parraissent dans ce
manuel aussi bien que les précautions de sûreté générales suiv-
antes:
7. Quand on ne soude pas, poser la pince à une endroit isolé de
la masse. Un court-circuit accidental peut provoquer un
échauffement et un risque d’incendie.
Sûreté Pour Soudage A L’Arc
1. Protegez-vous contre la secousse électrique:
8. S’assurer que la masse est connectée le plus prés possible de
la zone de travail qu’il est pratique de le faire. Si on place la
masse sur la charpente de la construction ou d’autres endroits
éloignés de la zone de travail, on augmente le risque de voir
passer le courant de soudage par les chaines de levage,
câbles de grue, ou autres circuits. Cela peut provoquer des
risques d’incendie ou d’echauffement des chaines et des
câbles jusqu’à ce qu’ils se rompent.
a. Les circuits à l’électrode et à la piéce sont sous tension
quand la machine à souder est en marche. Eviter toujours
tout contact entre les parties sous tension et la peau nue
ou les vétements mouillés. Porter des gants secs et sans
trous pour isoler les mains.
b. Faire trés attention de bien s’isoler de la masse quand on
soude dans des endroits humides, ou sur un plancher met-
allique ou des grilles metalliques, principalement dans
les positions assis ou couché pour lesquelles une grande
partie du corps peut être en contact avec la masse.
c. Maintenir le porte-électrode, la pince de masse, le câble de
soudage et la machine à souder en bon et sûr état defonc-
tionnement.
9. Assurer une ventilation suffisante dans la zone de soudage.
Ceci est particuliérement important pour le soudage de tôles
galvanisées plombées, ou cadmiées ou tout autre métal qui
produit des fumeés toxiques.
10. Ne pas souder en présence de vapeurs de chlore provenant
d’opérations de dégraissage, nettoyage ou pistolage. La
chaleur ou les rayons de l’arc peuvent réagir avec les vapeurs
du solvant pour produire du phosgéne (gas fortement toxique)
ou autres produits irritants.
d.Ne jamais plonger le porte-électrode dans l’eau pour le
refroidir.
e. Ne jamais toucher simultanément les parties sous tension
des porte-électrodes connectés à deux machines à souder
parce que la tension entre les deux pinces peut être le total
de la tension à vide des deux machines.
11. Pour obtenir de plus amples renseignements sur la sûreté, voir
le code “Code for safety in welding and cutting” CSA Standard
W 117.2-1974.
f. Si on utilise la machine à souder comme une source de
courant pour soudage semi-automatique, ces precautions
pour le porte-électrode s’applicuent aussi au pistolet de
soudage.
2. Dans le cas de travail au dessus du niveau du sol, se protéger
contre les chutes dans le cas ou on recoit un choc. Ne jamais
enrouler le câble-électrode autour de n’importe quelle partie du
corps.
PRÉCAUTIONS DE SÛRETÉ POUR
LES MACHINES À SOUDER À
TRANSFORMATEUR ET À
REDRESSEUR
3. Un coup d’arc peut être plus sévère qu’un coup de soliel, donc:
a. Utiliser un bon masque avec un verre filtrant approprié ainsi
qu’un verre blanc afin de se protéger les yeux du rayon-
nement de l’arc et des projections quand on soude ou
quand on regarde l’arc.
1. Relier à la terre le chassis du poste conformement au code de
l’électricité et aux recommendations du fabricant. Le dispositif
de montage ou la piece à souder doit être branché à une
bonne mise à la terre.
b. Porter des vêtements convenables afin de protéger la peau
de soudeur et des aides contre le rayonnement de l‘arc.
c. Protéger l’autre personnel travaillant à proximité au
soudage à l’aide d’écrans appropriés et non-inflammables.
2. Autant que possible, I’installation et l’entretien du poste seront
effectués par un électricien qualifié.
4. Des gouttes de laitier en fusion sont émises de l’arc de
soudage. Se protéger avec des vêtements de protection libres
de l’huile, tels que les gants en cuir, chemise épaisse, pan-
talons sans revers, et chaussures montantes.
3. Avant de faires des travaux à l’interieur de poste, la debranch-
er à l’interrupteur à la boite de fusibles.
4. Garder tous les couvercles et dispositifs de sûreté à leur place.
5. Toujours porter des lunettes de sécurité dans la zone de
soudage. Utiliser des lunettes avec écrans lateraux dans les
POWER MIG 255
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MASTER TABLE OF CONTENTS FOR ALL SECTIONS
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
i-iv
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section A
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section B
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section C
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section D
Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section E
Troubleshooting and Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section F
Electrical Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section G
Parts Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P344 Series
POWER MIG 255
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Section A-1
Section A-1
TABLE OF CONTENTS
- INSTALLATION SECTION -
Installation ..............................................................................................................Section A
Technical Specifications...............................................................................................A-2
Safety Precautions .......................................................................................................A-3
Uncrating the POWER MIG 255...................................................................................A-3
Location........................................................................................................................A-3
Input Power, Grounding and Connection Diagrams....................................................A-3
Output Polarity Connections........................................................................................A-5
Gun and Cable Installation...........................................................................................A-6
Shielding Gas ...............................................................................................................A-6
X
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A-2
A-2
INSTALLATION
TECHNICAL SPECIFICATIONS – POWER MIG 255
INPUT – SINGLE PHASE ONLY
Standard Voltage/Frequency Input Current @ 200 Amp Rated Output Input Current @ 250 Amp Rated Output
208/230/60 Hz
41/37 Amps
50/46
230/460/575/60 Hz
41/20/16 Amps
50/24/19
RATED OUTPUT
Duty Cycle
40%
Amps
Volts at Rated Amperes
26 Volts
250 Amps
200 Amps
145 Amps
60%
100%
28 Volts
26 Volts
OUTPUT
Welding Current Range
(Continuous)
Maximum Open Circuit Voltage
Welding Voltage Range
30 – 300 Amps
40 Volts
10-28 Volts
RECOMMENDED INPUT WIRE AND FUSE SIZES
75°C Copper Wire
in Conduit
75°C Copper Wire
in Conduit
Input Ampere
Rating On
Nameplate
AWG (IEC) Sizes
(For lengths
AWG (IEC) Sizes
(For lengths
exceeding 100 ft)
Input Voltage/
Frequency (Hz)
Fuse or Breaker
Size (Super Lag)
up to 100 ft)
2
2
208/60
230/60
460/60
575/60
60
60
30
25
50
46
24
19
8 (10 mm )
6 (16 mm )
2
2
10 (6 mm )
8 (10 mm )
2
2
2
14 (2.5 mm )
12 (4 mm )
12 (4 mm )
2
14 (2.5 mm )
NOTE: Use #10 AWG Grounding Wire
PHYSICAL DIMENSIONS
Height
Width
Depth
Weight
31.79 in.
808 mm
18.88 in.
480 mm
38.78 in.
985 mm
220 Ibs
100 kg
WIRE SPEED RANGE
Wire Speed
50 – 700 IPM (1.27 – 17.8 m/minute)
POWER MIG 255
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A-3
A-3
INSTALLATION
Read entire installation section before starting
installation.
INPUT POWER, GROUNDING AND
CONNECTION DIAGRAMS
SAFETY PRECAUTIONS
WARNING
WARNING
ELECTRIC SHOCK can kill.
• Do not touch electrically live parts such as
output terminals or internal wiring.
ELECTRIC SHOCK can kill.
• Only qualified personnel should perform this
installation.
• All input power must be electrically discon-
nected before proceeding.
• Only personnel that have read and under-
stood the POWER MIG 255 Operating
Manual should install and operate this equip-
ment.
------------------------------------------------------------------------
1. Before starting the installation, check with the
local power company if there is any question
about whether your power supply is adequate for
the voltage, amperes, phase, and frequency spec-
ified on the welder nameplate. Also be sure the
planned installation will meet the U.S. National
Electrical Code and local code requirements. This
welder may be operated from a single phase line
or from one phase of a two or three phase line.
• Machine must be grounded per any national,
local or other applicable electrical codes.
• The POWER MIG power switch is to be in the
OFF position when installing work cable and
gun and when connecting other equipment.
------------------------------------------------------------------------
UNCRATING THE POWER MIG 255
2. Models that have multiple input voltages specified
on the nameplate (e.g. 208/230) are shipped con-
nected for the highest voltage. If the welder is to
be operated on lower voltage, it must be recon-
nected according to the instructions in Figure A.1
for dual voltage machines and Figure A.2 for
triple voltage machines.
Cut banding and lift off cardboard carton. Cut banding
holding the machine to the skid. Remove foam and cor-
rugated packing material. Untape accessories from
Gas Bottle Platform. Unscrew the two wood screws (at
the Gas Bottle Platform) holding the machine to the
skid. Roll the machine off the skid assembly.
WARNING
LOCATION
Make certain that the input power is electrically
disconnected before removing the screw on the
reconnect panel access cover.
Locate the welder in a dry location where there is free
circulation of clean air into the louvers in the back and
out the front. A location that minimizes the amount of
smoke and dirt drawn into the rear louvers reduces the
chance of dirt accumulation that can block air pas-
sages and cause overheating.
------------------------------------------------------------------------
POWER MIG 255
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A-4
A-4
INSTALLATION
FIGURE A.1 — DUAL VOLTAGE MACHINE INPUT CONNECTIONS.
3. The 208/230 volt 60 Hz model POWER MIG is
4. Using the instructions in Figure A.3, have a qual-
ified electrician connect the receptacle or cable to
the input power lines and the system ground per
the U.S. National Electrical Code and any applic-
able local codes. See Technical Specifications
at the beginning of this chapter for proper wire
sizes. For long runs over 100 feet, larger copper
wires should be used. Fuse the two hot lines with
super lag type fuses as shown in the following dia-
gram. The center contact in the receptacle is for
the grounding connection. A green wire in the
input cable connects this contact to the frame of
the welder. This ensures proper grounding of the
welder frame when the welder plug is inserted into
the receptacle.
shipped with a 10 ft. input cable and plug con-
nected to the welder. A matching receptacle is
supplied with the machine. Mount the receptacle
in a suitable location using the screws provided.
Be sure it can be reached by the plug on the input
cable attached to the welder. Mount with the
grounding terminal at the top to allow the power
cable to hang down without bending.
The 230/460/575 volt 60 Hz model is not
equipped with a plug, an input cable, or a
receptacle.
POWER MIG 255
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A-5
A-5
INSTALLATION
FIGURE A.2 — TRIPLE VOLTAGE MACHINE INPUT CONNECTIONS.
FIGURE A.3 — RECEPTACLE DIAGRAM.
OUTPUT POLARITY CONNECTIONS
CONNECT TO A SYSTEM
GROUNDING WIRE. SEE
THE UNITED STATES
NATIONAL ELECTRICAL
CODE AND/OR LOCAL
CODES FOR OTHER
The welder, as shipped from the factory, is connected
for electrode positive (+) polarity. This is the normal
polarity for GMA welding.
If negative (–) polarity is required, interchange the con-
nection of the two cables located in the wire drive com-
partment near the front panel. The electrode cable,
which is attached to the wire drive, is to be connected
to the negative (–) labeled terminal. The work lead,
which is attached to the work clamp, is to be connect-
ed to the positive (+) labeled terminal.
DETAILS AND MEANS FOR
PROPER GROUNDING.
CONNECT TO HOT WIRES
OF A THREE-WIRE, SINGLE
PHASE SYSTEM OR TO ONE
PHASE OF A TWO OR
THREE PHASE SYSTEM.
POWER MIG 255
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A-6
A-6
INSTALLATION
GUN AND CABLE INSTALLATION
WARNING
The Magnum 250L gun and cable provided with the
POWER MIG 255 is factory installed with a liner for
0.035-0.045 in. (0.9-1.2 mm) electrode and an 0.035
in. (0.9 mm) contact tip. Install the 0.045 tip (also pro-
vided) if this wire size is being used.
CYLINDER may explode if
damaged.
• Gas under pressure is explosive. Always keep
gas cylinders in an upright position and always
keep chained to undercarriage or stationary
support. See American National Standard Z-
49.1, “Safety in Welding and Cutting” pub-
lished by the American Welding Society.
WARNING
Turn the welder power switch off before installing
gun and cable.
------------------------------------------------------------------------
------------------------------------------------------------------------
3. Stand to one side away from the outlet and open
the cylinder valve for an instant. This blows away
any dust or dirt which may have accumulated in
the valve outlet.
1. Lay the cable out straight.
2. Unscrew knurled screw on the drive unit front end
(inside wire feed compartment) until tip of screw
no longer protrudes into gun opening as seen
from front of machine.
WARNING
Be sure to keep your face away from the valve out-
let when “cracking” the valve.
3. Insert the male end of gun cable into the female
casting through opening in front panel. Make sure
connector is fully inserted and tighten knurled
screw.
------------------------------------------------------------------------
4. Attach the flow regulator to the cylinder valve and
tighten the union nut(s) securely with a wrench.
NOTE: If connecting to 100% CO cylinder, insert
regulator adapter between regulator and cylinder
valve. If adapter is equipped with a plastic washer, be
2
4. Connect the gun trigger connector from the gun
and cable to the mating receptacle inside the
compartment located above the gun connection
made in item 3 above. Make sure that the key-
ways are aligned, insert and tighten retaining ring.
sure it is seated for connection to the CO cylinder.
2
5. Attach one end of the inlet gas hose to the outlet
fitting of the flow regulator, the other end to the
POWER MIG 255 rear fitting, and tighten the
union nuts securely with a wrench.
SHIELDING GAS
(For Gas Metal Arc Welding Processes)
6. Before opening the cylinder valve, turn the regu-
lator adjusting knob counterclockwise until the
adjusting spring pressure is released.
Customer must provide cylinder of appropriate type
shielding gas for the process being used.
A gas flow regulator, for CO or Argon blend gas, and
2
an inlet gas hose are factory provided with the POWER
MIG 255. Install the shielding gas supply as follows:
7. Standing to one side, open the cylinder valve
slowly a fraction of a turn. When the cylinder pres-
sure gauge pointer stops moving, open the valve
fully.
1. Set gas cylinder on rear platform of POWER MIG
255. Hook chain in place to secure cylinder to rear
of welder.
WARNING
2. Remove the cylinder cap. Inspect the cylinder
valves and regulator for damaged threads, dirt,
dust, oil or grease. Remove dust and dirt with a
clean cloth.
Never stand directly in front of or behind the flow
regulator when opening the cylinder valve. Always
stand to one side.
------------------------------------------------------------------------
DO NOT ATTACH THE REGULATOR IF OIL,
GREASE OR DAMAGE IS PRESENT! Inform
your gas supplier of this condition. Oil or grease
in the presence of high pressure oxygen is
explosive.
8. The flow regulator is adjustable. Adjust it to the
flow rate recommended for the procedure and
process being used before making the weld.
POWER MIG 255
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Section B-1
Section B-1
TABLE OF CONTENTS
- OPERATION SECTION -
Operation ................................................................................................................Section B
Product Description......................................................................................................B-3
Recommended Processes and Equipment..................................................................B-3
Welding Capability........................................................................................................B-3
Limitations ....................................................................................................................B-3
Description of Controls ................................................................................................B-4
Wire Drive Roll..............................................................................................................B-4
Wire Size Conversion Parts..........................................................................................B-4
Procedure for Changing Drive and Idle Roll Sets ........................................................B-5
Wire Reel Loading - Readi-Reels, Spools, or Coils .....................................................B-5
To Mount a 30 lb (14 kg) Readi-Reel Package
(Using the Molded Plastic K363-P Readi-Reel Adapter).......................................B-5
To Mount 10 to 44 lb (4.5-20 kg) Spools (12 in./300 mm Diameter)
or 14 lb (6 kg) Innershield Coils.............................................................................B-5
To Start the Welder.......................................................................................................B-6
Feeding Wire Electrode................................................................................................B-6
Idle Roll Pressure Setting.............................................................................................B-6
Setting Run-In Speed on Standard Power MIG Feeder ..............................................B-6
Fast or Slow Run-In Mode Selection (When Timer Option is not Installed)..........B-6
Instructions to Enter Slow Run-In..........................................................................B-6
Instructions to Enter Fast Run-In...........................................................................B-6
Making a Weld..............................................................................................................B-7
Avoiding Wire Feeding Problems.................................................................................B-7
Fan Control...................................................................................................................B-8
Input Line Voltage Protection.......................................................................................B-8
Wire Feed Overload Protection....................................................................................B-8
Welding Thermal Overload Protection .........................................................................B-8
Overcurrent Protection .................................................................................................B-8
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B-2
B-2
OPERATION
Read entire Operation section before
operating the POWER MIG 255.
WARNING
ELECTRIC SHOCK can kill.
• Do not touch electrically live parts
or electrode with skin or wet
clothing. Insulate yourself from
work and ground.
• Always wear dry insulating
gloves.
FUMES AND GASES can be
dangerous.
• Keep your head out of fumes.
• Use ventilation or exhaust to
remove fumes from breathing
zone.
WELDING
SPARKS
can
cause fire or explosion.
• Keep flammable material away.
• Do not weld on closed containers.
ARC RAYS can burn eyes and
skin.
• Wear eye, ear and body protec-
tion.
Observe all safety information throughout
this manual.
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B-3
B-3
OPERATION
PRODUCT DESCRIPTION
RECOMMENDED PROCESSES
AND EQUIPMENT
The POWER MIG™ 255 is a complete semiautomatic
constant voltage DC arc welding machine built to meet
NEMA specifications. It combines a constant voltage
power source and a constant speed wire feeder with a
microcomputer-based controller to form a reliable high-
performance welding system. A simple control scheme,
consisting of continuous full range voltage and wire
feed speed controls, provides versatility with ease of
use and accuracy.
The POWER MIG 255 is recommended for GMA
welding processes using 10 to 44 lb (4.5 to 20 kg)
®
2 in. (51 mm) I.D. spools or Readi-Reel coils (with
optional adapter) of 0.025 in. through 0.045 in.
(0.6 to 1.2 mm) solid steel, 0.035 in. (0.9 mm)
stainless, 3/64 in. (1.2 mm) aluminum and 0.045 in.
®
(1.2 mm) Outershield ; as well as 0.035 in. (0.9 mm)
®
and 0.045 in. (1.2 mm) Innershield self-shielding
electrodes.
Other features include a 2 in. (51 mm) O.D. wire reel
spindle with adjustable brake, an integral gas cylinder
The POWER MIG is factory equipped to feed
0.035 in. (0.9 mm) electrodes and provides tip, guide,
and drive rolls for 0.045 in. (1.2 mm) electrode. It also
includes a 200A, 60% duty cycle (or 250A, 40% duty
cycle) rated, 12 ft (3.6 m) GMAW gun and cable
assembly equipped for these wire sizes. Use of GMAW
processes requires a supply of shielding gas.
mounting undercarriage, an adjustable CO or Argon
2
blend flow regulator with cylinder pressure gauge and
inlet hose, a 12 ft (3.6 m) Magnum 250L GMAW gun
and cable with fixed (flush) nozzle, a 10 ft (3.0 m)
power cable with plug and mating receptacle, and a 10
ft (3.0 m) work cable with clamp.
An Optional Timer kit provides variable burnback con-
trol, a spot function, a selectable 4-step trigger inter-
lock and adjustable “Run In” for wire starting optimiza-
tion. Also optional are a Spool Gun Adapter kit, a Dual
Cylinder Mounting Kit and an Aluminum Feeding Kit for
push feeding with standard built in feeder.
WELDING CAPABILITY
The POWER MIG 255 is rated at 250 amps @ 26 volts,
at a 40% duty cycle based on a ten minute cycle time.
It is capable of higher duty cycles at lower output cur-
rents and capable of up to 300 Amps at lower duty
cycles.
LIMITATIONS
The POWER MIG 255 MAY NOT operate
satisfactorily if powered with a portable or in-plant
generating system.
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B-4
B-4
OPERATION
DESCRIPTION OF CONTROLS
WIRE DRIVE ROLL
Power ON/OFF Switch — Place the lever in the “ON”
position to energize the POWER MIG 255. When the
power is on, the red LED display lights illuminate.
The drive rolls installed with the POWER MIG each
have two grooves, both for 0.030-0.0035 in.
(0.8-0.9 mm) solid steel electrode. Drive roll size is indi-
cated by the stencilling on the exposed side of the drive
roll. If feeding problems occur, then the drive roll may
be reversed or changed. See Procedure for
Changing Drive Roll in this section. This information
also appears on the Procedure Decal on the door
inside the wire compartment. An additional drive roll set
is provided for 0.045 in. (1.2 mm) solid steel electrode,
packaged standard with each machine.
Voltage Control — This is a continuous control that
gives full range adjustment of power source output volt-
age. It can be adjusted while welding over its 10 to 28
volt range.
Wire Speed Control — This controls the wire feed
speed from 50 to 700 inches per minute (1.2 to
17.8 m/min). The wire speed control can be preset on
the dial to the setting specified on the Procedure Decal
located inside the wire compartment door. Wire speed
is not affected when changes are made in the voltage
control.
WIRE SIZE CONVERSION PARTS
The POWER MIG 255 is rated to feed 0.025 through
0.045 in. (0.6 to 1.2 mm) solid or cored electrode sizes.
The drive roll kits and Magnum 250L gun and cable
parts are available to feed different sizes and types of
electrodes. See Accessories section.
FIGURE B.1 — OPERATOR CONTROLS
WIRE SPEED
VOLTS
ON
LINCOLN
POWER MIG 255
ELECTRIC
OFF
POWER
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B-5
B-5
OPERATION
2 IN. O.D.
SPINDLE
PROCEDURE FOR CHANGING
DRIVE AND IDLE ROLL SETS
ADAPTER
RETAINING
SPRING
1. Turn off the power source.
2. Release the pressure on the idle roll by swinging
the adjustable pressure arm down toward the
back of the machine. Lift the cast idle roll assem-
bly and allow it to sit in an upright position.
BRAKE
HOLDING
PIN
RETAINING
COLLAR
GROOVES
3. Remove the outside wire guide retaining plate by
loosening the two large knurled screws.
READI-REEL
INSIDE
CAGE
WIRES
RELEASE
BAR
4. Twist the drive roll retaining mechanism to the
unlocked position.
7. Set one of the Readi-Reel inside cage wires on
the slot in the retaining spring tab.
FIGURE B.2 — READI-REEL INSTALLATION.
5. Wiggle both the metal idle and drive rolls off of
their plastic hubs.
8. Lower the Readi-Reel to depress the retaining
spring and align the other inside cage wires with
the grooves in the molded adapter.
6. Remove the inside wire guide plate.
7. Replace the drive and idle rolls and inside wire
guide with a set marked for the new wire size.
9. Slide cage all the way onto the adapter until the
retaining spring “pops up” fully.
NOTE: Be sure that the gun liner and contact tip are
also sized to match the selected wire size.
CAUTION
8. Manually feed the wire from the wire reel, over the
drive roll groove and through the wire guide and
then into the brass bushing of the gun and cable
assembly.
Check to be sure the retaining spring has fully returned
to the locking position and has securely locked the
Readi-Reel cage in place. The retaining spring must
rest on the cage, not on the welding
electrode.
------------------------------------------------------------------------
10. To remove Readi-Reel from adapter, depress
retaining spring tab with thumb while pulling the
Readi-Reel cage from the molded adapter with
both hands. Do not remove adapter from spindle.
9. Replace the outside wire guide retaining plate by
tightening the two large knurled screws.
Reposition the adjustable pressure arm to its orig-
inal position to apply pressure. Adjust pressure as
necessary.
WIRE REEL LOADING -
To Mount 10 to 44 lb (4.5-20 kg) Spools
(12 in./300 mm Diameter) or 14 lb
(6 kg) Innershield Coils:
READI-REELS, SPOOLS, OR COILS
To Mount a 30 lb (14 kg) Readi-Reel
Package (Using the Molded Plastic K363-P
Readi-Reel Adapter:)
(For 13-14 lb (6 kg) innershield coils, a K435 coil
adapter must be used).
1. Open the wire drive compartment door.
1. Open the wire drive compartment door.
2. Depress the release bar on the retaining collar
and remove it from the spindle. See Figure B.2.
2. Depress the release bar on the retaining collar
and remove it from the spindle.
3. Place the optional adapter on the spindle.
3. Place the spool on the spindle making certain the
spindle brake pin enters one of the holes in the
back side of the spool (Note: an arrow mark on the
spindle lines up with the brake holding pin to
assist in lining up a hole). Be certain the wire
comes off the reel in a direction that it can de-reel
from the top of the coil.
4. Re-install the retaining collar. Make sure that the
release bar “pops up” and that the collar retainers
fully engage the retaining ring groove on the
spindle.
5. Rotate the spindle and adapter so the retaining
spring is at the 12 o'clock position.
4. Re-install the retaining collar. Make sure that the
release bar “pops up” and that the collar retainers
fully engage the retaining ring groove on the
spindle.
6. Position the Readi-Reel so that it will rotate in a
direction when feeding so as to be de-reeled from
top of the coil.
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B-6
B-6
OPERATION
2. If the wire “birdnests”, jams, or breaks at the drive
roll, the idle roll pressure is too great. Back the
adjustment knob out 1/2 turn, run new wire
through gun, and repeat above steps.
TO START THE WELDER
Turn the Power Switch switch to ON. This lights the red
LED display lights. With the desired voltage and wire
speed selected, operate the gun trigger for welder out-
put and to energize the wire feed motor.
3. If the only result was drive roll slippage, loosen the
adjustment knob on the conductor plate and pull
the gun cable forward about 6 in. (15 cm). There
should be a slight waviness in the exposed wire. If
there is not waviness, the pressure is too low.
Tighten the adjustment knob 1/4 turn, reinstall the
gun cable and repeat the above steps.
FEEDING WIRE ELECTRODE
WARNING
When triggering, the electrode and drive mecha-
nism are electrically “hot” relative to work and
ground and remain “hot” several seconds after the
gun trigger is released.
------------------------------------------------------------------------
SETTING RUN-IN SPEED ON STAN-
DARD POWER MIG FEEDER
NOTE: Check that drive rolls, guide plates, and gun
parts are proper for the wire size and type being used.
Refer to Table C.1 in Accessories section.
FAST OR SLOW RUN-IN MODE SELECTION
(When Timer Option is not installed)
The POWER MIG 255 is factory set for fast run-in
mode where the wire feed will accelerate directly to the
preset wire feed speed when the gun trigger is closed.
1. Turn the Readi-Reel or spool until the free end of
the electrode is accessible.
2. While securely holding the electrode, cut off the
bent end and straighten the first six inches. (If the
electrode is not properly straightened, it may not
feed properly through the wire drive system.)
Slow run-in mode may also be selected, where it will
initially feed wire at 50 IPM until output current is
sensed or for 1.0 second, whichever occurs first. It will
then accelerate to the preset wire feed speed.
3. Release the pressure on the idle roll by swinging
the adjustable pressure arm down toward the
back of the machine. Lift the cast idle roll assem-
bly and allow it to sit in an upright position. Leave
the outer wire guide plate installed. Manually feed
the wire through the incoming guide bushing and
through the guide plates (over the drive roll
groove). Push a sufficient wire length to assure
that the wire has fed into the gun and cable
assembly without restriction. Reposition the
adjustable pressure arm to its original position to
apply pressure to the wire.
NOTE: See operating instructions for Timer Option Kit
if it is installed, as it provides its own run-in operation.
INSTRUCTIONS TO ENTER SLOW RUN-IN
1. Turn power OFF on front panel of POWER MIG
255.
2. Turn the wire feed speed dial fully counterclock-
wise to minimum.
3. With the gun trigger closed, turn the power ON at
the front panel of the POWER MIG 255.
4. Press gun trigger to feed the electrode wire
through the gun.
4. The display will read “SLO run”.
INSTRUCTIONS TO ENTER FAST RUN-IN
IDLE ROLL PRESSURE SETTING
1. Turn power OFF on front panel of POWER MIG
255.
The idle roll pressure adjustment knob is set at the fac-
tory at the #2 hash mark. This is an approximate set-
ting. The optimum idle roll pressure varies with type of
wire, wire diameter, surface conditions, lubrication, and
hardness. As a general rule, hard wires may require
greater pressure, and soft, or aluminum wire, may
require less pressure than the factory setting. The opti-
mum idle roll setting can be determined as follows:
2. Turn the wire feed speed dial fully clockwise to
maximum.
3. With the gun trigger closed, turn the power ON at
the front panel of the POWER MIG 255.
4. The display will read “FAS run”.
1. Press end of gun against a solid object that is
electrically isolated from the welder output and
press the gun trigger for several seconds.
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B-7
B-7
OPERATION
NOTE: Arc starting characteristics may be effected
when using the fast run-in mode since optimum start-
ing processes are being overridden.
5. If welding gas is to be used, turn on the gas sup-
ply and set the required flow rate (typically 25-35
CFH; 12-16 liters/min).
On the initial trigger closure at power up, no output
power or wire feed will be available until the trigger is
opened and reclosed, regardless of wire feed speed
dial setting.
6. When using innershield electrode, the gas nozzle
may be removed from the insulation on the end of
the gun and replaced with the gasless nozzle.
This will give improved visibility and eliminate the
possibility of the gas nozzle overheating.
It is not necessary to repeat either of the above proce-
dures each time the unit is powered up. The unit will
remember the run-in mode from the previous power
down and return you to that same state upon your next
power up. Therefore, you need only perform one of the
above procedures when you want to change the run-in
mode.
7. Connect work cable to metal to be welded. Work
clamp must make good electrical contact to the
work. The work must also be grounded as stated
in Arc Welding Safety Precautions.
WARNING
When using an open arc process, it is necessary
to use correct eye, head, and body protection.
------------------------------------------------------------------------
MAKING A WELD
1. Check that the electrode polarity is correct for the
process being used, then turn the power switch
ON.
8. Position electrode over joint. End of electrode
may be lightly touching the work.
2. Set desired arc voltage and wire speed for the
particular electrode wire, material type and thick-
ness, and gas (for GMAW) being used. Use the
Application Chart on the door inside the wire com-
partment as a quick reference for some common
welding procedures.
9. Lower welding helmet, close gun trigger, and
begin welding. Hold the gun so the contact tip to
work distance is about 3/8 in. (10 mm) [3/4 in.
(20 mm) for Outershield].
10. To stop welding, release the gun trigger and then
pull gun away from the work after arc goes out.
3. If Timer Kit is installed, select the desired mode as
described in Operating Instructions for Timer
Kit in the Accessories section. Refer to the
Accessories section for additional welding infor-
mation pertaining to Spot mode.
11. When no more welding is to be done, close valve
on gas cylinder (if used), momentarily operate gun
trigger to release gas pressure, and turn off
POWER MIG 255.
4. Press the trigger to feed the wire electrode
through the gun and cable and then cut the elec-
trode within approximately 3/8 in. (10 mm) of the
end of the contact tip [3/4 in. (20 mm)
AVOIDING WIRE FEEDING
PROBLEMS
®
Outershield ].
Wire feeding problems can be avoided by observing
the following gun handling procedures:
NOTE: If set for slow run-in when the trigger is pulled,
the wire feeder feeds wire at low speed regardless of
the set wire feed speed until the welding arc starts or 1
second has elapsed. This feature enhances starting
and makes it easier to set the stickout. The 1 second
limit permits high speed loading of the gun and cable.
To change run-in mode, see Setting Run-In Speed in
this section, if the Timer Kit is not installed, or Timer Kit
Operation section if installed.
1. Do not kink or pull cable around sharp corners.
2. Keep the gun cable as straight as possible when
welding or loading electrode through cable.
3. Do not allow dolly wheels or trucks to run over
cables.
4. Keep cable clean by following the maintenance
instructions.
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B-8
5. Use only clean, rust-free electrode. The Lincoln
B-8
OPERATION
WIRE FEED OVERLOAD
PROTECTION
electrodes have proper surface lubrication.
6. Replace contact tip when the arc starts to become
unstable or the contact tip end is fused or
deformed.
The POWER MIG has solid state overload protection
of the wire drive motor. If the motor becomes
overloaded, the protection circuitry turns off the wire
feed speed and gas solenoid. Check for proper size
tip, liner, and drive rolls, for any obstructions or bends
in the gun cable, and any other factors that would
impede the wire feeding. To resume welding, simply
pull the trigger. There is no circuit breaker to reset as
the protection is done with reliable solid state
electronics.
7. Keep wire reel spindle brake tension to minimum
required to prevent excess reel over-travel which
may cause wire “loop-offs” from coil.
8. Use proper drive rolls and wire drive idle roll pres-
sure for wire size and type being used.
FAN CONTROL
WELDING THERMAL
OVERLOAD PROTECTION
The fan is designed to come on automatically when a
weld arc is established. The fan will stay on for a mini-
mum of 6 minutes after the weld arc is terminated. The
fan will also stay on when the machine’s welding and
feeding are disabled during thermostatic over temper-
ature protection. (See Welding Thermal Overload
Protection.)
The POWER MIG 255 has built-in protective ther-
mostats that respond to excessive temperature. They
open the wire feed and welder output circuits if the
machine exceeds the maximum safe operating tem-
perature because of a frequent overload, or high ambi-
ent temperature plus overload. The thermostats auto-
matically reset when the temperature reaches a safe
operating level and welding and feeding are allowed
again, when gun is retriggered.
INPUT LINE VOLTAGE
PROTECTION
High Line Voltage — If the line voltage exceeds 125%
of rated input voltage, the output will be reduced to the
lower level to protect voltage rating of the capacitor
bank.
OVERCURRENT PROTECTION
The machine will automatically reduce the output if the
load on the machine exceeds 300 to 320 amperes.
This protects the welding power SCR’s from excessive
short circuit currents and from exceeding their temper-
ature rating before the thermostats can react.
Low Line Voltage — You may not be able to get max-
imum output from the machine if the line voltage is less
than rated input. The unit will continue to weld, but the
output may be less than what is set.
Welding Procedure Information
70
80
100
110
120
90
Note: See inside cover of machine for additional, commonly used welding procedure information.
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Section C-1
Section C-1
TABLE OF CONTENTS
- ACCESSORIES SECTION -
Accessories ............................................................................................................Section C
Drive Roll Kits ...............................................................................................................C-2
3/64 in. (1.2 mm) Aluminum Feeding Kit (K1703-1) .....................................................C-2
K363P Readi-Reel Adapter ..........................................................................................C-2
Dual Cylinder Mounting Kit (K1702-1)..........................................................................C-2
Alternative Magnum GMAW Gun and Cable Assemblies............................................C-2
Magnum Gun Connection Kit (Optional K466-6) .........................................................C-2
Timer Kit Installation (Optional K1701-1) .....................................................................C-2
Operating Instructions for Timer Kit.......................................................................C-3
Spool Gun Adapter Kit (K1700-1) (Included in the K1692-1).......................................C-4
Making a Weld with the Spool Gun, Spool Gun (K1692-1) Installed.....................C-4
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C-2
C-2
ACCESSORIES
DRIVE ROLL KITS
ALTERNATIVE MAGNUM GMAW
GUN AND CABLE ASSEMBLIES
Refer to Table C.1 for various drive roll kits that are
available for the POWER MIG. All items in Bold are
supplied standard with the POWER MIG.
The following Magnum 250L gun and cable assemblies
are separately available for use with the POWER MIG
255. Each is rated 200 amps 60% duty cycle (or 250
amps 40% duty) and is equipped with the integrated
connector, twist-lock trigger connector, fixed nozzle
and insulator, and includes a liner, diffuser, and contact
tips for the wire sizes specified:
TABLE C.1 — AVAILABLE DRIVE ROLL KITS.
Wire
Size
Drive Roll Kit
0
.023-0.030 in. (0.6-0.8 mm) KP1696-030S
Solid
Steel
0.035 in. (0.9 mm)
0.045 in. (1.2 mm)
KP1696-035S
KP1696-045S
English Wire
Size
Metric Wire
Size
Length
Part No.
10 ft (3.0 m) K533-1
*12 ft (3.6 m) K533-7
15 ft (4.5 m) K533-3
0.035 in. (0.9 mm)
0.045 in. (1.2 mm)
KP1697-035C
KP1697-045C
Cored
0.035 – 0.045 in. 0.9 – 1.2 mm
*Fixed Nozzle
Aluminum
3/64 in. (1.2 mm)
KP1695-3/64A
MAGNUM GUN CONNECTION KIT
(Optional K466-6)
3/64 in. (1.2 mm) ALUMINUM
FEEDING KIT (K1703-1)
Using the optional K466-6 Magnum Connection Kit for
the POWER MIG permits use of standard Magnum
200, 300 or 400 gun and cable assemblies.
This kit helps push feeding aluminum through standard
machine feeder and gun. It provides gun and wire drive
conversion parts to weld with 3/64 in.
(1.2 mm) aluminum wire. 5356 alloy aluminum wire is
recommended for best push feeding performance.
TIMER KIT INSTALLATION
(Optional K1701-1)
Kit includes drive rolls and wire guide plate for the wire
drive, liner and two contact tips for the gun, along with
installation instructions.
The timer kit adds selectable 4-step trigger interlock,
spot and Run-In functions and manual adjustment of
burnback time. Install as follows, or per the instructions
included with the kit:
K363P READI-REEL ADAPTER
WARNING
The K363P Readi-Reel adapter mounts to the
2 in. spindle. It is needed to mount the 22-30 lb Readi-
Reels.
Remove all input power to the POWER MIG 255
before proceeding.
------------------------------------------------------------------------
1. Verify that the following items have been included
in the kit:
DUAL CYLINDER
MOUNTING KIT (K1702-1)
a. Timer board with harness and panel
assembly.
Permits stable side-by-side mounting of two full size (9
in. dia. x 5 ft. high) gas cylinders with “no lift” loading.
Simple installation and easy instructions provided.
Includes upper and lower cylinder supports, wheel
axles and mounting hardware.
b. Two screws.
2. Turn the power switch off and disconnect power
from the machine to prepare for kit installation.
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C-3
3. Using a screwdriver, remove the two screws
C-3
ACCESSORIES
3. Spot Weld Mode is used for tack welding parts
into position or for spot plug welds to hold thin
sheet metal together prior to manual stitch or con-
tinuous welding. To use this feature, adjust the
On-Time (0-5 seconds) as appropriate to obtain
the desired results. Closing the trigger initiates a
single timed spot weld cycle. Plug welds are made
by using a punch to make a 3/16 in. (5 mm) diam-
eter hole in the top sheet and arc welding through
the hole into the back sheet.
securing the lower cover panel to the front of the
machine. Remove the lower cover panel.
4. Attach the rectangular 10-pin plug connector on
the timer kit wiring harness to the mating recepta-
cle connector located directly behind the removed
cover panel. Be sure that the latch on the connec-
tor is aligned with the one on the board and insert
it until the latch engages.
5. Align the timer panel for installation and carefully
insert the printed circuit board and wiring harness
through the opening. Make sure the wiring har-
ness is not pinched between panels or between
printed circuit board and front panel cover.
To make spot plug welds, punch 3/16 in. (5 mm)
holes in the top sheet. Set the Spot Time control
to approximately 1.2 seconds and set the proce-
dure for the metal thickness to be welded. Install
spot weld nozzle (if available) on gun and press it
against the top sheet so the top and bottom
sheets are tight together. Close trigger and hold it
closed until the arc goes out. If a spot weld nozzle
is not used, smoother welds will result by moving
the welding wire in a small circle during the weld.
6. Secure the timer assembly with either the two
supplied screws or with the original screws. The
installation is now complete. Refer to the following
section for operating instructions.
4. Burnback Time control provides manual adjust-
ment of the burnback time (0-250 milliseconds) for
any selected welding mode. This control should
be set as low as possible without the wire “stick-
ing” in the puddle after each weld. Too long of a
burnback time may form a “ball” on the end of the
wire, or may “flash back” to the gun tip.
OPERATING INSTRUCTIONS
FOR TIMER KIT
If the optional Timer Kit (K1701-1) is installed, select
the desired mode with the selector switch:
1. Normal Welding mode provides weld power only
while the trigger switch is depressed. This is the
same operation as when the Timer Kit is not
installed.
5. Run-In Mode is used to adjust the starting wire
feed speed. Starting conditions for certain welding
applications can be improved with adjustment to
the Run-In speed. The control allows for initial
starting speeds from 50 to 150 IPM. After the arc
is started, the set point on the wire feed speed
control will dominate. Note that the Run-in is not
functional with the spool gun. Also note that if
Run-in is set fully counterclockwise to OFF, Run-
in speed will equal the preset WFS on the
machine.
2. 4-Step Trigger interlock mode eliminates the
need to hold the gun trigger while welding. It oper-
ates in 4 steps:
a. Close trigger and establish welding arc.
b. Release trigger and continue welding.
c. Reclose trigger near end of weld.
d. Release trigger again to stop welding.
If the arc is broken while using this feature, the
machine will reset to the “trigger off” condition
automatically.
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C-4
C-4
ACCESSORIES
SPOOL GUN ADAPTER KIT
WARNING
Remove all input power to the POWER MIG 255
before proceeding.
------------------------------------------------------------------------
The Spool Gun Adapter Kit provides direct connection
and use of the Spool Gun (with remote speed control)
with the POWER MIG 255 wire feed welder.
1.Pulling the trigger for the built-in feeder gun:
a. Disables spool gun operation.
b. Closing feeder gun trigger starts feeder gun
welding and makes both electrodes electri-
cally “HOT”.
It also provides gun trigger switch transfer between the
machine’s use with its feeder gun or the spool gun for
same polarity welding with different wire and gas
processes.
2. Pulling SPOOL GUN Trigger:
a. Disables built-in feeder gun operation.
The kit includes a spool gun adapter module assembly
with a single connecting plug, a rear gas inlet setting
with hose and mounting hardware with installation and
operation instructions.
b. Closing spool gun trigger starts spool gun
welding and makes both electrodes electri-
cally “HOT”.
3. Operation with POWER MIG 255:
®
K2297-1
Prince XL Spool Gun with Adaptor Included
K2310-1* Power MIG 255 Spool Gun Adaptor Kit
a. Turn the POWER MIG-255 input power
ON.
®
(connects Magnum SG Spool Gun OR
®
Prince XL Spool Gun
b. Adjust the voltage control to increase or
decrease your welding voltage.
K487-25
®
Magnum SG Spool Gun (requires K2310-
1 Adaptor Kit
c. Adjust the wire speed control on the spool
gun to increase or decrease the spool gun
wire feed speed.
*This kit can only be configured to run a Magnum® SG
Spool Gun OR a Prince® XL Spool Gun at a time; kit is
shipped configured for the Magnum® SG Spool Gun.
Wire Dia.
In. (mm)
WFS Setting
Spool Gun
Arc Voltage
Setting
0.030 in. (0.8 mm)
0.035 in. (0.9 mm)
3/64 in. (1.2 mm)
270
250
240
15V
16V
20V
MAKING A WELD WITH THE SPOOL GUN,
SPOOL GUN INSTALLED
The POWER MIG control circuitry is designed to
sense either the spool gun (built in) wire feeder trigger
circuitry. After the spool gun adapter kit has been
installed, the spool gun can easily be plugged in and
will be ready to use.
4. The following procedure settings for Aluminum
4043 can be used as initial settings for making
test welds to determine final settings:
5. To return to normal POWER MIG 255 welding
release the spool gun trigger and reset feeder
gun voltage procedure setting if necessary.
CAUTION
Closing either gun trigger will cause the electrode of
both guns to be electrically “HOT”. Be sure unused gun
is positioned so electrode or tip will not contact metal
case or other metal common to work.
6. Operation with Timer Option Kit (K1701-1)
installed in Power MIG 255:
All Timer Option Kit functions, except Run-in,
are functional with the spool gun. (See operat-
ing instructions for Timer Option Kit.
POWER MIG 255
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Section D-1
Section D-1
TABLE OF CONTENTS
- MAINTENANCE SECTION -
Maintenance...........................................................................................................Section D
Safety Precautions ........................................................................................................D-2
Routine and Periodic Maintenance...............................................................................D-2
Drive Rolls and Guide Tubes.........................................................................................D-2
Cable Cleaning ..............................................................................................................D-2
Gun Tubes and Nozzles ................................................................................................D-2
Contact Tip and Gas Nozzle Installation.......................................................................D-4
Liner Removal and Replacement ..................................................................................D-4
Liner Removal, Installation, and Trimming Instructions for Magnum 250L ..................D-4
Gun Handle Disassembly..............................................................................................D-5
Accessories and Expendable Replacement Parts for Magnum 250L Gun and Cable Assemblies............D-6
POWER MIG 255
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D-2
D-2
MAINTENANCE
SAFETY PRECAUTIONS
WARNING
DRIVE ROLLS AND GUIDE TUBES
After every coil of wire, inspect the wire drive mecha-
nism. Clean it as necessary by blowing with low pres-
sure compressed air. Do not use solvents for cleaning
the idle roll because it may wash the lubricant out of
the bearing. All drive rolls are stamped with the wire
sizes they will feed. If a wire size other than that
stamped on the roll is used, the drive roll must be
changed.
• Have a qualified electrician do the maintenance
and troubleshooting work.
• Disconnect the input power off using the dis-
connect switch at the main input supply before
working inside machine.
• Unplug the power cable if it is connected to a
receptacle.
------------------------------------------------------------------------
CABLE CLEANING
Clean the cable liner after using approximately 300
pounds (136 kg) of electrode.
Read the Safety Precautions in the front of this manu-
al before working on this machine.
1. Remove the cable from the wire feeder and lay it
out straight on the floor.
ROUTINE AND PERIODIC
MAINTENANCE
2. Remove the contact tip from the gun.
3. With an air hose at the gas diffuser end, use low
pressure to gently blow out the cable liner.
1. Disconnect input AC power supply lines to the
machine before performing periodic maintenance,
tightening, cleaning, or replacing parts.
CAUTION
Perform the following daily:
Excessive pressure at the start may cause the dirt to
form a plug.
------------------------------------------------------------------------
1. Check that no combustible materials are in the
welding or cutting area or around the machine.
4. Flex the cable over its entire length and again blow
out the cable.
2. Remove any debris, dust, dirt, or materials that
could block the air flow to the machine.
5. Repeat this procedure until no more dirt comes
out.
3. Inspect the electrode cables for any slits, punc-
tures in the cable jacket, or any condition that
would affect the proper operation of the machine.
GUN TUBES AND NOZZLES
Perform Periodically:
1. Replace worn contact tips as required.
Clean the inside of the machine with low pressure air
stream. Clean the following parts. Refer to Figure D.1.
2. Remove spatter from the inside of the gas nozzle
and tip every 10 minutes of arc time or as required.
Main transformer and output choke.
Power enhancement choke.
Wire drive assembly.
Capacitor bank.
SCR rectifier bridge and heat sink fins.
Fan motor assembly.
Control printed circuit board.
Snubber printed circuit board.
NOTE: The fan motor has sealed bearings which
require no maintenance.
POWER MIG 255
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D-3
D-3
MAINTENANCE
FIGURE D.1 — COMPONENT LOCATIONS.
FAN
MOTOR
ASSEMBLY
CONTROL PC
BOARD
SNUBBER
PC BOARD
WIRE DRIVE
ASSEMBLY
SCR
RECTIFIER
BRIDGE
OUTPUT
CHOKE
CAPACITOR
BANK
MAIN
TRANSFORMER
POWER
ENHANCEMENT
CHOKE
POWER MIG 255
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D-4
D-4
MAINTENANCE
CONTACT TIP AND GAS
NOZZLE INSTALLATION
LINER REMOVAL, INSTALLATION,
AND TRIMMING INSTRUCTIONS
FOR MAGNUM 250L
1. Choose the correct size contact tip for the elec-
trode being used (wire size is stenciled on the side
of the contact tip) and screw it snugly into the gas
diffuser.
NOTE: The variation in cable lengths prevents the
interchangeability of liners between guns. Once a liner
has been cut for a particular gun, it should not be
installed in another gun unless it can meet the liner cut
off length requirement. Liners are shipped with the
jacket of the liner extended the proper amount.
a. Be sure the nozzle insulator is fully screwed
onto the gun tube and does not block the gas
holes in the diffuser.
1. Remove the gas nozzle and nozzle insulator. See
Figure D.2.
2. Slip or screw the appropriate gas nozzle onto the
nozzle insulator.
2. Locate the set screw in the gas diffuser which is
used to hold the old liner in place.
NOTE: Either a standard 0.50 in. (12.7 mm) or option-
al 0.62 in. (15.9 mm) I.D. slip-on gas nozzle may be
used and should be selected based on the welding
application.
3. Loosen the set screw with a 5/64 in. (2.0 mm) Allen
wrench.
4. Remove the gas diffuser from the gun tube.
3. Adjust the gas nozzle as appropriate for the
GMAW process to be used.
5. Lay the gun and cable out straight on a flat surface.
6. Loosen the set screw located in the brass cable
connector at the feeder end of the cable and pull
the liner out of the cable.
a. Typically, the contact tip end should be flush
to extended 0.12 in. (3.2 mm) for the short-
circuiting transfer process and recessed 0.12
in. (3.2 mm) for spray transfer.
7. Insert a new untrimmed liner into the connector
end of the cable.
a. Check the liner bushing stencil to make sure
it is the appropriate one for the wire size being
used.
LINER REMOVAL AND
REPLACEMENT
NOTE: When you change wire size, a replacement
gas diffuser is required. Use the table below to select
the proper diffuser so the liner is held securely in place.
8. Fully seat the liner bushing into the connector.
Replacement
Liner
Part Number
Size Stenciled on
Fixed Nozzle Gas
Diffuser Part No.
(and Stencil)
Adjustable Nozzle
Gas Diffuser Part
No. (and Stencil)
Diameter of
Electrodes Used
End of Liner
Bushing
0.025-0.030 in. Steel
(0.6-0.8 mm)
KP1934-2
KP1934-1
KP1955-1
0.030 in. (0.8 mm)
0.045 in. (1.2 mm)
3/64 in. (1.2 mm)
KP2026-3
KP2026-3
KP2026-3
KP2026-2
KP2026-1B1
KP2026-1B1
0.035-0.045 in. Steel
(0.9-1.2 mm)
3/64 in. Aluminum
(1.2 mm)
POWER MIG 255
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D-5
9. Tighten the setscrew on the brass cable
D-5
MAINTENANCE
GUN HANDLE DISASSEMBLY
connector.
The internal parts of the gun handle may be inspected
or serviced if necessary.
NOTE: Do not install the gas diffuser onto the end of
the gun tube at this time.
10. Straighten the cable with the gas nozzle and noz-
zle insulator removed from the gun tube.
The gun handle consists of two halves that are held
together with a collar on each end.
11. Trim the liner to the length shown in Figure D.2.
To open up the handle:
1. Turn the collars approximately 60 degrees coun-
terclockwise (the same direction as removing a
right hand thread) until the collar reaches a stop.
FIGURE D.2 — LINER MAINTENANCE.
SET
BRASS CABLE
CONNECTOR
SCREW
2. Pull the collar off the gun handle.
NOTE: If the collars are difficult to turn, position the
gun handle against a corner, place a screwdriver
against the tab on the collar and give the screwdriver a
sharp blow to turn the collar past an internal locking rib.
See Figure D.3.
1-1/4" (1.25)
(31.8MM)
LINER TRIM
LENGTH
FIGURE D.3 — GUN HANDLE DISASSEMBLY.
GAS DIFFUSER
NOZZLE INSULATOR
GAS NOZZLE
12. Remove any burrs from the end of the liner.
13. Screw the gas diffuser onto the end of the gun tube
and tighten.
NOTE: Be sure the gas diffuser is correct for the liner
being used. (See table and diffuser stencil.)
14. Slightly tighten the set screw in the side of the gas
diffuser against the cable liner using 5/64 in.
(2.0 mm) Allen wrench.
CAUTION
This screw should only be gently tightened. Over tight-
ening will split or collapse the liner and cause poor wire
feeding.
------------------------------------------------------------------------
POWER MIG 255
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D-6
D-6
MAINTENANCE
ACCESSORIES AND EXPENDABLE REPLACEMENT PARTS FOR
MAGNUM 250L GUN AND CABLE ASSEMBLIES
TABLE D.2
DESCRIPTION
PART NO.
ENGLISH SIZE
METRIC SIZE
Cable Liner
For 15 ft (4.5 m) or Shorter Cable
KP1934-2
KP1934-1
KP1955-1
0.025-0.030 in.
0.035-0.045 in.
3/64 in. (Alum. Wire)
0.6 - 0.8 mm
0.9 - 1.2 mm
1.2 mm (Alum. Wire)
Contact Tips
KP2020-6B1
KP2020-7B1
KP2020-1B1*
KP2020-2B1*
0.025 in.
0.030 in.
0.035 in.
0.045 in.
0.6 mm
0.8 mm
0.9 mm
1.2 mm
Standard Duty
Heavy Duty
KP2021-1B1
KP2021-2B1
0.035 in.
0.045 in.
0.9 mm
1.2 mm
KP2021-5B1
KP2021-6B1
KP2022-1B1
KP2022-2B1
0.025 in.
0.030 in.
0.035 in.
0.045 in.
0.6 mm
0.8 mm
0.9 mm
1.2 mm
Tapered
Tab (For Aluminum)
KP2010-5B1
3/64 in. (Alum. wire)
1.2 mm (Alum. Wire)
Gas Nozzles
Fixed (Flush)
KP1931-1
KP1931-2*
KP1931-3
3/8 in.
1/2 in.
5/8 in.
9.5 mm
12.1 mm
15.9 mm
(Recessed)
KP1930-1
KP1930-2
KP1930-3
3/8 in.
5/8 in.
5/8 in.
9.5 mm
15.9 mm
15.9 mm
(Requires: Gas Diffuser Assembly)
Adjustable Slip-On
KP2026-3*
0.025-0.045 in.
0.6-1.2 mm
KP1935-2
KP1935-1
1/2 in.
5/8 in.
12.7 mm
15.9 mm
(Requires: Nozzle Insulator Assembly)
(Requires: Gas Diffuser Assembly)
KP2025-1
KP2026-2
KP2026-1
0.25-0.030 in.
0.35-0.045 in.
0.6-0.8 mm
0.9-1.2 mm
Gasless Nozzle (for Innershield®)
KP1947-1**
Gun Tube Assembly
Standard (60 Degrees)
45 Degrees
KP2015-1*
KP2041-1
*Included with Power MIG 255.
**Requires S19418-1 Gas Diffuser Assembly.
POWER MIG 255
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Section E-1
Section E-1
TABLE OF CONTENTS
- THEORY OF OPERATION SECTION -
Theory of Operation...............................................................................................Section E
Input Line Voltage and Main Transformer.....................................................................E-2
Output Rectification and Feedback Control.................................................................E-3
Constant Voltage Output ..............................................................................................E-4
Wire Drive Motor and Feedback...................................................................................E-5
Thermal and Overload Protection.................................................................................E-6
Overcurrent Protection...........................................................................................E-6
Wire Feed Overload Protection..............................................................................E-6
SCR Operation..............................................................................................................E-7
FIGURE E.1 – BLOCK LOGIC DIAGRAM
FAN
GAS
MOTOR
SOLENOID
WIRE
DRIVE
MOTOR
WIRE
SPEED
CONTROL
BOARD
ARC
VOLTAGE
TACH
115 VAC
GUN TRIGGER
FEEDBACK
RECTIFIER
DIODE
BRIDGE
G
A
T
30 VAC
E
SNUBBER
BOARD
S
I
LINE
SWITCH
G
N
A
L
POWER
ENHANCEMENT
CHOKE
C
A
P
A
C
I
T
O
R
S
OUTPUT
CHOKE
POSITIVE
TERMINAL
F
RECONNECT
E
E
D
B
A
C
K
MAIN
TRANSFORMER
SCR
RECTIFIER
NEGATIVE
TERMINAL
SHUNT
POWER MIG 255
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E-2
E-2
THEORY OF OPERATION
FIGURE E.2 — INPUT LINE VOLTAGE AND MAIN TRANSFORMER.
FAN
GAS
MOTOR
SOLENOID
WIRE
DRIVE
MOTOR
WIRE
SPEED
CONTROL
BOARD
ARC
VOLTAGE
TACH
115 VAC
GUN TRIGGER
FEEDBACK
RECTIFIER
DIODE
BRIDGE
G
A
T
30 VAC
E
SNUBBER
BOARD
S
I
LINE
SWITCH
G
N
A
L
POWER
ENHANCEMENT
CHOKE
C
A
P
A
C
I
T
O
R
S
OUTPUT
CHOKE
POSITIVE
TERMINAL
F
RECONNECT
E
E
D
B
A
C
K
MAIN
TRANSFORMER
SCR
RECTIFIER
NEGATIVE
TERMINAL
SHUNT
gate drive circuitry. The weld power windings connect
to the main SCR Rectifier and via the Snubber Board
to the Rectifier Diode Bridge. This AC voltage is recti-
fied and then regulated by the control board. The
resultant +15 VDC and +5 VDC voltages supply power
to the control board circuitry. The 115 VAC winding (X8
and X9) supplies power, through the control board, to
the thermostatically controlled fan motor.
INPUT LINE VOLTAGE
AND MAIN TRANSFORMER
The desired single phase input power is connected to
the POWER MIG 255 through a line switch located on
the front panel.
A reconnect panel allows the user to configure the
machine for the desired input voltage. This AC input
voltage is applied to the primary of the main trans-
former. The main transformer converts the high
voltage, low current input power to a low voltage, high
current output. In addition, the main transformer also
has an isolated center tapped 30 VAC auxiliary winding
that supplies power to the Control Board for the SCR
The fan is designed to come on automatically when
weld arc is established. The fan will stay on for a mini-
mum of six minutes after the weld arc is terminated.
The fan will also stay on when the machine’s welding
and feeding are disabled during thermostatic over-tem-
perature protection. (See Thermal and Overload
Protection.)
NOTE: Unshaded areas of Block Logic
Diagram are the subject of discussion
POWER MIG 255
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E-3
E-3
THEORY OF OPERATION
FIGURE E.3 — OUTPUT RECTIFICATION AND FEEDBACK.
FAN
GAS
MOTOR
SOLENOID
WIRE
DRIVE
MOTOR
WIRE
SPEED
CONTROL
BOARD
ARC
VOLTAGE
TACH
115 VAC
GUN TRIGGER
FEEDBACK
RECTIFIER
DIODE
BRIDGE
G
A
T
30 VAC
E
SNUBBER
BOARD
S
I
LINE
SWITCH
G
N
A
L
POWER
ENHANCEMENT
CHOKE
C
A
P
A
C
I
T
O
R
S
OUTPUT
CHOKE
POSITIVE
TERMINAL
F
RECONNECT
E
E
D
B
A
C
K
MAIN
TRANSFORMER
SCR
RECTIFIER
NEGATIVE
TERMINAL
SHUNT
the commands of the ARC Voltage Control poten-
tiometer with the feedback signals. The appropriate
gate firing pulses are generated by the control board
and applied to the SCR rectifier assembly. The control
board controls the firing of the SCRs, thus controlling
the output of the machine. See SCR Operation. The
control board also powers and commands the gas
solenoid, fan motor, and the wire drive motor.
OUTPUT RECTIFICATION AND
FEEDBACK CONTROL
The AC output from the main transformer secondary
weld winding is rectified and controlled through the
SCR rectifier assembly. Output voltage and current are
sensed at the shunt and output terminals and are fed
back to the control board. The control board compares
NOTE: Unshaded areas of Block Logic
Diagram are the subject of discussion
POWER MIG 255
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E-4
E-4
THEORY OF OPERATION
FIGURE E.4 — CONSTANT VOLTAGE OUTPUT.
FAN
GAS
MOTOR
SOLENOID
WIRE
DRIVE
MOTOR
WIRE
SPEED
CONTROL
BOARD
ARC
VOLTAGE
TACH
115 VAC
GUN TRIGGER
FEEDBACK
RECTIFIER
DIODE
BRIDGE
G
A
T
30 VAC
E
SNUBBER
BOARD
S
I
LINE
SWITCH
G
N
A
L
POWER
ENHANCEMENT
CHOKE
C
A
P
A
C
I
T
O
R
S
OUTPUT
CHOKE
POSITIVE
TERMINAL
F
RECONNECT
E
E
D
B
A
C
K
MAIN
TRANSFORMER
SCR
RECTIFIER
NEGATIVE
TERMINAL
SHUNT
power factor enhancement choke is filtered by the
capacitor bank resulting in a constant voltage DC out-
put. Since the output choke is in series with the posi-
tive leg of the rectifier and also in series with the gun
and welding load, a filtered constant voltage output is
applied to the output terminals of the machine.
CONSTANT VOLTAGE OUTPUT
The controlled DC output from the SCR rectifier
assembly is supplied to the power factor enhancement
choke which limits the rate at which the supply current
rises through the capacitors. The DC output from the
NOTE: Unshaded areas of Block Logic
Diagram are the subject of discussion
POWER MIG 255
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E-5
E-5
THEORY OF OPERATION
FIGURE E.5 — WIRE DRIVE MOTOR AND FEEDBACK.
FAN
GAS
MOTOR
SOLENOID
WIRE
DRIVE
MOTOR
WIRE
SPEED
CONTROL
BOARD
ARC
VOLTAGE
TACH
115 VAC
GUN TRIGGER
FEEDBACK
RECTIFIER
DIODE
BRIDGE
G
A
T
30 VAC
E
SNUBBER
BOARD
S
I
LINE
SWITCH
G
N
A
L
POWER
ENHANCEMENT
CHOKE
C
A
P
A
C
I
T
O
R
S
OUTPUT
CHOKE
POSITIVE
TERMINAL
F
RECONNECT
E
E
D
B
A
C
K
MAIN
TRANSFORMER
SCR
RECTIFIER
NEGATIVE
TERMINAL
SHUNT
board compares this feedback signal with the com-
mands set forth by the Wire Speed Control poten-
tiometer and sends the appropriate armature voltage to
the wire drive motor. The drive motor speed is thus
controlled which in turn regulates the electrode wire
feed speed through the gun.
WIRE DRIVE MOTOR
AND FEEDBACK
The wire drive motor is controlled by the control board.
A motor speed feedback signal is generated at the
motor tach and sent to the control board. The control
NOTE: Unshaded areas of Block Logic
Diagram are the subject of discussion
POWER MIG 255
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E-6
E-6
THEORY OF OPERATION
OVERCURRENT PROTECTION
THERMAL AND OVERLOAD
PROTECTION
The machine will automatically reduce the output if the
load on the machine exceeds 300 to 320 amperes.
This protects the welding power SCR’s from excessive
short circuit currents and from exceeding their temper-
ature rating before the thermostats can react.
The POWER MIG 255 has built-in protective ther-
mostats that respond to excessive temperatures. One
is located on the output choke. The other thermostat is
located on the SCR heat sink assembly. They open the
wire feed and welder output circuits if the machine
exceeds the maximum safe operating temperature.
This can be caused by a frequent overload, or high
ambient temperature.
WIRE FEED OVERLOAD PROTECTION
The POWER MIG has solid state overload protection
of the wire drive motor. If the motor becomes over-
loaded, the protection circuitry turns off the wire feed
speed and gas solenoid. Check for proper size tip liner,
and drive rolls, for any obstructions or bends in the gun
cable, and any other factors that would impede the wire
feeding. To resume welding, simply pull the trigger.
There is no circuit breaker to reset, as the protection is
done with reliable solid state electronics.
The thermostats are self-resetting once the machine
cools sufficiently. If the thermostat shutdown is caused
by excessive output or duty cycle and the fan is oper-
ating normally, the power switch may be left on and the
reset should occur within a 15 minute period. If the fan
is not turning or the air intake louvers are obstructed,
then the input power must be removed and the fan
problem or air obstruction be corrected.
POWER MIG 255
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E-7
E-7
THEORY OF OPERATION
FIGURE E.6 — SCR OPERATION.
INPUT
CATHODE
OUTPUT
GATE
NOTE: AS THE GATE
PULSE IS APPLIED
LATER IN THE CYCLE
THE SCR OUTPUT
IS DECREASED.
ANODE
the off state and the remainder of the time in the on
state. The amount of time spent in the ON state is con-
trolled by the gate.
SCR OPERATION
A silicon controlled rectifier (SCR) is a three terminal
device used to control rather large currents to a load.
An SCR acts very much like a switch. See Figure E.6
for a graphical representation of SCR operation. When
a gate signal is applied to the SCR it is turned ON and
there is current flow from anode to cathode. In the ON
state the SCR acts like a closed switch. When the SCR
is turned OFF there is no current flow from anode to
cathode thus the device acts like an open switch. As
the name suggests, the SCR is a rectifier, so it passes
current only during positive half cycles of the AC sup-
ply. The positive half cycle is the portion of the sine
wave in which the anode of the SCR is more positive
than the cathode.
An SCR is fired by a short burst of current into the gate.
This gate pulse must be more positive than the cath-
ode voltage. Since there is a standard PN junction
between gate and cathode, the voltage between these
terminals must be slightly greater than 0.6V. Once the
SCR has fired it is not necessary to continue the flow
of gate current. As long as current continues to flow
from anode to cathode the SCR will remain on. When
the anode to cathode current drops below a minimum
value, called holding current, the SCR will shut off. This
normally occurs as the AC supply voltage passes
through zero into the negative portion of the sine wave.
If the SCR is turned on early in the positive half cycle,
the conduction time is longer resulting in greater SCR
output. If the gate firing occurs later in the cycle the
conduction time is less resulting in lower SCR output.
When an AC supply voltage is applied to the SCR, the
device spends a certain portion of the AC cycle time in
POWER MIG 255
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E-8
E-8
NOTES
POWER MIG 255
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Section F-1
Section F-1
TABLE OF CONTENTS
- TROUBLESHOOTING & REPAIR SECTION -
Troubleshooting & Repair Section ........................................................................Section F
How to Use Troubleshooting Guide..............................................................................F-2
PC Board Troubleshooting Procedures and Replacement...........................................F-3
Troubleshooting Guide..................................................................................................F-4
Test Procedures
Main Transformer Test ..........................................................................................F-11
Rectifier Diode Bridge Test...................................................................................F-15
Static SCR Rectifier Assembly Test .....................................................................F-19
Active SCR Rectifier Assembly Test.....................................................................F-23
Wire Drive Motor and Tachometer Feedback Test...............................................F-27
Oscilloscope Waveforms
Normal Open Circuit Voltage Waveform ..............................................................F-31
Typical Output Voltage Waveform - Machine Loaded..........................................F-32
Abnormal Output Voltage Waveform - Machine Loaded One Output SCR Not Functioning .............F-33
Abnormal Open Circuit Voltage Output Capacitor Bank Not Functioning...........F-34
Typical SCR Gate Voltage Waveform ...................................................................F-35
Replacement Procedures
Control PC Board Removal and Replacement.....................................................F-37
Wire Drive Assembly Removal and Replacement................................................F-41
SCR Output Rectifier Removal and Replacement ...............................................F-45
Capacitor Bank Removal and Replacement ........................................................F-49
Main Transformer and Output Choke Removal and Replacement......................F-51
Fan Motor and Fan Removal and Replacement ..................................................F-55
Retest After Repair......................................................................................................F-57
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F-2
F-2
TROUBLESHOOTING & REPAIR
HOW TO USE TROUBLESHOOTING GUIDE
CAUTION
Service and repair should be performed by only Lincoln Electric Factory Trained Personnel.
Unauthorized repairs performed on this equipment may result in danger to the technician and machine
operator and will invalidate your factory warranty. For your safety and to avoid Electrical Shock, please
observe all safety notes and precautions detailed throughout this manual.
This Troubleshooting Guide is provided to help
you locate and repair possible machine
malfunctions. Simply follow the three-step
procedure listed below.
Step 3. PERFORM COMPONENT TESTS. The
last column, labeled “Recommended Course of
Action” lists the most likely components that may
have failed in your machine. It also specifies the
appropriate test procedure to verify that the
subject component is either good or bad. If there
are a number of possible components, check the
components in the order listed to eliminate one
possibility at a time until you locate the cause of
your problem.
Step 1. LOCATE PROBLEM (SYMPTOM). Look
under the column labeled “PROBLEM
(SYMPTOMS)”. This column describes possible
symptoms that the machine may exhibit. Find
the listing that best describes the symptom that
the machine is exhibiting. Symptoms are
grouped into three main categories: Feeding
Problems and Welding Problems.
All of the referenced test procedures referred to in
the Troubleshooting Guide are described in detail
at the end of this chapter. Refer to the
Troubleshooting and Repair Table of Contents to
locate each specific Test Procedure. All of the
referred to test points, components, terminal
strips, etc., can be found on the referenced
electrical wiring diagrams and schematics. Refer
to the Electrical Diagrams Section Table of
Contents to locate the appropriate diagram.
Step 2. PERFORM EXTERNAL TESTS. The
second column, labeled “POSSIBLE AREAS OF
MISADJUSTMENT(S)”, lists the obvious external
possibilities that may contribute to the machine
symptom. Perform these tests/checks in the
order listed. In general, these tests can be
conducted without removing the case
wrap-around cover.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-
tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call
1-888-935-3877.
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F-3
F-3
TROUBLESHOOTING & REPAIR
PC BOARD TROUBLESHOOTING PROCEDURES
- Remove the PC board from the static-shielding bag
and place it directly into the equipment. Don’t set the
PC board on or near paper, plastic or cloth which
could have a static charge. If the PC board can’t be
installed immediately, put it back in the static-shield-
ing bag.
WARNING
ELECTRIC SHOCK
can kill.
•
Have an electrician install and
service this equipment. Turn the
input power OFF at the fuse box
before working on equipment. Do
not touch electrically hot parts.
- If the PC board uses protective shorting jumpers,
don’t remove them until installation is complete.
- If you return a PC board to The Lincoln Electric
Company for credit, it must be in the static-shielding
bag. This will prevent further damage and allow prop-
er failure analysis.
CAUTION
Sometimes machine failures appear to be due to PC
board failures. These problems can sometimes be
traced to poor electrical connections. To avoid prob-
lems when troubleshooting and replacing PC boards,
please use the following procedure:
4. Test the machine to determine if the failure
symptom has been corrected by the
replacement PC board.
NOTE: It is desirable to have a spare (known good)
PC board available for PC board troubleshooting.
1. Determine to the best of your technical ability
that the PC board is the most likely component
causing the failure symptom.
NOTE: Allow the machine to heat up so that all
electrical components can reach their operating
temperature.
2. Check for loose connections at the PC board
to assure that the PC board is properly
connected.
5. Remove the replacement PC board and
substitute it with the original PC board to
recreate the original problem.
3. If the problem persists, replace the suspect PC
board using standard practices to avoid static
electrical damage and electrical shock. Read
the warning inside the static resistant bag and
perform the following procedures:
a. If the original problem does not reappear by
substituting the original board, then the PC
board was not the problem. Continue to look
for bad connections in the control wiring
harness, junction blocks, and terminal strips.
PC board can be damaged by static electricity.
b. If the original problem is recreated by the
substitution of the original board, then the PC
board was the problem. Reinstall the
replacement PC board and test the machine.
- Remove your body’s static
charge before opening the static-
shielding bag. Wear an anti-static
wrist strap. For safety, use a 1
Meg ohm resistive cord connected
6. Always indicate that this procedure was
followed when warranty reports are to be
submitted.
to
a
grounded part of the
ATTENTION
Static-Sensitive
Devices
Handle only at
Static-Safe
equipment frame.
NOTE: Following this procedure and writing on the
warranty report, “INSTALLED AND SWITCHED PC
BOARDS TO VERIFY PROBLEM,” will help avoid
denial of legitimate PC board warranty claims.
- If you don’t have a wrist strap,
touch an un-painted, grounded,
part of the equipment frame. Keep
touching the frame to prevent
static build-up. Be sure not to
touch any electrically live parts at
the same time.
Workstations
- Tools which come in contact with the PC board must
be either conductive, anti-static or static-dissipative.
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F-4
F-4
TROUBLESHOOTING & REPAIR
TROUBLESHOOTING GUIDE
Observe Safety Guidelines
detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
OUTPUT PROBLEMS
Major Physical or Electrical Damage 1. Contact your local Lincoln 1. Contact The Lincoln Electric
is Evident
Electric Authorized Field Service
Facility.
Service Dept. 1-888-935-3877
1. Check input power switch (S1).
It may be faulty.
Machine is dead — no open circuit 1. Make certain that the input
voltage output and no wire feed
when gun trigger is pulled. The
machine display may be lit.
power switch is in the "ON" posi-
tion.
2. Check for lose or broken wires
at the reconnect panel.
2. Check the input voltage at the
machine. Input voltage must 3. Perform Main Transformer
match the rating plate and the
reconnect panel.
Test.
4. Perform Rectifier Diode Bridge
3. Blown or missing fuses in the
input line.
Test.
5. Check the thermostats and
associated leads for loose or
broken connections. See wiring
diagram.
4. The thermostats may be open
due to machine overheating. If
machine operates normally after
a cooling off period then check
for proper fan operation and 6. The control board may be faulty.
ventilation. Make certain that the
machine's duty cycle is not
being exceeded.
Replace.
5. Check the trigger circuit. Leads
#324 to #325 should have conti-
nuity (zero ohms) when the gun
trigger is pulled. If not then the
gun may be faulty — replace.
6. Make sure unit is not connected
to a portable generator.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-
tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call
1-888-935-3877.
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F-5
F-5
TROUBLESHOOTING & REPAIR
TROUBLESHOOTING GUIDE
Observe Safety Guidelines
detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
OUTPUT PROBLEMS (Continued)
No open circuit voltage output but 1. Check the input voltage at the 1. Check for loose or broken con-
wire feeds normally when gun trig-
ger is pulled.
machine. Input voltage must
match the rating plate and the
reconnect panel.
nections at the output terminals,
the chokes, the capacitor bank
and all heavy current carrying
leads. See Wiring Diagram.
2. The gun may be faulty. Check
or replace.
2. Make sure that the transformer
secondary leads are securely
connected to the SCR rectifier
assembly.
3. Perform the SCR Rectifier
Assembly Tests.
4. Perform Main Transformer
Test.
5. The control board may be faulty.
Replace.
Wire feeds but welding output is low 1. Make sure that the proper wire 1. Check for loose or faulty con-
causing wire to “stub”. Welds are
“cold”. Machine cannot obtain full
and procedures are being used.
nections of the heavy current
carrying leads.
rated output of 200 amps at 28 volts. 2. Check gun and work cable for
loose or faulty connections.
2. The output capacitor bank may
be faulty. Check for loose con-
nections at the capacitors. Also
check for leaky capacitors.
Replace if necessary.
WARNING: The liquid elec-
trolyte in these capacitors is
toxic. Avoid contact with any
portion of your body.
3. Perform the SCR Rectifier
Assembly Tests.
4. Perform the Main Transformer
Test.
5. The control board may be faulty.
Replace.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-
tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call
1-888-935-3877.
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F-6
F-6
TROUBLESHOOTING & REPAIR
TROUBLESHOOTING GUIDE
Observe Safety Guidelines
detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
OUTPUT PROBLEMS (Continued)
The output voltage and wire feed is 1. Remove the gun. If the problem 1. Check the machine's internal
present continuously or pulsing
when gun trigger is NOT activated.
is resolved the gun trigger circuit
is faulty. Repair or replace.
trigger leads for grounds or
shorts. See Wiring Diagram.
2. If problem persists when gun 2. The control board may be faulty.
assembly is removed from
machine, then the problem is
within the POWER MIG 255.
Replace.
The output voltage is present contin- Contact your local Lincoln Electric
uously when gun trigger is NOT acti- Authorized Field Service Facility.
vated.
1. Perform the SCR Rectifier
Assembly Tests.
2. The control board may be faulty.
Replace.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-
tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call
1-888-935-3877.
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F-7
F-7
TROUBLESHOOTING & REPAIR
TROUBLESHOOTING GUIDE
Observe Safety Guidelines
detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
FUNCTION PROBLEMS
No control of arc voltage. Wire feed- 1. The arc voltage control poten- 1. The arc voltage control poten-
ing is normal.
tiometer may be dirty. Rotate
several times and check if prob-
lem is resolved.
tiometer may be faulty. Check or
replace. See Wiring Diagram.
2. Perform the SCR Rectifier
Assembly Tests.
3. The control board may be faulty.
Replace.
There is no gas flow when gun trig- 1. Check gas source and hoses for 1. Check the gas solenoid by dis-
ger is pulled. Wire feeds and weld
voltage is present.
leaks or kinks.
connecting it from the control
board (Plug J8) and applying a
12 VDC external supply to the
gas solenoid. If the solenoid
does NOT activate then it may
be faulty. Replace.
2. The control broad may be faulty.
Replace.
The machine stops feeding wire 1. Check for adequate wire supply. 1. Check the motor armature cur-
while welding.
rent. Normal armature current is
2.0 to 2.7 amps maximum. If
the motor armature current is
normal the control board may be
faulty. Replace.
2. Check for mechanical restric-
tions in the wire feeding path.
The gun may be clogged.
3. Check gun liner and tip are cor-
rect for wire size being used.
2. If the motor armature current is
high (over 2.7 amps) and there
are NO restrictions in the wire
feeding path then the motor or
gear box may be defective.
Replace.
4. Check spindle for ease of rota-
tion.
5. If Timer Option Kit is installed,
make sure spot timer knob is set
to OFF.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-
tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call
1-888-935-3877.
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F-8
F-8
TROUBLESHOOTING & REPAIR
TROUBLESHOOTING GUIDE
Observe Safety Guidelines
detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
WIRE FEEDING PROBLEMS
No control of wire feed speed. Other 1. The wire feed speed control 1. The Wire Speed Control poten-
machine functions are normal
may be dirty. Rotate several
times and check if problem is
resolved.
tiometer may be faulty. Check or
replace. See Wiring Diagram.
2. Perform the Wire Drive Motor
and Tachometer Feedback
Test.
3. The control board may be faulty.
Replace.
There is no wire feed when gun trig- 1. Check for adequate wire supply. 1. Perform the Wire Drive Motor
ger is pulled. Normal open circuit
voltage is present.
and Tachometer Feedback
Test.
2. If the drive rolls are turning then
check for a mechanical restric-
tion in the wire feed path.
2. The Wire Feed Control poten-
tiometer may be faulty. Check or
replace. See Wiring Diagram.
3. The gun liner may be clogged.
Check or replace.
3. The control board may be faulty.
Replace.
4. If the drive rolls are NOT turning
when the gun trigger is pulled
then contact your local Lincoln
Electric Authorized Field Service
Facility.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-
tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call
1-888-935-3877.
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F-9
F-9
TROUBLESHOOTING & REPAIR
TROUBLESHOOTING GUIDE
Observe Safety Guidelines
detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
WELDING PROBLEMS
The arc is unstable and or “hunting”. 1. Check for worn or melted con- 1. Check for loose connections at
tact tip.
the output terminals, the
chokes, the capacitor bank and
all heavy current carrying leads.
See Wiring Diagram.
2. Check for loose or faulty con-
nections on the work and elec-
trode cables.
2. Make sure that the transformer
secondary leads are securely
connected to the SCR rectifier
assembly.
3. Make sure electrode polarity or
welding process being used, is
correct.
4. Check for rusty or dirty wire.
3. The output capacitor bank may
be faulty. Check for loose con-
nections at the capacitors. Also
check for leaky capacitors.
Replace if necessary.
5. Make sure machine settings and
gas are correct for process
being used.
WARNING: The liquid elec-
trolyte in these capacitors is
toxic. Avoid contact with any
portion of your body.
4. Perform the SCR Rectifier
Assembly Tests.
5. The control board may be faulty.
Replace.
Weld bead is narrow or ropy. May 1. Make sure the weld procedure 1. The output capacitor bank may
have porosity with electrode stub-
bing into plate.
and electrode polarity is correct
for the process being used.
be faulty. Check for loose con-
nections at the capacitors. Also
check for leaky capacitors.
Replace if necessary.
2. Make sure shielding gas is cor-
rect and flow is proper.
WARNING: The liquid elec-
trolyte in these capacitors is
toxic. Avoid contact with any
portion of your body.
3. Make sure the weld joint is not
“contaminated”.
2. The control board may be faulty.
Replace.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-
tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call
1-888-935-3877.
POWER MIG 255
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F-10
F-10
TROUBLESHOOTING & REPAIR
TROUBLESHOOTING GUIDE
Observe Safety Guidelines
detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
WELDING PROBLEMS (Continued)
The contact tip seizes in the gas
diffuser.
1. The tip being over heated due to 1. Make sure tip is tight in diffuser.
excessive current and/or high
duty cycle welding.
2. A light application of high tem-
perature anti-sieze lubricant
(such as Lincoln E2607
Graphite Grease) may be
applied to the contact tip
threads.
The welding arc is variable and
sluggish.
1. Check the welding cable con- 1. Perform the SCR Rectifier
nections for loose or faulty con-
nections.
Assembly Tests.
2. The control board may be faulty.
Replace.
2. Make sure the wire feed speed,
voltage, and shielding gas are
correct for the process being
used.
The arc striking is poor.
1. Check the welding cable con- 1. The output capacitor bank may
nections for loose or faulty con-
nections.
be faulty. Check for loose con-
nections at the capacitors. Also
check for leaky capacitors.
Replace if necessary.
2. Make sure the wire feed speed,
voltage, and shielding gas are
correct for the process being
used.
WARNING: The liquid elec-
trolyte in these capacitors is
toxic. Avoid contact with any
portion of your body.
2. The control board may be faulty.
Replace.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-
tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call
1-888-935-3877.
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F-11
F-11
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER TEST
WARNING
Service and repair should be performed by only Lincoln Electric factory trained
personnel. Unauthorized repairs performed on this equipment may result in danger
to the technician or machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and pre-
cautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to per-
form the test / repairs safely, contact the Lincoln Electric Service Department for
electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
This procedure will determine if the correct voltages are being:
a. Applied to the primary windings of the main transformer.
b. Induced on the secondary and auxiliary windings of the main transformer.
MATERIALS NEEDED
Volt/Ohm Meter
3/8 in. Nutdriver
5/16 in. Nutdriver
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F-12
F-12
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER TEST (continued)
FIGURE F.1 — G3521 CONTROL PC BOARD AND M19248 SNUBBER PC BOARD
MAIN TRANSFORMER TEST POINTS.
X5
(6J6)
X6
J6
J5
(5J6)
X7
(4J6)
X9
(8J5)
X8
(16J5)
#206
(3J5)
#209S
(6J9)
J3
J8
J1
J9
#208S
(2J9)
J4
J2
4. Locate plug J5 and plug J6 on the
G3521 control PC board, and J9 on the
M19248 snubber PC board. See Figure
F.1.
TEST PROCEDURE
WARNING
The ON/OFF POWER SWITCH will be
“hot” during these tests.
----------------------------------------------------------
NOTE: The location of plugs may vary
depending on the machine code.
5. Locate the following leads on plug J6
on the G3521 control PC board:
NOTE: Secondary voltages will vary pro-
portionately with the primary input voltage.
PLUG
LOCATION
1. Disconnect the main input power sup-
ply to the machine.
LEAD
X5
X6
X7
6J6
5J6
4J6
2. Remove the case top and side panels
with a 3/8 in. nutdriver.
3. Remove the tool tray with a 5/16 in. nut-
driver.
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F-13
F-13
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER TEST (continued)
6. Connect main input power to the
machine.
11. Turn the machine ON.
12. Make the following voltage tests at plug
J5.
7. Turn the POWER MIG 255 ON/OFF
POWER SWITCH to ON.
a. Turn the machine OFF between
each test.
8. Carefully make the following voltage
tests at plug J6.
b. Carefully insert the meter probes
into the back of each Molex plug
pin cavity to perform the test.
a. Turn the machine OFF between
each test.
TO
LEAD
EXPECTED
VOLTAGE
FROM
LEAD
b. Carefully insert the meter probes
into the back of each Molex plug
pin cavity to perform the test.
X9
115VAC
X8
(8J5)
(16J5)
FROM
LEAD
TO
LEAD
EXPECTED
VOLTAGE
c. If the voltage tested is incorrect,
check for loose or broken leads
between the test points and the
main transformer.
X5
(6J6)
X6
(5J6)
15VAC
30VAC
15VAC
X5
(6J6)
X7
(4J6)
d. If the voltage is not corrected, go to
step 16.
X6
X7
(5J6)
(4J6)
13. Turn OFF the machine power.
9. Turn OFF the machine.
10. Locate the following leads on plug J5
on the G3521 control PC board. See
Figure F.1.
PLUG
LEAD
LOCATION
X8
X9
16J5
8J5
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F-14
F-14
TROUBLESHOOTING AND REPAIR
MAIN TRANSFORMER TEST (continued)
14. Locate the following leads on plug J9
on the M19248 snubber PC board and
on plug J5 on the G3521 control PC
board. See Figure F.1.
c. If any of the voltages tested are
incorrect, check for loose or broken
leads between the test points and
the main transformer.
G3521:
d. If ALL the voltages tested are incor-
rect or missing, go to step 16.
PLUG
LOCATION
LEAD
17. Test for correct nameplate input
voltage between the H1 lead at the
ON/OFF POWER SWITCH to H2 or
H3 (H5 if connected for 575 VAC) at
the reconnect panel. Voltage tested will
vary depending on input voltage
connection. See wiring diagram for test
point locations.
206
3J5
M19248:
PLUG
LOCATION
LEAD
208S
209S
2J9
6J9
a. If the voltage test is incorrect,
15. Turn the machine ON.
-check for loose or broken leads
between the reconnect panel and
the ON/OFF POWER SWITCH.
16. Make the following voltage tests at plug
J9 on the M19248 snubber PC board
and at plug J5 on the G3521 control PC
board.
-test the ON/OFF POWER
SWITCH for proper operation.
a. Turn the machine OFF between
each test.
b. If the correct nameplate voltage is
being applied to the main trans-
former and one or more of the sec-
ondary voltages are missing or are
incorrect, the main transformer may
be faulty. Replace.
b. Carefully insert the meter probes
into the back of each Molex plug
pin cavity to perform the test.
TO
LEAD
EXPECTED
VOLTAGE
FROM
LEAD
209S
(6J9 on
M19248)
56VAC
28VAC
28VAC
208S
(2J9 on
M19248)
206
(3J5 on
G3521)
208S
(2J9 on
M19248)
206
209S
(3J5 on
G3521)
(6J9 on
M19248)
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F-15
F-15
TROUBLESHOOTING & REPAIR
RECTIFIER DIODE BRIDGE TEST
WARNING
Service and repair should only be performed by Lincoln Electric factory trained
personnel. Unauthorized repairs performed on this equipment may result in dan-
ger to the technician or machine operator and will invalidate your factory war-
ranty. For your safety and to avoid electrical shock, please observe all safety
notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to per-
form the test/repairs safely, contact the Lincoln Electric service department for
technical troubleshooting assistance before you proceed. Call 1-888-935-3877.
-------------------------------------------------------------------------------------------------------------------
TEST DESCRIPTION
This test will determine if the correct voltages are being:
a. Applied to the diode bridge.
b. Supplied from diode bridge to the control PC board.
MATERIALS NEEDED
3/8 in. Nutdriver
Volt-ohmmeter
POWER MIG 255 wiring diagrams (See Electrical Diagrams Section of this Manual)
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F-16
F-16
TROUBLESHOOTING & REPAIR
RECTIFIER DIODE BRIDGE TESTING (continued)
FIGURE F.2 — G3521 RECTIFIER DIODE BRIDGE LOCATION.
RECTIFIER
DIODE BRIDGE
(D2)
TEST PROCEDURE
LEAD
1. Disconnect the main AC input power to
the machine.
208R
209R
354
2. Remove the case top and side panels
with a 3/8 in. nutdriver.
206
Leads #208R, #209R, and #354 are
connected to the rectifier diode bridge
(D2). See Figure F.2. Lead #206 is
connected at the output shunt. See the
wiring diagram.
3. Perform the Main Transformer Test to
ensure the proper voltages are supplied
to the M19248 snubber PC board.
4. Locate the following leads:
5. Connect main input power to the
machine.
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F-17
F-17
TROUBLESHOOTING & REPAIR
RECTIFIER DIODE BRIDGE TESTING (continued)
6. Turn the POWER MIG 255 ON/OFF
POWER SWITCH to ON.
9. Make the following voltage test:
a. Turn the machine OFF between
each test.
7. Carefully make the following voltage
tests:
b. Carefully connect the meter probes
to the exposed lead connections.
a. Turn the machine OFF between
each test.
c. Turn the machine ON to conduct
the voltage test.
b. Carefully connect the meter plugs
to the exposed lead connections.
TO
LEAD
EXPECTED
VOLTAGE
FROM
LEAD
c. Turn the machine ON to conduct
the voltage test.
206
36 VDC
354
TO
LEAD
EXPECTED
VOLTAGE
FROM
LEAD
10. If the DC voltage tested is incorrect or
missing, and the AC voltages are cor-
rect, the rectifier diode bridge may be
faulty.
206
206
28 VAC
28 VAC
208R
209R
8. If any of the AC voltages tested are
incorrect or missing, check the M19248
snubber PC board and associated
leads and connections. See the wiring
diagram.
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F-18
F-18
NOTES
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F-19
F-19
TROUBLESHOOTING & REPAIR
STATIC SCR RECTIFIER ASSEMBLY TEST
WARNING
Service and repair should only be performed by Lincoln Electric factory trained
personnel. Unauthorized repairs performed on this equipment may result in dan-
ger to the technician or machine operator and will invalidate your factory war-
ranty. For your safety and to avoid electrical shock, please observe all safety
notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to per-
form the test/repairs safely, contact the Lincoln Electric service department for
technical troubleshooting assistance before you proceed. Call 1-888-935-3877.
-------------------------------------------------------------------------------------------------------------------
TEST DESCRIPTION
This test is used to quickly determine if an SCR or diode is shorted or “leaky.” See the
Machine Waveform Section in this manual for normal and abnormal output waveforms.
MATERIALS NEEDED
Analog Volt-ohmmeter
POWER MIG 255 wiring diagrams (See Electrical Diagrams Section of this Manual)
3/8 in. Nutdriver
5/16 in. Nutdriver
1/2 in. Open end or socket wrench
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F-20
F-20
TROUBLESHOOTING & REPAIR
STATIC SCR RECTIFIER ASSEMBLY TEST (continued)
FIGURE F.3 — REMOVE PLUGS J6 AND J9 TO PERFORM STATIC RECTIFIER ASSEMBLY TEST.
J6
J5
J3
J8
J1
J9
J4
J2
4. Verify that the capacitors have
completely discharged with a volt-
ohmmeter.
TEST PROCEDURE
1. Disconnect main AC input power to the
machine.
5. Disconnect plugs J6 from the G3521
control board and J9 from the M19248
snubber PC board. This electrically
isolates the SCR bridge assembly.
See Figure F.3.
2. Remove the case top and side panels
with a 3/8 in. nutdriver.
3. Remove the tool tray with a 5/16 in. nut-
driver.
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F-21
F-21
TROUBLESHOOTING & REPAIR
STATIC SCR RECTIFIER ASSEMBLY TEST (continued)
FIGURE F.4 — LOCATION OF
LEADS X2 AND X3.
FIGURE F.5 — SCR 1 TEST POINTS.
NEGATIVE
CAPACITOR
BANK BUSS
BAR
LEADS X2 AND X3
CONNECTION
9. Test for high or infinite resistance from
the cathode to the anode of SCR 1 by
reversing the meter leads. See Figure
F.5.
6. Disconnect leads X2 and X3 (braided
copper strap) from the negative capaci-
tor bank buss bar using a 1/2 in. open
end wrench. See Figure F.4.
a. If a high or infinite resistance is indi-
cated for both tests 6 and 7, the
SCR 1 is not “shorted”.
b. If a low resistance is indicated in
either tests 6 or 7, the SCR is faulty.
Replace the SCR assembly.
7. Separate leads X2 and X3 from the
negative capacitor bank buss bar. Be
sure there is no electrical contact.
10. Repeat steps 6 and 7 to test SCR 2.
NOTE: DO NOT DISASSEMBLE THE SCR
RECTIFIER HEAT SINK ASSEMBLY.
11. Reconnect leads X2 and X3 (braided
copper strap).
8. Test for high or infinite resistance from
the anode to the cathode of SCR 1
using an analog ohmmeter. See Figure
F.5.
12. Reconnect plugs J9 and J6.
13. If this test did not identify the problem,
or to further test the SCR, go to the
Active SCR Rectifier Assembly Test.
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F-22
F-22
NOTES
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F-23
F-23
TROUBLESHOOTING & REPAIR
ACTIVE SCR RECTIFIER ASSEMBLY TEST
WARNING
Service and repair should only be performed by Lincoln Electric factory trained
personnel. Unauthorized repairs performed on this equipment may result in dan-
ger to the technician or machine operator and will invalidate your factory war-
ranty. For your safety and to avoid electrical shock, please observe all safety
notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to per-
form the test/repairs safely, contact the Lincoln Electric service department for
technical troubleshooting assistance before you proceed. Call 1-888-935-3877.
-------------------------------------------------------------------------------------------------------------------
TEST DESCRIPTION
The Active SCR Rectifier Assembly Test will determine if the device is able to be gated
ON and conduct current from anode to cathode.
The Static SCR Rectifier Assembly Test must be performed before proceeding with the
Active SCR Test.
MATERIALS NEEDED
3/8 in. Nutdriver
5/16 in. Nutdriver
An SCR Tester as specified in this procedure
POWER MIG 255 wiring diagrams (See Electrical Diagrams Section of this Manual)
SCR Heat Sink Assembly Drawings
A volt-ohmmeter
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F-24
F-24
TROUBLESHOOTING & REPAIR
ACTIVE SCR RECTIFIER ASSEMBLY TEST (continued)
FIGURE F.6 — CONTROL BOARD MOLEX PLUG LOCATIONS FOR G3521 PC CONTROL BOARD.
J6
J5
J3
J8
J1
J9
J4
J2
4. Verify that the capacitors have
completely discharged with a volt-
ohmmeter.
TEST PROCEDURE
1. Disconnect main AC input power to the
machine.
5. Disconnect plugs J6 from the G3521
control board and J9 from the M19248
snubber PC board. This electrically
isolates the SCR bridge assembly.
See Figure F.6.
2. Remove the case top and side panels
with a 3/8 in. nutdriver.
3. Remove the tool tray with a 5/16 in. nut-
driver.
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F-25
F-25
TROUBLESHOOTING & REPAIR
ACTIVE SCR RECTIFIER ASSEMBLY TEST (continued)
6. Disconnect leads X2 and X3 (braided
copper strap) from the negative capaci-
tor bank buss bar using a 1/2 in. open
end wrench. See Figure F.7.
8. Use a commercial SCR tester or con-
struct the tester circuit shown in Figure
F.8. One 6-volt lantern battery can be
used. R1 and R2 resistor values are
±10%. Set voltmeter scale low, at
approximately 0-5 volts or 5-10 volts.
FIGURE F.7 — LOCATION OF
LEADS X2 AND X3.
a. Test the voltage level of the battery.
Short leads (A) and (C). Close
switch SW-1. Battery voltage
should be 4.5 volts or higher. If
lower, replace the battery.
NEGATIVE
CAPACITOR
BANK BUSS
BAR
FIGURE F.8 — SCR TESTER CIRCUIT
AND SCR CONNECTIONS.
LEADS X2 AND X3
CONNECTION
7. Separate leads X2 and X3 from the
negative capacitor bank buss bar. Be
sure there is no electrical contact.
NOTE: DO NOT DISASSEMBLE THE SCR
RECTIFIER HEAT SINK ASSEMBLY.
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F-26
F-26
TROUBLESHOOTING & REPAIR
ACTIVE SCR RECTIFIER ASSEMBLY TEST (continued)
9. Connect the tester to the SCR 1 as
shown in Figure F.8.
15. Reconnect the tester leads. See Figure
F.8.
a. Connect tester lead (A) to the
anode.
a. Connect tester lead (A) to the
cathode.
b. Connect tester lead (C) to the
cathode.
b. Connect tester lead (C) to the
anode.
c. Connect tester lead (G) to the gate.
10. Close switch SW-1.
c. Disconnect test lead (G) from the
gate.
16. Close switch SW-1.
NOTE: Switch SW-2 should be open.
11. Read meter for zero voltage.
17. Read meter for zero voltage.
a. If the voltage is zero, the SCR is
functioning.
a. If the voltage reading is higher than
zero, the SCR is shorted.
b. If the voltage is higher than zero,
the SCR is shorted.
12. Close or keep closed switch SW-1.
13. Close switch SW-2 for 2 seconds and
release and read meter.
18. Perform the Active Test Procedure out-
lined in Steps 6-15 for SCR 2.
a. If the voltage is 3 to 6 volts while
the switch is closed and after the
switch is open, the SCR is
functioning.
19. Replace all SCR assemblies that do not
pass the above tests.
20. Reconnect plug J6 onto the control PC
board and J9 to the snubber PC board.
b. If the voltage is 3 to 6 volts only
when the switch is closed or there
is no voltage when the switch is
closed, the SCR is defective.
21. Reconnect leads X2 and X3 to the neg-
ative capacitor bank bus bar.
22. Replace the tool tray and case sides.
NOTE: Be sure battery is functioning prop-
erly. A low battery can affect the results of
the test. Repeat Battery Test Procedure in
Step 6 if needed.
14. Open switch SW-1.
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F-27
F-27
TROUBLESHOOTING & REPAIR
WIRE DRIVE MOTOR AND TACHOMETER FEEDBACK TEST
WARNING
Service and repair should only be performed by Lincoln Electric factory trained
personnel. Unauthorized repairs performed on this equipment may result in dan-
ger to the technician or machine operator and will invalidate your factory war-
ranty. For your safety and to avoid electrical shock, please observe all safety
notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to per-
form the test/repairs safely, contact the Lincoln Electric service department for
technical troubleshooting assistance before you proceed. Call 1-888-935-3877.
-------------------------------------------------------------------------------------------------------------------
TEST DESCRIPTION
This test will determine if the wire drive motor and voltage feedback circuit are func-
tioning properly.
MATERIALS NEEDED
5/16 in. Nutdriver
Volt-Ohmmeter
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F-28
F-28
TROUBLESHOOTING & REPAIR
WIRE DRIVE MOTOR AND TACHOMETER FEEDBACK TEST (continued)
FIGURE F.9 — PLUG J1 LOCATION ON G3521 PC CONTROL BOARD.
J6
J5
J3
B
J8
J1
#555
(6J1)
(4J1)
W
(2J1)
#515B
(5J1)
#206B
(1J1)
J4
J2
3. Locate plug J1 on the G3521 control
PC board. See Figure F.9.
TEST PROCEDURE
NOTE: POLARITY MUST BE OBSERVED
FOR THESE TESTS.
4. Locate the following leads on plug J1:
PLUG
LOCATION
Test for Correct Wire Drive Motor Armature
Voltage
LEAD
B
W
4J1
2J1
1. Disconnect main input power to the
machine.
5. Connect the main power to the
machine.
2. Open the side panels and remove the
tool tray using a 5/16 in. nutdriver.
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F-29
F-29
TROUBLESHOOTING & REPAIR
WIRE DRIVE MOTOR AND TACHOMETER FEEDBACK TEST (continued)
6. Make the following voltage tests:
2. Locate plug J1 on the G3521 control
PC board. See Figure F.9.
a. Turn the machine OFF between
each test.
3. Locate the following leads on Plug J1:
b. Carefully insert the meter probes
into the back of each Molex plug
pin cavity to perform the test.
PLUG
LOCATION
LEAD
515B
206B
5J1
1J1
c. Turn the machine ON and pull the
gun trigger to conduct the voltage
test.
4. Connect main input power to the
machine.
FROM
LEAD
TO
LEAD
EXPECTED
VOLTAGE
5. Make the following voltage tests:
B
(4J1)
W
(2J1)
3-20 VDC
(varies depend-
ing on wire feed
speed)
a. Turn the machine OFF between
each test.
b. Carefully insert the meter probes
into the back of each Molex plug
pin cavity.
7. If the voltage to the wire drive motor
armature is zero, check the wires
between plug J1 and the wire drive
motor. Also check the electrical connec-
tor J12 for proper connection and con-
tact.
FROM
LEAD
TO
LEAD
EXPECTED
VOLTAGE
515B
(5J1)
206B
(1J1)
15 VDC
8. If all wires and connectors are good and
the voltage to the drive motor armature
is zero, the G3521 control PC board
may be faulty, replace the control PC
board.
6. If the 15 VDC is present, check the
leads to the tachometer circuit.
7. If the leads are okay and 15 VDC is
present, the correct voltage is being
received from the control PC board,
continue with the Supply Voltage to
Tachometer Test.
9. If the motor is running at high speed
and the armature voltage is high and
uncontrollable, proceed with the
tachometer test.
8. If the 15 VDC is not present and the
leads are okay, the control PC board
may be faulty, replace the control PC
board.
TEST FOR SUPPLY VOLTAGE
TO TACHOMETER
1. Disconnect the main AC input power to
the machine.
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F-30
F-30
TROUBLESHOOTING & REPAIR
WIRE DRIVE MOTOR AND TACHOMETER FEEDBACK TEST (continued)
c. Turn the machine ON and pull the
gun trigger to conduct the voltage
test.
TEST FOR FEEDBACK VOLTAGE
TO CONTROL BOARD
1. Disconnect the main AC input power to
the machine.
FROM
LEAD
TO
LEAD
EXPECTED
VOLTAGE
555
(6J1)
206B
(1J1)
1.5 to 3.5 VDC
2. Locate plug J1 on the G3521 control
PC board.
3. Locate the following leads on plug J1
6. If the 1.5 to 3.5 VDC is present, the
tachometer circuit is sending the cor-
rect feedback signal to the Control PC
Board.
(see Figure F.9):
PLUG
LEAD
LOCATION
555
206B
6J1
1J1
7. If the 1.5 to 3.5 VDC is not present or
not correct, the Control PC Board is
not receiving the proper feedback
voltage from the tachometer circuit.
Check the leads from the tachometer
circuit to the control PC board for loose
or broken connections.
4. Connect main input power to the
machine.
5. Make the following voltage tests:
8. If the leads are okay, the tachometer
circuit may be faulty, replace the
tachometer circuit.
a. Turn the machine OFF between
each test.
b. Carefully insert the meter probes
into the back of each Molex plug
pin cavity.
9. Replace the tool tray.
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F-31
F-31
TROUBLESHOOTING & REPAIR
NORMAL OPEN CIRCUIT VOLTAGE WAVEFORM
0 VOLTS
20.0 V
2.5 ms
SCOPE SETTINGS
This is a typical DC output voltage waveform
generated from
a
properly operating
Volts/Div . . . . . . . . . . . . . . . . . . 20 V/Div
Horizontal Sweep . . . . . . . . . 2.5 ms/Div
Coupling . . . . . . . . . . . . . . . . . . . . . . DC
Trigger . . . . . . . . . . . . . . . . . . . . Internal
machine. Note that each vertical division
represents 20 volts and that each horizontal
division represents 2.5 milliseconds in time.
NOTE:
Scope probes connected at
machine output terminals: (+) probe to elec-
trode, (-) probe to work.
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F-32
F-32
TROUBLESHOOTING & REPAIR
TYPICAL OUTPUT VOLTAGE WAVEFORM - MACHINE LOADED
0 VOLTS
20.0 V
5 ms
MACHINE LOADED TO 250 AMPS AT 26 VDC
SCOPE SETTINGS
This is a typical DC output voltage waveform
generated from properly operating
a
Volts/Div . . . . . . . . . . . . . . . . . . 20 V/Div
Horizontal Sweep . . . . . . . . . . 5 ms/Div
Coupling . . . . . . . . . . . . . . . . . . . . . . DC
Trigger . . . . . . . . . . . . . . . . . . . . Internal
machine. Note that each vertical division
represents 20 volts and that each horizontal
division represents 5 milliseconds in time.
The machine was loaded with a resistance
grid bank.
NOTE: Scope probes connected at machine
output terminals: (+) probe to electrode, (-)
probe to work.
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F-33
F-33
TROUBLESHOOTING & REPAIR
ABNORMAL OUTPUT VOLTAGE WAVEFORM - MACHINE LOADED
ONE OUTPUT SCR NOT FUNCTIONING
0 VOLTS
20.0 V
5 ms
MACHINE LOADED TO 220 AMPS AT 22 VDC
SCOPE SETTINGS
This is NOT a typical DC output voltage
waveform. One output SCR is not function-
ing. Note the increased ripple content. One
SCR gate was disconnected to simulate an
open or non-functioning output SCR. Each
vertical division represents 20 volts and
each horizontal division represents 5 mil-
liseconds in time. The machine was loaded
with a resistance grid bank.
Volts/Div . . . . . . . . . . . . . . . . . . 20 V/Div
Horizontal Sweep . . . . . . . . . . 5 ms/Div
Coupling . . . . . . . . . . . . . . . . . . . . . . DC
Trigger . . . . . . . . . . . . . . . . . . . . Internal
NOTE: Scope probes connected at machine
output terminals: (+) probe to electrode, (-)
probe to work.
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F-34
F-34
TROUBLESHOOTING & REPAIR
ABNORMAL OPEN CIRCUIT VOLTAGE
OUTPUT CAPACITOR BANK NOT FUNCTIONING
0 VOLTS
20.0 V
5 ms
SCOPE SETTINGS
This is NOT the typical DC output voltage
waveform. The output capacitors are not
functioning. Note the lack of “filtering” in the
output waveform. The output capacitor bank
was disconnected. Each vertical division
represents 20 volts and each horizontal divi-
sion represents 5 milliseconds in time.
Volts/Div . . . . . . . . . . . . . . . . . . 20 V/Div
Horizontal Sweep . . . . . . . . . . 5 ms/Div
Coupling . . . . . . . . . . . . . . . . . . . . . . DC
Trigger . . . . . . . . . . . . . . . . . . . . Internal
NOTE: Scope probes connected at machine
output terminals: (+) probe to electrode, (-)
probe to work.
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F-35
F-35
TROUBLESHOOTING & REPAIR
TYPICAL SCR GATE VOLTAGE WAVEFORM
0 VOLTS
2.00 V
5 ms
SCOPE SETTINGS
This is a typical SCR gate pulse voltage
waveform. The machine was in an open
circuit condition (no load) and operating
properly. Note that each vertical division
represents 2 volts and each horizontal
division represents 5 milliseconds in time.
Volts/Div . . . . . . . . . . . . . . . . . . 2.0 V/Div
Horizontal Sweep . . . . . . . . . . 5 ms/Div
Coupling . . . . . . . . . . . . . . . . . . . . . . DC
Trigger . . . . . . . . . . . . . . . . . . . . Internal
NOTE: Scope probes connected at Plug J6
on the control board. The (+) probe to lead
G2, and the (-) probe to lead 204.
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F-36
F-36
NOTES
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F-37
F-37
TROUBLESHOOTING AND REPAIR
CONTROL PC BOARD
REMOVAL AND REPLACEMENT PROCEDURE
WARNING
Service and repair should be performed by only Lincoln Electric factory trained
personnel. Unauthorized repairs performed on this equipment may result in danger
to the technician or machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and pre-
cautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to per-
form the test / repairs safely, contact the Lincoln Electric Service Department for
electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
CAUTION
Printed Circuit Boards can be damaged by static electricity. Follow static handling
guidelines detailed in “PC Board Troubleshooting Procedures” at the beginning of this
chapter.
------------------------------------------------------------------------------------------------------------------
DESCRIPTION
This procedure will aid the technician in the removal and replacement of the Control PC
Board.
MATERIALS NEEDED
5/16 in. Nutdriver
Static electricity grounding strap
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F-38
F-38
TROUBLESHOOTING AND REPAIR
CONTROL PC BOARD
REMOVAL AND REPLACEMENT PROCEDURE (Continued)
REMOVAL AND REPLACEMENT
PROCEDURE
FIGURE F.10 — WIRING HARNESS
AND MOLEX PLUG LOCATIONS.
J6
J5
1. Disconnect main input power the
machine.
2. Open the side panels and remove the
tool tray using a 5/16 in. nutdriver.
J3
3. Disconnect all wiring harness plugs and
Molex plugs connected to the control
board. See Figure F.10.
J8
J1
J4
J2
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F-39
F-39
TROUBLESHOOTING AND REPAIR
CONTROL PC BOARD
REMOVAL AND REPLACEMENT PROCEDURE (Continued)
FIGURE F.11 — CONTROL BOARD MOUNTING.
TOOL
TRAY
MOUNTING
STANDOFF
PC CONTROL
BOARD
NOTE: TOP COVER SHOWN
REMOVED FOR CLARITY.
4. Ensure a static electricity grounding
strap is used before handling the con-
trol PC boards.
7. When re-installing the control PC board
carefully secure board to mounting
standoffs.
5. Carefully remove the control PC board
from the mounting standoffs.
8. Install all plug connectors previously
removed from the control PC board.
6. Lift the control PC board straight up and
out from the machine.
9. Install the tool tray and close the side
panels.
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F-40
F-40
NOTES
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F-41
F-41
TROUBLESHOOTING & REPAIR
WIRE DRIVE ASSEMBLY
REMOVAL AND REPLACEMENT PROCEDURE
WARNING
Service and repair should be performed by only Lincoln Electric factory trained
personnel. Unauthorized repairs performed on this equipment may result in danger
to the technician or machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and pre-
cautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to per-
form the test / repairs safely, contact the Lincoln Electric Service Department for
electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
DESCRIPTION
This procedure will aid the technician in the removal and replacement of the Wire Drive
Assembly.
MATERIALS NEEDED
Large slot head screwdriver
5/16 in. Nutdriver
Small slot head screwdriver
3/4 in. Open end wrench
7/16 in. Nutdriver
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F-42
F-42
TROUBLESHOOTING & REPAIR
WIRE DRIVE ASSEMBLY REMOVAL AND REPLACEMENT (continued)
FIGURE F.12 — WIRE DRIVE ASSEMBLY REMOVAL FOR CODES 10563 & 10583 REFER TO P344-F.2
FOR EXPLODED VIEW OF WIRE DRIVE FOR CODES 10986 AND 10990 - SIMILAR PROCEDURE
2
17
9
4
18
19
3
1. Wire Drive Assembly
2. Motor/Gearbox Assembly
7
3. Flange Nut
4. Positive Lead
5. Hose Clamp
10
16
1
6. Flex Hose
7. Outer Guide Assembly
8. Thumb Screw
8
5
15
9. Adjustment Arm Assembly
10. Idle Arm
11. Round Head Screw
12. Lock Washer
12
6
13
11
14
13. Flat Washer
14. Molded Drive Roll Shaft
Assembly
15. Pan Head Screw
16. Lock Washer
17. Hex Head Cap Screw
18. Lock Washer
19. Flat Washer
6. Disconnect the wire connectors J13
and J12 to the motor/gearbox assem-
bly. See Wiring Diagram.
PROCEDURE
1. Disconnect main input power to the
machine.
7. Use a 3/4 in. wrench and remove the
flange nut and positive lead from the
wire drive assembly. See Figure F.12.
2. Remove the wire gun and wire.
3. Lift the wire drive door to gain access to
the wire drive assembly.
8. Use pliers to remove the hose clamp
and flex hose from the wire drive
assembly.
4. Lift the tool tray door to allow access to
the tool tray.
9. Remove the outer guide assembly from
the wire drive assembly by loosening
the thumb screws until the outer guide
can be removed.
5. Use a 5/16 in. nutdriver and remove the
tool tray to gain access to the
motor/gearbox assembly.
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F-43
F-43
TROUBLESHOOTING & REPAIR
WIRE DRIVE ASSEMBLY REMOVAL AND REPLACEMENT (continued)
10. Rotate the adjustment arm assembly
counterclockwise to release the tension
on the idle arm.
15. Grasp the motor/gearbox assembly and
wiggle the motor/gearbox assembly
gently back and forth until it separates
from the wire drive assembly.
11. Swing the idle arm up and away from
the wire drive assembly.
16. Use a 7/16 in. nutdriver to remove the
hex head cap screws, lock washers,
and flat washers securing the wire
drive assembly to the wire drive
compartment.
12. Use a screwdriver and remove the
round head screw, lock washer, and flat
washer securing the molded drive roll
shaft assembly to the wire drive assem-
bly.
17. Remove the wire drive assembly from
the wire drive compartment.
13. Remove the molded drive roll shaft
assembly and the rest of the outer
guide assembly from the wire drive
assembly.
18. Reassemble the wire drive assembly in
the reverse order.
14. Use a screwdriver and remove the pan
head screws and lock washers secur-
ing the motor/gearbox assembly to the
wire drive assembly.
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F-44
F-44
NOTES
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F-45
F-45
TROUBLESHOOTING & REPAIR
SCR OUTPUT RECTIFIER
REMOVAL AND REPLACEMENT PROCEDURE
WARNING
Service and repair should be performed by only Lincoln Electric factory trained
personnel. Unauthorized repairs performed on this equipment may result in danger
to the technician or machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and pre-
cautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to per-
form the test / repairs safely, contact the Lincoln Electric Service Department for
electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
DESCRIPTION
This procedure will aid the technician in the removal and replacement of the SCR
Assembly.
MATERIALS NEEDED
1/2 in. Open end wrench
1/2 in. Socket wrench, universal tool, and extension
3/8 in. Nutdriver
3/8 in. Open end wrench
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F-46
F-46
TROUBLESHOOTING & REPAIR
SCR OUTPUT RECTIFIER REMOVAL AND REPLACEMENT (continued)
3. Disconnect lead #204 and heavy alu-
minum choke lead from the middle heat
sink with a 1/2 in. socket wrench and
1/2 in. open end wrench. See Figure
F.14.
PROCEDURE
1. Remove the case side panels using a
3/8 in. nutdriver.
2. Disconnect lead #208S and trans-
former lead X1 from the heat sink on
the left side of the machine using a 1/2
in. socket wrench. See Figure F.13.
4. Remove the diode lead from the nega-
tive capacitor band buss bar on the
right side of the machine using a 1/2 in.
socket and 3/8 in. open end wrench.
a. Thin lead is always on the outboard
side of the connection.
FIGURE F.14 — MIDDLE HEAT SINK
LEAD DISCONNECTION.
FIGURE F.13 — LEFT HEAT SINK
LEAD DISCONNECTION.
HEAVY
LEAD
MIDDLE
HEAT SINK
LEAD
#204S
LEFT
HEAT SINK
LEAD X1
LEAD
#208S
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F-47
F-47
TROUBLESHOOTING & REPAIR
SCR OUTPUT RECTIFIER REMOVAL AND REPLACEMENT (continued)
FIGURE F.15 — RIGHT HEAT SINK LEAD DISCONNECTION.
SCR DIODE
LEAD
LEAD
SCR
ASSEMBLY
#320B
LEAD
#320
LEAD
#209S
LEAD
X4
5. Remove lead #209S and transformer
lead X4 from the right side heat sink
using a 1/2 in. socket wrench and
1/2 in. open end wrench. See Figure
F.15.
8. Clear the leads and carefully remove
the SCR rectifier assembly.
NOTE: When installing the SCR rectifier
assembly, apply a thin coating of Dow
Corning #340 compound to the electrical
connections.
6. Unplug the SCR gate leads G1 and G2
(see wire markers and wiring diagram).
9. Unplug leads 320 and 320B from the
SCR heat sink thermostat on the right
side at the SCR assembly.
7. Remove the four nuts holding the SCR
assembly to the floor of the machine
using a 3/8 in. nutdriver.
10. Reassemble the SCR assembly in the
reverse order.
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F-48
F-48
NOTES
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F-49
F-49
TROUBLESHOOTING & REPAIR
CAPACITOR BANK
REMOVAL AND REPLACEMENT PROCEDURE
WARNING
Service and repair should be performed by only Lincoln Electric factory trained
personnel. Unauthorized repairs performed on this equipment may result in danger
to the technician or machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and pre-
cautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to per-
form the test / repairs safely, contact the Lincoln Electric Service Department for
electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
WARNING
The liquid electrolite in the capacitors is toxic. Do not touch the capacitors with
any part of your body.
-------------------------------------------------------------------------------------------------------------------
DESCRIPTION
This procedure will aid the technician in the removal and replacement of the Capacitor
Bank.
MATERIALS NEEDED
5/16 in. Nutdriver
3/8 in. Nutdriver
1/2 in. Open end wrench
3/8 in. Open end wrench
Wiring diagram
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F-50
F-50
TROUBLESHOOTING & REPAIR
CAPACITOR BANK REMOVAL AND REPLACEMENT (continued)
FIGURE F.16 — LOCATION OF CAPACITOR BANK REMOVAL AND REPLACEMENT COMPONENTS.
LEAD
#206
SCR DIODE
LEAD
CAPACITOR
BANK
LEAD
#206B
SHUNT
LEADS
X1 AND X2
POWER
ENHANCEMENT
CHOKE LEAD
OUTPUT
CHOKE LEAD
tive capacitor bank buss bar using a
1/2 in. open end wrench.
PROCEDURE
See Figure F.16 for location of capacitor
bank removal and replacement components.
6. Remove the choke lead and lead 204B
from the positive capacitor bank buss
bar using two 1/2 in. open end wrench-
es.
1. Disconnect main input power to the
machine.
7. Remove the power factor enhancement
choke lead from the positive capacitor
buss bar using two 1/2 in. open end
wrenches.
2. Remove the case side panels using a
3/8 in. nutdriver.
3. Test that the capacitors are discharged
using a volt ohmmeter. Polarity must
be observed.
8. Remove the three nuts holding the
capacitor bank to the floor of the
machine using a 3/8 in. nut driver.
4. Remove the two transformer secondary
leads X2 and X3 (braided copper strap)
from the negative capacitor bank buss
bar using two 1/2 in. open end wrench-
es.
9. Clear the leads and carefully remove
the capacitor bank assembly from the
machine.
10. Reassemble the capacitor bank in the
reverse order.
5. Remove the shunt, leads 206, 206B,
and the SCR diode lead from the nega-
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F-51
F-51
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER AND OUTPUT CHOKE
REMOVAL AND REPLACEMENT PROCEDURE
WARNING
Service and repair should be performed by only Lincoln Electric factory trained
personnel. Unauthorized repairs performed on this equipment may result in danger
to the technician or machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and pre-
cautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to per-
form the test / repairs safely, contact the Lincoln Electric Service Department for
electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
DESCRIPTION
This procedure will aid the technician in the removal and replacement of the Main
Transformer and Choke Assembly.
MATERIALS NEEDED
5/16 in. Nut Driver
1/2 in. Open end wrench
3/8 in. Open end wrench
1/2 in. Socket wrench, extender, universal adapter
Wire cutters
Phillips head screwdriver
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F-52
F-52
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER AND OUTPUT CHOKE
REMOVAL AND REPLACEMENT (continued)
FIGURE F.17 — MAIN TRANSFORMER REMOVAL.
LEAD
X1
OUTPUT
CHOKE
LEAD
OUTPUT
CHOKE
POSITIVE
LEAD
NOTE: PLUG-IN LEADS ARE
NOT SHOWN FOR
CLARITY.
LEAD
X4
LEADS
X2 AND X3
MAIN
TRANSFORMER
POWER
ENHANCEMENT
CHOKE
6. Remove the two transformer secondary
leads X2 and X3 (braided copper strap)
from the negative capacitor bank buss
bar using two 1/2 in. open end wrench-
es.
PROCEDURE
1. Disconnect main input power to the
machine.
2. Remove the case side panels using a
3/8 in. nutdriver.
7. Disconnect and label all transformer
leads from the reconnect panel using a
3/8 in. open end wrench.
3. Test that the capacitors are discharged
using a volt ohmmeter. Polarity must
be observed.
8. Disconnect and label all leads from the
input power switch.
4. Remove lead X1 from the left side SCR
heat sink assembly using a 1/2 in. sock-
et wrench, extender and universal
adapter. See Figure F.17.
9. Remove the power switch.
10. Disconnect thermostat leads #320 and
#320B from the SCR Rectifier.
5. Remove lead X4 from the right side
heat sink assembly using a 1/2 in. sock-
et wrench, extender and universal
adapter.
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F-53
F-53
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER AND OUTPUT CHOKE
REMOVAL AND REPLACEMENT (continued)
11. Unplug and label leads X5, X6, X7, X8, and X9.
These leads have connectors near the trans-
former which can be disconnected.
14. Remove the four nuts and washers mounting the
transformer to the floor of the machine using a
1/2 in. wrench.
12. Disconnect the output choke lead from the posi-
tive capacitor bank buss using two 1/2 in. open
end wrenches.
15. Carefully remove the main transformer and choke
assembly.
16. Reassemble the main transformer and choke
assembly in the reverse order.
13. Remove the other output choke lead from the
positive output terminal using a 1/2 in. wrench.
13. Remove all cable ties, wire mounts, and any har-
ness type that could get in the way during trans-
former removal using wire cutters and screw
driver.
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F-54
F-54
NOTES
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F-55
F-55
TROUBLESHOOTING & REPAIR
FAN MOTOR ASSEMBLY
REMOVAL AND REPLACEMENT PROCEDURE
WARNING
Service and repair should be performed by only Lincoln Electric factory trained
personnel. Unauthorized repairs performed on this equipment may result in danger
to the technician or machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and pre-
cautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to per-
form the test / repairs safely, contact the Lincoln Electric Service Department for
electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
DESCRIPTION
This procedure will aid the technician in the removal and replacement of the Fan Motor
Assembly.
MATERIALS NEEDED
3/8 in. Nutdriver
11/32 in. Open end wrench
Slot head screwdriver
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F-56
F-56
TROUBLESHOOTING & REPAIR
FAN MOTOR ASSEMBLY REMOVAL AND REPLACEMENT (continued)
FIGURE F.18 — FAN MOTOR ASSEMBLY REMOVAL.
FAN
BLADE
LEAD
#353
FAN
BLADE
CLAMP
LEAD
#352
FAN
MOTOR
a. Loosen and remove the two nuts
and lock washers from the motor
mounting bracket using a 11/32 in.
open end wrench.
PROCEDURE
1. Disconnect main input power to the
machine.
b. When the motor is free from the
mounting bracket, slide the motor
from the POWER MIG unit.
1. Remove the case side panels using a
3/8 in. nutdriver.
2. Disconnect the fan motor leads #352
and #352. See Figure F.18.
5. Install the replacement motor in the
reverse order of removal.
3. Remove the fan blade. Note the posi-
tion of the fan on the shaft for reassem-
bly.
6. Install the fan blade and tighten the fan
blade clamp. Ensure the fan is in the
same position on the shaft as it was
prior to removal.
a. Use a screwdriver to loosen the fan
blade clamp.
a. Spin the fan to be sure it is free to
rotate.
b. Slide the fan blade off the motor
shaft.
7. Reassemble the remaining compo-
nents in reverse order of removal.
4. Remove the fan motor.
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F-57
F-57
TROUBLESHOOTING AND REPAIR
RETEST AFTER REPAIR
INPUT IDLE AMPS AND WATTS
Input Volts/Hertz
Maximum Idle Amps
Maximum Idle Watts
230/60
7.0
400
OPEN CIRCUIT VOLTAGE
35-40 VDC
WIRE SPEED RANGE
50 - 700 IPM (1.27 - 17.8 m/minute)
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F-58
F-58
NOTES
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Section G-1
Section G-1
TABLE OF CONTENTS
- ELECTRICAL DIAGRAMS SECTION -
Electrical Diagrams ...............................................................................................Section G
Wiring Diagram - Entire Machine - Code 10563 - (L10979) . . . . . . . . . . . . . . . . . . . .G-2
Wiring Diagram - Entire Machine - Code 10583 - (L10980) . . . . . . . . . . . . . . . . . . . .G-3
Wiring Diagram - Entire Machine - Code 10986 - (L11980) . . . . . . . . . . . . . . . . . . . .G-4
Wiring Diagram - Entire Machine - Code 10990 - (L11979) . . . . . . . . . . . . . . . . . . . .G-5
Control PC Board Schematic (G3520-1D1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-6
Control PC Board Assembly (G3521-1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-7
Display PC Board Schematic (L10951) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-8
Display PC Board Assembly (L10952-1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-9
Snubber PC Board Schematic (S24374) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-10
Snubber PC Board Assembly (M19248-1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-11
POWER MIG 255
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G-2
G-2
ELECTRICAL DIAGRAMS
WIRING DIAGRAM - ENTIRE MACHINE - CODE 10563 - (L10979)
POWER MIG 255 (208/230V)
J10
DISPLAY
BOARD
GENERAL INFORMATION
NOTES:
N.A. WELDING CABLE MUST BE OF PROPER CAPACITY FOR THE
CURRENT AND DUTY CYCLE OF IMMEDIATE AND
FUTURE APPLICATIONS.
ELECTRICAL SYMBOLS PER E1537
COLOR CODE:
CONTROL BOARD
352
1
253
CAVITY NUMBERING SEQUENCE
N.B. THIS DIAGRAM SHOWS THE "ELECTRODE" POLARITY
"POSITIVE". TO CHANGE POLARITY, TURN THE UNIT
OFF AND REVERSE LEAD CONNECTIONS AT CABLE
CONDUCTOR STRAP AND WORK STUD.
252
2
3
4
5
6
(COMPONENT SIDE OF P.C. BOARD)
B
W
R
U
-
BLACK
WHITE
RED
-
251
552
551
256
FAN
-
-
1
1
1
5
3
4
MOTOR
BLUE
1
2
J1
J9
J4
J7
J6
J8
INDICATES CONNECTOR CAVITY NO.
7
8
6
5
4
8
7
6
10
J2
353
550
254
500
9
CAVITY
**
10
6
8
1
1
1
254A
NUMBERING SEQUENCE
11
12
13
14
J3
J2
J5
(NON-LEAD SIDE OF CONNECTOR)
R4
R3
14
9
7
12
8
16
2
1
1
2
515
J11
J13
J12
256
253
254
251
252
J10
J7
1
10
3
4
1
2
390
392
265
263
262
267
264
1
2
ARC
VOLTAGE
WIRE FEED
SPEED
3
3
4
4
5
GAS
SOLENOID
5
6
J4
6
260
7
8
7
8
515B
261
555
9
9
10
10
206B
FOR TIMER
OPTION
B
GUN
TRIGGER
206B
W
W
1
2
J11
**
1
324
325
1
2
3
4
325
324
B
2
J1
515B
555
325
5
6
7
3
4
3
SNUBBER
4
204
1
2
BOARD
208S
208
208R
204S
209S
209
324
8
3
4
5
6
7
8
R.F.
CHOKE
AS’BLY
J9
1
2
390
392
J8
209R
208R
354
D2
J12
SECONDARY VOLTAGES SHOWN
ARE NO LOAD RMS VALUES
BAFFLE
MOUNTED
RECTIFIER
DIODE
**
B
1
209R
X8
X8
SCI
BRIDGE
1
2
116.6V
W
2
X9
X9
X5
X5
325A
543
326
3
4
14.2V
X6
X6
5
6
14.2V
541A
SCI
208S
J3
X7
X7
X1
7
8
9
10
11
12
320
H1
G1
L2
L1
SCR
1
515
206A
320B
325B
28.4V
X2
204S
H3
H4
H2
L1
L2
SCR HEATSINK
ASBLY
OUTPUT CHOKE
THERMOSTAT
SCR HEATSINK
ASSEMBLY
TO SINGLE PHASE
SUPPLY LINE
THERMOSTAT
H2
H3
W
230V
208V
X3
SCR
2
J13
H1
H4
W
**
28.4V
MOTOR/
GEARBOX
515B
555
R
U
B
1
2
T
P.M.
B
G2
X4
A
C
H
H1
209S
RECONNECT
PANEL
206B
3
LINE
SWITCH
S1
POWER
4
G
TRANSFORMER
209
208
206
1
TO GROUND PER
NATIONAL ELECTRICAL
CODE
D1
TO
2
3
4
B
WORK
206S
205
5
6
352
X9
7
8
J5
354
325B
9
10
11
GND
320
207
12
13
14
206
353
X8
15
16
206S 205
207
G2
204
G1
X7
X6
X5
1
2
3
4
206B
204B
15 OHMS
100
J6
C1
C2
C3
W
C1 THRU C3
31,000 MFD
50V
+
+
+
5
6
POWER FACTOR
ENHANCEMENT
CHOKE
OUTPUT
CHOKE
R.F. FILTER
GND
2-23-2001A
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.
POWER MIG 255
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G-3
G-3
ELECTRICAL DIAGRAMS
WIRING DIAGRAM - ENTIRE MACHINE - CODE 10583 - (L10980)
POWER MIG 255 (230/460/575V)
J10
GENERAL INFORMATION
DISPLAY
BOARD
NOTES:
N.A. WELDING CABLE MUST BE OF PROPER CAPACITY FOR THE
CURRENT AND DUTY CYCLE OF IMMEDIATE AND
FUTURE APPLICATIONS.
ELECTRICAL SYMBOLS PER E1537
COLOR CODE:
CONTROL BOARD
CAVITY NUMBERING SEQUENCE
352
1
253
(COMPONENT SIDE OF P.C. BOARD)
N.B. THIS DIAGRAM SHOWS THE "ELECTRODE" POLARITY
"POSITIVE". TO CHANGE POLARITY, TURN THE UNIT
OFF AND REVERSE LEAD CONNECTIONS AT CABLE
CONDUCTOR STRAP AND WORK STUD.
2
3
4
252
B
W
R
U
-
BLACK
WHITE
RED
-
251
FAN
552
1
3
1
4
1
5
-
-
J1
J9
1
2
J4
J7
MOTOR
551
256
5
J6
BLUE
J8
6
INDICATES CONNECTOR CAVITY NO.
6
5
4
8
10
6
353
7
J2
550
8
254
500
6
8
1
1
7
1
9
CAVITY
10
**
254A
NUMBERING SEQUENCE
(NON-LEAD SIDE OF CONNECTOR)
J3
J2
J5
11
12
13
R4
R3
14
9
7
12
8
16
515
2
1
2
14
J11
J13
252
J10
256
253
254
J7
251
10
1
J12
3
4
1
390
392
265
263
262
1
2
1
2
ARC
VOLTAGE
WIRE FEED
SPEED
3
4
3
267
264
260
4
5
GAS
SOLENOID
5
6
J4
6
7
8
9
7
8
9
515B
261
555
10
10
206B
FOR TIMER
OPTION
B
GUN
W
206B
W
1
2
J11
TRIGGER
**
324
325
1
2
1
2
3
4
325
B
515B
555
J1
5
6
7
3
4
3
SNUBBER
324
4
204
208S
208
208R
204S
209S
1
2
325
324
BOARD
8
3
R.F.
4
5
CHOKE
AS’BLY
390
392
J9
1
2
209R
208R
J8
354
6
7
8
D2
J12
SECONDARY VOLTAGES SHOWN
ARE NO LOAD RMS VALUES
BAFFLE
**
209
209R
MOUNTED
RECTIFIER
DIODE
1
B
X8
X8
SCI
325A
1
2
BRIDGE
116.6V
W
2
X9
X9
X5
X5
3
543
326
14.2V
4
5
X6
X6
14.2V
541A
SCI
6
7
208S
X7
X7
X1
J3
320
G1
SCR
H1
L2
8
9
10
11
L1
H2
H4
H3
H1
H5
L1
L2
1
515
206A
320B
325B
28.4V
X2
H2
204S
SCR HEATSINK
ASBLY
H5
5
SCR HEATSINK
ASSEMBLY
OUTPUT CHOKE
THERMOSTAT
12
THERMOSTAT
W
H3
X3
SCR
2
H1
J13
R
H4
**
2
4
28.4V
3
1
MOTOR/
515B
1
2
T
H4
P.M.
X4
G2
GEARBOX
555
U
H1
A
C
H
209S
RECONNECT
PANEL
206B
B
3
4
LINE
SWITCH
S1
POWER
(SHOWN CONNECTED
FOR 230V)
TRANSFORMER
209
208
206
1
TO
2
3
4
D1
B
WORK
W
B
206S
205
TO SINGLE PHASE
SUPPLY LINE
5
6
7
8
9
10
11
352
TO GROUND PER
X9
NATIONAL ELECTRICAL
CODE
J5
354
325B
GND
320
207
12
13
206
14
15
16
353
X8
206S 205
207
G2
204
G1
X7
1
2
206B
204B
3
4
15 OHMS
100
J6
C1
+
C2
+
C3
W
5
6
C1 THRU C3
31,000 MFD
50V
+
X6
X5
POWER FACTOR
OUTPUT
CHOKE
ENHANCEMENT
CHOKE
R.F. FILTER
GND
2-23-2001A
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.
POWER MIG 255
Download from Www.Somanuals.com. All Manuals Search And Download.
G-4
G-4
ELECTRICAL DIAGRAMS
WIRING DIAGRAM - ENTIRE MACHINE - CODE 10986 - (L11980)
POWER MIG 255 (230/460/575 V)
J10
GENERAL INFORMATION
ELECTRICAL SYMBOLS PER E1537
COLOR CODE:
B - BLACK
NOTES:
DISPLAY
BOARD
N.A. WELDING CABLE MUST BE OF PROPER CAPACITY FOR THE
CURRENT AND DUTY CYCLE OF IMMEDIATE AND
FUTURE APPLICATIONS.
CONTROL BOARD
352
CAVITY NUMBERING SEQUENCE
(COMPONENT SIDE OF P.C. BOARD)
1
253
1
N.B. THIS DIAGRAM SHOWS THE "ELECTRODE" POLARITY
"POSITIVE". TO CHANGE POLARITY, TURN THE UNIT
OFF AND REVERSE LEAD CONNECTIONS AT CABLE
CONDUCTOR STRAP AND WORK STUD.
252
251
552
551
256
2
W - WHITE
R - RED
U - BLUE
3
4
5
FAN
MOTOR
1
5
4
1
1
3
6
1
J1
J9
J12
J4
J7
J6
J8
INDICATES CONNECTOR CAVITY NO.
6
7
5
8
6
4
10
2
353
J2
550
254
500
8
9
CAVITY
NUMBERING SEQUENCE
254A
1
6
10
11
12
13
14
1
7
1
8
**
J3
J2
J5
R4
R3
(NON-LEAD SIDE OF CONNECTOR)
16
7
12
9
8
14
515
1
2
4
256
253
254
251 252
J10
J11
J7
10
1
3
390
392
265
263
262
267
264
260
1
2
3
1
2
3
ARC
VOLTAGE
WIRE FEED
SPEED
4
5
6
7
8
9
4
5
GAS
SOLENOID
J4
6
7
261
8
9
10
10
FOR TIMER
OPTION
GUN
TRIGGER
206B
B
1
2
3
J11
**
1
324
325
1
2
325
324
W
2
4
5
6
7
8
J1
515B
555
325
324
3
4
3
4
J12
SNUBBER
BOARD
204
1
2
3
1
2
3
208S
208
R
U
B
515B
555
208R
204S
209S
209
4
5
6
7
8
4
5
6
7
8
390
392
J9
1
2
206B
209R
208R
J8
354
D2
BAFFLE
SECONDARYVOLTAGES SHOWN
ARENO LOAD RMS VALUES
B
B
MOUNTED
RECTIFIER
DIODE
W
W
209R
X8
X8
116.6V
BRIDGE
SCI
325A
543
1
2
3
X9
X9
X5
X5
326
14.2V
X6
4
5
X6
14.2V
X7
X7
X1
541A
SCI
6
208S
J3
7
320
G1
H1
8
L2
L1
H2
H5
H4 H3
H1
L1
L2
SCR 1
515
9
320B
325B
28.4V
X2
206A
10
11
12
W
B
H2
204S
SCR HEATSINK
ASBLY
H5
5
OUTPUT CHOKE
THERMOSTAT
SCR HEATSINK
ASSEMBLY
THERMOSTAT
H3
X3
SCR 2
G2
H1
H4
2
4
28.4V
3
1
R
U
B
WIRE
DRIVE
MOTOR/
GEARBOX
H4
T
X4
A
C
H
H1
209S
RECONNECT
PANEL
(SHOWN CONNECTED
FOR 230V)
LINE
SWITCH
S1
POWER
TRANSFORMER
209
208
206
206S
205
1
2
3
4
5
TO
WORK
D1
W
B
TO SINGLE PHASE
SUPPLYLINE
6
7
G
352
X9
8
TO GROUND PER
NATIONAL ELECTRICAL
CODE
J5
354
325B
GND
320
207
9
10
11
12
13
14
15
16
206
353
X8
206S 205
207
G2
204
G1
X7
X6
X5
1
2
3
206B
204B
15 OHMS
100W
J6
C1 C2 C3
4
5
6
C1 THRU C3
31,000 MFD
50V
+
+
+
POWER FACTOR
ENHANCEMENT
CHOKE
OUTPUT
CHOKE
R.F. FILTER
GND
A
L11980
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.
POWER MIG 255
Download from Www.Somanuals.com. All Manuals Search And Download.
G-5
G-5
ELECTRICAL DIAGRAMS
WIRING DIAGRAM - ENTIRE MACHINE - CODE 10990 - (L11979)
POWER MIG 255 (208/230 V)
J10
GENERAL INFORMATION
NOTES:
DISPLAY
BOARD
N.A. WELDING CABLE MUST BE OF PROPER CAPACITY FOR THE
CURRENT AND DUTY CYCLE OF IMMEDIATE AND
FUTURE APPLICATIONS.
ELECTRICAL SYMBOLS PER E1537
COLOR CODE:
CONTROL BOARD
352
CAVITY NUMBERING SEQUENCE
(COMPONENT SIDE OF P.C. BOARD)
1
253
1
N.B. THIS DIAGRAM SHOWS THE "ELECTRODE" POLARITY
"POSITIVE". TO CHANGE POLARITY, TURN THE UNIT
OFF AND REVERSE LEAD CONNECTIONS AT CABLE
CONDUCTOR STRAP AND WORK STUD.
252
251
552
551
256
2
B - BLACK
W - WHITE
R - RED
3
4
5
FAN
MOTOR
1
5
4
1
1
3
6
1
U - BLUE
J1
J9
J12
J4
J7
J6
J8
INDICATES CONNECTOR CAVITY NO.
6
7
5
8
6
4
10
2
353
J2
550
254
500
8
9
CAVITY
NUMBERING SEQUENCE
254A
1
6
10
11
12
13
14
1
7
1
8
**
J3
J2
J5
R4
R3
(NON-LEAD SIDE OF CONNECTOR)
16
7
12
9
8
14
515
1
2
4
256
253
254
251 252
J10
J11
J7
10
1
3
390
392
265
263
262
267
264
260
1
2
3
1
2
3
ARC
VOLTAGE
WIRE FEED
SPEED
4
5
6
7
8
9
4
5
GAS
SOLENOID
J4
6
7
261
8
9
10
10
FOR TIMER
OPTION
GUN
TRIGGER
206B
B
1
2
3
J11
**
1
324
325
1
2
325
324
W
2
4
5
6
7
8
J1
515B
555
325
324
3
4
3
4
J12
SNUBBER
BOARD
204
1
2
3
1
2
3
208S
208
R
U
B
515B
555
208R
204S
209S
209
4
5
6
7
8
4
5
6
7
8
390
392
J9
1
2
206B
209R
208R
J8
354
D2
BAFFLE
SECONDARYVOLTAGES SHOWN
ARENO LOAD RMS VALUES
B
B
MOUNTED
RECTIFIER
DIODE
W
W
209R
X8
X8
116.6V
BRIDGE
SCI
325A
543
1
2
3
X9
X9
X5
X5
326
14.2V
X6
4
5
X6
14.2V
X7
X7
X1
541A
SCI
6
208S
J3
7
320
H1
G1
8
L2
L1
SCR 1
515
9
320B
325B
28.4V
X2
206A
10
11
12
W
B
204S
H3
H4
H2
L1
L2
SCR HEATSINK
ASBLY
TO SINGLE PHASE
SUPPLY LINE
OUTPUT CHOKE
THERMOSTAT
SCR HEATSINK
ASSEMBLY
THERMOSTAT
H2
230V 208V
X3
SCR 2
G2
H1
H4
W
B
28.4V
R
U
B
WIRE
T
X4
DRIVE
MOTOR/
GEARBOX
A
C
H
H1
209S
RECONNECT
PANEL
H3
POWER
TRANSFORMER
LINE
SWITCH
S1
G
209
208
206
206S
205
1
2
3
4
5
TO
WORK
TO GROUND PER
NATIONAL ELECTRICAL
CODE
D1
6
7
352
X9
8
J5
354
325B
GND
320
207
9
10
11
12
13
14
15
16
206
353
X8
206S 205
207
G2
204
G1
X7
X6
X5
1
2
3
206B
204B
15 OHMS
100W
J6
C1 C2 C3
4
5
6
C1 THRU C3
31,000 MFD
50V
+
+
+
POWER FACTOR
ENHANCEMENT
CHOKE
OUTPUT
CHOKE
R.F. FILTER
GND
A
L11979
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.
POWER MIG 255
Download from Www.Somanuals.com. All Manuals Search And Download.
G-6
G-6
ELECTRICAL DIAGRAMS
CONTROL PC BOARD SCHEMATIC - (G3520-1D1)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available
from Lincoln Electric. This information is provided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the
Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
POWER MIG 255
Download from Www.Somanuals.com. All Manuals Search And Download.
G-7
G-7
ELECTRICAL DIAGRAMS
CONTROL PC BOARD ASSEMBLY - (G3521-1)
3 5 2 G 1 - 1
ITEM
REQ’D
PART NO.
IDENTIFICATION
S16668-5
C1,C2,C8,C9,C14,C20,C29
18
.022/50
C36,C37,C38,C39,C43,C44
C48,C52,C53,C55,C56
C3,C4,C11
C5,C6,C18,C19,C35,C51,C54
C7
S13490-42
T11577-52
S13490-73
S16668-11
3
7
1
16
1.0/35
.0047 OR .005/1400
20/50
.1/50
C10,C22,C23,C24,C25,C30
C31,C32,C33,C34,C40,C41
C45,C46,C57,C58
C12,C13
C15
C16
C17,C28
C26
S16668-1
S13490-30
S13490-92
S13490-39
T11577-28
S13490-118
S16668-7
S13490-76
S13490-102
S24833-1
T12199-2
2
1
1
2
1
1
1
1
1
1
4
22pF/100
39/10
3300/50
18/15
.22/100
C27
C47
C49
C50
2200/63V
820pF/50
.001/400
.047/100
C59
D1,D2,D3,D31
D4,D5,D6,D7,D8,D9,D10,D11,D12,D13,D14, 31
D15,D16,D17,D18,D19,D20,D21,D22,D24
D25,D26,D27,D28,D29,D30
0.27/63V
1N4007
1N4004
~.04
T12199-1
6.00
D32,D33,D34,D35,D36
T12705-23
T12702-40
T12702-45
S18248-8
S18248-14
S18248-12
S24020-10
S18248-16
S18248-6
S18248-2T
T12218-7
S15000-30
S15000-31
T12704-68
S18105-4
D23,D37
DZ1
DZ2,DZ3,DZ4
J1
J2
J3
J4
J5
2
1
3
1
1
1
1
1
1
1
4
2
1
5
1
2
2
1
11
1N5818
1N4735
R34
R40
5.80
1N4746A
HEADER
HEADER
HEADER
HEADER,VERTICAL
HEADER
HEADER
HEADER
330uH
R104
C38
J6
J8
L1,L2,L3,L4
OCI1,OCI2
OCI3
Q1,Q2,Q3,Q6,Q11
Q4
Q5,Q9
Q7,Q10
Q8
R1,R2,R6,R41,R42,R65,R75
R79,R84,R112,R113
R3,R7,R25,R26,R114,R117
R4,R51
OPTOCOUPLER TRIAC DRIVER 800V
C36
D24
C37
C39
OPTOCOUPLER,TRIACDRV,RANDOM,800V
2N4401
HEATSINK ASBLY
NPN TRANSISTOR
TRANSISTOR,NMF,T220,45A,100V(SS)
T12704-35
T12704-88
T12704-69
S19400-1002
R41
C12
2N4403
10K 1/4W
Q6
Q8
XXXXXXXXXXXXX
S24002-1200
S19400-1502
S19400-4751
R110
R111
6
2
8
120 2.5W
15K 1/4W
4.75K
XXX
C13
R5,R9,R12,R30,R35,R45,R70
R90
R8,R115
R10,R11,R62,R63,R76,R77
4.75K
1.21K 1/4W
100 1/4W
7/16W
Q11
S19400-1211
S19400-1000
2
10
C53
X2
R78,R82,R95,R105
R13,R22,R93,R94
R14,R15,R23,R27
R18,R20,R24,R80
R19,R21,R58,R83
R28,R46,R61
R29,R100,R110
R31,R106
R32
R33,R37,R38
R34,R40
R36
1.21K 1/4W
681 1/4W
15 1/4W
O C I 3
S19400-6810
S19400-15R0
S19400-5620
S19400-2211
S19400-6811
S19400-1501
S19400-5621
S19400-2672
S19400-2212
S19400-33R2
S19400-2671
S19400-3321
4
4
4
4
3
3
2
1
3
2
1
7
562 1/4W
2.21K 1/4W
6.81K 1/4W
1.5K 1/4W
R108
R109
C52
XXXXXXXXXXXXXXX
D32
C45
R82
R12
D30
R96
5.62K 1/4W
26.7K 1/4W
22.1K 1/4W
33.2 1/4W
Q5
2.67K 1/4W
3.32K 1/4W
R39,R68,R71,R72,R91,R92
R111
R43
R44,R109
R47
R48
R49,R50
R52,R98
R53
R54
R55,R56
R57,R108
R59,R66,R69,R73,R74,R86,R87
R60
R64,R67
R81
R88,R89
R96,R103
R97
S19400-1004
S19400-1001
S19400-1301
S19400-2801
T14648-22
S19400-3011
S19400-5111
T12300-75
S19400-26R7
S19400-2670
S19400-4422
S19400-2432
S19400-5110
T14648-5
S19400-1622
S19400-4752
T14648-19
S19400-1652
S19400-1372
S19400-7500
S19400-4750
S19400-2802
T13640-15
T13640-9
T13640-18
S15161-27
S24392-4
M15102-3
S17900-8
S15128-11
S15128-16
S23060-1
S15018-4
S15018-6
1M 1/4W
1K 1/4W
1.3K 1/4W
2.8K 1/4W
50 5W
1
2
1
1
2
2
1
1
2
2
7
1
2
1
2
2
1
1
2
1
1
1
2
2
1
1
1
1
1
2
1
1
1
1
2
1
1
DZ4
R99
3.01K 1/4W
.25 OHM, 7W RESISTOR
5.11K 1/4W
26.7 1/4W
D28
267 1/4W
44.2K 1/4W
24.3K 1/4W
.20
511 1/4W
3.3K 5W
16.2K 1/4W
47.5K 1/4W
1K 5W
R99
16.5K 1/4W
13.7K 1/4W
750 1/4W
475 1/4W
28.0K 1/4W
15J
20J
MOV,120J
T2500D
ROM ASSEMBLY (SS)
0
R101,R102
R104
R107
R116
TP1,TP2
TP3,TP4
TP7
TRI1
X1
X2
X3
X4,X5
X6
X7
X8
X9
X10,X11
X12
Y1
~.04
9.00
0
.20
3.20
8.80
IC,S8054HN,CMOS,UNDERVOT-SENSING(SS)
14 PINI.C.(SS)
14 PIN QUAD COMPARATOR
IC,LT1014,LINEAR INTEGRATED CIRCUIT
IC,SWITCH,LO-SIDE(SS)
MC14584(SS)
DIGITAL INTEGRATED CIRCUIT(SS)
IC,431,VOLTAGE REF.
S15128-10
S15128-5
S16665-5
+5V REG.
8.0 MHZ
Ch’ge. Sht. No.
11-16-2001D
EQUIP.
TYPE
POWER MIG 255
THE LINCOLN ELECTRIC CO.
CLEVELAND, OHIO U.S.A.
A
XE-RW
3-12-99
CONTROL P.C. BOARD ASSEMBLY
SUBJECT
7-9-99H
FULL
SCALE
7-28-2000J
10-5-2001C
SHT.
G2803-1
C.S./
12-18-98
3521-1
REF.
G
DR
DATE
CHK
SUP’S’D’G
NO.
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available
from Lincoln Electric. This information is provided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the
Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
POWER MIG 255
Download from Www.Somanuals.com. All Manuals Search And Download.
G-8
G-8
ELECTRICAL DIAGRAMS
DISPLAY PC BOARD SCHEMATIC - (L10951)
500
16
15
3
7
6
5
4
2
a
BANK4
X3
3
8
BANK3
Vdd
b
c
d
3
8
3
8
1
1
1
2
4
5
6
7
9
2
4
5
6
7
9
2
4
5
6
7
9
13
9
BANK2
BANK1
e
17
12
11
19
14
h
BANK5
DATA IN
CLOCK
DISP3
DISP2
DISP1
Vss
10
10
10
20
1
g
10
18
f
/ENABLE
8
DATA OUT
Rx
MC14489
500
J10
LATCH
13
12
1
2
4
R10
X5
X5
475
C9
.0047
50V
500
J10
SCK
5
11
10
R9
X5
475
C8
.0047
50V
500
16
7
6
5
4
2
a
BANK4
BANK3
X4
500
3
8
15
3
b
c
d
3
8
3
8
1
1
1
Vdd
2
4
5
6
7
9
2
4
5
6
7
9
2
4
5
6
7
9
13
9
J10
MOSI
6
BANK2
BANK1
BANK5
VOLTS
LED3
9
8
R8
X5
e
475
17
12
10
11
19
14
h
C7
.0047
50V
DISP7
DISP6
DISP5
DATA IN
/ENABLE
CLOCK
Vss
10
10
10
20
1
g
500
f
18
8
DATA OUT
MC14489
Rx
500
R1
221
500
R2
221
R13
221
+5VA
D1
R3
221
3
3
R4
Vdd
Vdd
14
221
J10
X5
C3
0.1
50V
X1
X3
X4
7
5
3
6
4
R14
221
C10
0.1
50V
C4
0.1
50V
515
X5
X5
IN
OUT
7805
HEXINV
MC14489
MC14489
C1
GND
C2
18
15V
4.7
Vss
Vss
14
14
35V
7
J10
8
500
500
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available
from Lincoln Electric. This information is provided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the
Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
POWER MIG 255
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G-9
G-9
ELECTRICAL DIAGRAMS
DISPLAY PC BOARD ASSEMBLY - (L10952-1)
ITEM
REQ’D
IDENTIFICATION
PART NO.
C1
C2
1
1
3
3
1
6
S13490-25
S13490-39
S16668-11
S16668-6
T12199-1
S17395-2
4.7/35
18/15
.1/50
4700pF/50
1N4004
DISPLAY
C3,C4,C10
C7,C8,C9
D1
DISP1,DISP2,DISP3,DISP5
DISP6,DISP7
J10
LED3
1
1
6
3
3
2
1
2
1
S20380-8
T13657-6
RT ANGLE HEADER
RED LED
221 1/4W
10K 1/4W
475 1/4W
1.5K 1/4W
+5V REG.
R1,R2,R3,R4,R13,R14
S19400-2210
S19400-1002
S19400-4750
S19400-1501
S15128-5
R5,R6,R7
R8,R9,R10
R11,R12
X1
X3,X4
X5
S20496-1
S17900-8
IC,MC14489,CMOS,DRIVER,LED,CC,MCU(SS)
14 PIN I.C. (SS)
~.04
1.64
1.44
DISP3
DISP2
DISP1
DISP7
DISP6
DISP5
R12
C9
C8
R9
R6
J10
.49
C10
C4
0
~.04
5.80
0
.20
2.90
5.60
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available
from Lincoln Electric. This information is provided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the
Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
POWER MIG 255
Download from Www.Somanuals.com. All Manuals Search And Download.
G-10
G-10
ELECTRICAL DIAGRAMS
SNUBBER PC BOARD SCHEMATIC - (S24374)
2 4 3 S 7 4
J1
J1
J1
J1
J1
J1
J1
J1
1
204
208S
2
3
4
5
6
7
8
C1
.68
400V
208
5W
10
208R
204S
209S
209
5W
10
C2
.68
400V
209R
NOTES :
LABELS
GENERAL INFORMATION
N.A.
SINCE COMPONENTS OR CIRCUITRY ON
CIRCUIT BOARD MAY CHANGE
A PRINTED
ELECTRICAL SYMBOLS PER E1537
FRAME CONNECTION
WITHOUT AFFECTING
SUPPLY
VOLTAGE NET
CAPACITORS =
MFD
(
.022/50V
1/4W UNLESS OTHERWISE SPECIFIED)
(UNLESS OTHERWISE SPECIFIED)
UNLESS OTHERWISE SPECIFIED)
THE INTERCHANGEABILITY
OF A COMPLETE
SHOW THE EXACT COMPONENTS
CONTROLS HAVING A COMMON CODE NUMBER.
BOARD.
POWER SUPPLY SOURCE POINT
COMMON CONNECTION
RESISTORS = Ohms (
THIS DIAGRAM MAY NOT
EARTH GROUND CONNECTION
OR CIRCUITRY OF
DIODES =
1A, 400V
EQUIP.
TYPE
Ch’ge.Sht.No.
POWERMIG 255
THE LINCOLN ELECTRIC CO.
CLEVELAND, OHIO U.S.A.
NONE
XB-RW
SNUBBER BOARD
SUBJECT
3-12-99
SCALE
SHT.
5-12-98
MAB
DR.
DATE
CHK.
SUP’S’D’G.
NO.
S
24374
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available
from Lincoln Electric. This information is provided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the
Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
POWER MIG 255
Download from Www.Somanuals.com. All Manuals Search And Download.
G-11
G-11
ELECTRICAL DIAGRAMS
SNUBBER PC BOARD ASSEMBLY - (M19248-1)
1 9 2 M 4 8 - 1
REQ’D
IDENTIFICATION
ITEM
PART NO.
C1,C2
J1
R1,R2
2
1
2
T11577-68
S18248-8
T14648-25
0.68 MFD /400 WVDC CAPACITOR
HEADER
10 5W
.20
1.80
~.04
4.00
3.80
SNUBBER
M19248-1
J1
R1
CAPACITORS = MFD/VOLTS
R2
C2
C1
.20
0
~.04
0
2.00
Ch’ge. Sht. No.
XB
EQUIP.
TYPE
SP WELDERS
THE LINCOLN ELECTRIC CO.
CLEVELAND, OHIO U.S.A.
3-12-99
SNUBBER P.C. BOARD AS’BLY
SUBJECT
1-12-2001D
A
SCALE
FULL
5-13-98
SHT.
M16647-1
REF.
R.T.
DR
19248-1
DATE
CHK
SUP’S’D’G
M
NO.
B
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available
from Lincoln Electric. This information is provided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the
Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
POWER MIG 255
Download from Www.Somanuals.com. All Manuals Search And Download.
SVM ERROR REPORTING FORM
We need to know if there are errors in our manuals. We also value any suggestions as to
additional tests or procedures that would make this SVM a better tool for you.
If you discover new or different “Problems or Symptoms” that are not covered in the three col-
umn troubleshooting chart, please share this information with us. Please include the
machine’s code number and how the problem was resolved.
Thank You,
Technical Services Group
Lincoln Electric Co.
22801 St. Clair Ave.
Cleveland, Ohio 44117-1199
FAX 216-481-2309
SVM Number ___________________________
Page Number if necessary__________________
Your Company__________________________
Your Name_____________________________
Please give detailed description below:
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
SD287 04/06
Download from Www.Somanuals.com. All Manuals Search And Download.
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