Lincoln Electric POWER MIG SVM165-A Service Manual page 52

F-6
Observe Safety Guidelines
detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
Wire feeds but welding output is low
causing wire to "stub". Welds are
"cold". Machine cannot obtain full
rated output of 350 amps at 32
volts.
The output voltage and wire feed is
present continuously or pulsing
when gun trigger is NOT activated.
The output voltage is present con-
tinuously when gun trigger is NOT
activated. The wire is not feeding.
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely,
contact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call
1-888-935-3877.
TROUBLESHOOTING & REPAIR
POSSIBLE AREAS OF
MISADJUSTMENT(S)
OUTPUT PROBLEMS
1. Make sure that the proper wire
and procedures are being used.
2. Check gun and work cable for
loose or faulty connections.
1. Remove the gun. If the problem
is resolved, the gun trigger cir-
cuit is faulty. Repair or replace.
2. If problem persists when gun
assembly is removed from
machine, then the problem is
within the POWER MIG 350MP.
CAUTION
POWER MIG 350MP
TROUBLESHOOTING GUIDE
RECOMMENDED
COURSE OF ACTION
1. Check for loose or faulty connec-
tions of the heavy current carry-
ing leads. See Wiring Diagram
2. Perform the Current Transducer
Test.
3. Perform Output Waveform Test.
4. Perform the Output Rectifier
Assembly Tests
5. The Control Board may be faulty.
Replace.
1. Find J85 on Feed Head Board
and unplug. If the problem still
exist Feed Head Board may be
faulty.
1. Find J6 on Control PCB and
unplug. If output voltage is not
present change Control PCB
2. Perform the Chopper Board
Test.
F-6