Troubleshooting & repair, Caution – Lincoln Electric POWER MIG 255 SVM144-B User Manual
Page 44
POWER MIG 255
TROUBLESHOOTING & REPAIR
F-6
F-6
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.
TROUBLESHOOTING GUIDE
Observe Safety Guidelines
detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
The output voltage and wire feed is
present continuously or pulsing
when gun trigger is NOT activated.
The output voltage is present contin-
uously when gun trigger is NOT acti-
vated.
1.
Remove the gun. If the problem
is resolved the gun trigger circuit
is faulty. Repair or replace.
2.
If problem persists when gun
assembly is removed from
machine, then the problem is
within the POWER MIG 255.
Contact your local Lincoln Electric
Authorized Field Service Facility.
1.
Check the machine's internal
trigger leads for grounds or
shorts. See Wiring Diagram.
2.
The control board may be faulty.
Replace.
1.
Perform the SCR Rectifier
Assembly Tests.
2.
The control board may be faulty.
Replace.
OUTPUT PROBLEMS (Continued)