Lincoln Electric SVM138-A Service Manual page 86

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TROUBLESHOOTING GUIDE
PROBLEMS
(SYMPTOMS)
Voltage seems to be too high or the
arc flares at the start of weld.
Welding is good.
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
216-383-2531 or 1-800-833-9353.
TROUBLESHOOTING & REPAIR
POSSIBLE AREAS OF
MISADJUSTMENT(S)
STARTING PROBLEMS
1. Adjust the "start" trimmer on the
voltage PC board. It should be
only slightly higher than the weld
voltage. See Starting Charac-
teristics in the Operation section
of this manual.
2. Put the Lincoln power source in
the "Machine Control" mode.
Jumper the "BYPASS" pins on
the LN-9 GMA voltage PC
board. Adjust the weld voltage
from the power source for the
process being used. If the cor-
rect voltage cannot be set, the
power source may be faulty.
3. Check for correct control cable
connections to the power supply.
CAUTION
LN-9 GMA Wire Feeder
Observe Safety Guidelines
detailed in the beginning of this manual.
RECOMMENDED
COURSE OF ACTION
1. The LN-9 GMA voltage PC
board may be faulty. Replace.
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