Lincoln Electric LN-9 SVM127-A Service Manual page 78

F-20
TROUBLESHOOTING GUIDE
PROBLEMS
(SYMPTOMS)
The output voltage is too low to
start the weld.
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. Check the welding cables for
loose or faulty connections.
2. Put the Lincoln power source in
the "Machine Control" mode.
Jumper the "BYPASS" pins on
the LN-9 voltage PC board.
Adjust the weld voltage from the
power source for the process
being used. If the correct volt-
age cannot be set, the power
source may be faulty.
3. Check for correct control cable
connections
source.
4. The control cable may be faulty.
Check or replace.
5. The start trimmer on the LN-9
voltage PC board may be set too
low. See Starting Characteris-
tics in the Operation section of
this manual.
CAUTION
LN-9 Wire Feeder
detailed in the beginning of this manual.
RECOMMENDED
COURSE OF ACTION
1. Check
potentiometer (R3) and the
associated leads.
Wiring Diagram.
2. The voltage PC board may be
faulty. Replace.
to the power
F-20
Observe Safety Guidelines
the voltage control
See the