Troubleshooting Guide - Lincoln Electric SHIELD-ARC SVM128-A Service Manual

F-4
Observe Safety Guidelines
detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
The engine starts and runs at cor-
rect speed, but there is no, or very
low, welder output voltage. There
is no AC auxiliary output voltage.
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)
OUTPUT PROBLEMS
1. Check the 15 amp fuse located
on the inside of the front control
panel.
2. If the welder output is zero volts,
the fields may need to be
See Flashing the
flashed.
Fields in this section.
3. Check for loose or missing
brushes in the exciter alternator
and welding generator.
CAUTION
SA-250

TROUBLESHOOTING GUIDE

RECOMMENDED
COURSE OF ACTION
1. Check the "flashing" diode and
associated leads connected
between the generator brushes
and the exciter alternator brush-
es.
2. Check the field diode bridge and
associated leads and connec-
tions. See the Wiring Diagram.
3. Perform the Alternator Rotor
Test.
4. Check for "opens" or shorted
turns in the alternator stator
windings. The coils must NOT
be grounded to the stator lami-
nation.
F-4