Lincoln Electric CLASSICII SVM125-A Service Manual page 55

F-5
TROUBLESHOOTING GUIDE
PROBLEMS
(SYMPTOMS)
The engine starts and runs at cor-
rect speed, but there is no, or very
low, welder output voltage. The AC
auxiliary output voltage is normal.
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 for loose, damaged or
missing brushes in the welding
generator.
2. Check the welding cables for
loose or faulty connection.
CAUTION
CLASSIC II
Observe Safety Guidelines
detailed in the beginning of this manual.
RECOMMENDED
COURSE OF ACTION
1. Check the
Adjustment rheostat for resis-
tance and proper operation.
Normal resistance is 64 ohms.
Check associated wires for
loose or faulty connections.
See the Wiring Diagram.
2. Perform the
Winding Test.
3. Check the continuity of the inter-
pole coils. They should show
continuity from the positive
brusholders to the positive out-
put terminal and should NOT be
grounded to the generator
frame.
4. Check the continuity of the
series coils. They should show
continuity from the negative
brusholders,
Current Range selector switch,
to the negative output terminal
and should NOT be grounded.
Also check the Selector Switch
for proper operation.
5. The main armature may be
faulty. Check for grounds and/
or shorts.
F-5
Fine Current
Shunt Field
through the