Lincoln Electric INVERTEC V300-PRO SVM105-B Service Manual page 38

F-8
TROUBLESHOOTING GUIDE
PROBLEMS
(SYMPTOMS)
Meter reads low voltage (1-2 VDC),
and output is extremely low or no
output.
Poor welding, weld settings drift, or
output power is low.
Welding "too hot". Actual weld cur-
rent is considerably higher than dis-
play indicates.
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 & REPAIR
POSSIBLE AREAS OF
MISADJUSTMENT(S)
FEEDING PROBLEMS
Local/Remote Switch must be in
LOCAL position unless Remote
Control device is attached to remote
receptacle.
Check welding procedures and weld
cable connections.
Check with machine on local con-
trol.
Check input voltages and input volt-
age reconnect procedures. See
Installation section of this manual.
Check condition of the shunt and
leads to the Control Board.
CAUTION
V300-PRO
Observe Safety Guidelines
detailed in the beginning of this manual.
RECOMMENDED
COURSE OF ACTION
1. See Output Diodes test.
2. See Capacitor Balance tests.
3. See Switch Board test.
4. See Power Board test.
5. See Control Board test.
1. Check Mode Switch S2 for dam-
age and continuity.
2. Check for continuity between
Mode Switch S2 and Control
Board. See Wiring Diagram in
Section G.
3. Check for loose or faulty con-
nections in heavy current-carry-
ing leads (i.e., choke, shunt,
output bridge,
studs). See wiring diagram in
Section G.
4. See Overcurrent Protection
Current Trigger Circuit tests.
5. See Control Board test
See Step 7 of the Overcurrent
Protection Current Trigger test
If shunt and leads check OK, possi-
ble defective Control Board
F-8
and output