Lincoln Electric INVERTEC V300-I Service Manual page 50

F-7
Troubleshooting Guide
components. See Schematic Diagram for troubleshooting of specific circuits.
PROBLEMS
(SYMPTOMS)
Poor welding, weld settings drift, or
output power is low.
Poor stick electrode performance.
Arc pops out.
Machine makes "squealing" noise
while under load when welding.
Output power is low (less than 20
VDC on meter @ 100 amps). Input
voltage 230 VAC or lower.
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact the Lincoln
Electric Service Department for technical troubleshooting assistance before you proceed call 216-383-2531 or 1-800-833-9353.
INVERTEC V300-I
TROUBLESHOOTING & REPAIR
— See Wiring Diagrams for location of specified
POSSIBLE AREAS OF
MISADJUSTMENT(S)
WELDING PERFORMANCE PROBLEMS
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 output welding cables.
Is electrode DRY? Try welding with
another electrode from a different
container.
Make sure you have the correct
electrode for your application.
Check input lines and connections.
Check input voltage and reconnec-
tion procedures.
CAUTION
Observe Safety Guidelines
detailed in the beginning of this manual.
POSSIBLE AREAS OF
MALFUNCTION(S)
1. Check Mode Switch S2 for
damage and continuity.
2. Check for continuity between
Mode Switch S2 and Control
Board. See schematic drawing.
3. Check for loose or faulty con-
nections in heavy current-carry-
ing leads (i.e., choke, shunt,
output bridge, and output
studs). See wiring diagram.
4. Check overcurrent protection
on Control Board. Refer to
Overcurrent Protection Current
Trigger Circuit tests. Also refer
to Control Board test.
1. Check for loose or burned con-
nections at choke, shunt, and
output studs. See wiring dia-
gram.
2. Test and inspect D6, D12, L1
and L2. See schematic draw-
ing.
1. See Switch Board test.
2. See Snubber Resistor test.