E-3
TROUBLESHOOTING
E-3
TCV400
Observe all Safety Guidelines detailed throughout this manual
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your
Local TAFA Authorized Field Service Facility
for technical troubleshooting assistance before you proceed.
CAUTION
PROBLEMS
(SYMPTOMS)
POSSIBLE
CAUSE
RECOMMENDED
COURSE OF ACTION
Machine has low output and no con-
trol.
Machine does not have maximum
output.
Machine will not shut off.
Erratic Current.
1. Open in feedback circuitry.
2. Faulty Control PC Board.
1. One input fuse blown.
2. One phase of main transformer
open.
3. Faulty Control PC Board.
1. Input contactor contacts frozen.
2. Defective Power “
I/O
”
switch, (S1).
1. Poor work or electrode connec-
tion.
2. Welding leads too small.
3. Welding current or voltage too
low.
4. Defective main SCR bridge.
1. Check wiring and control PC
Board wiring harness plugs.
2. Replace. See Procedure for
Replacing PC Boards.
1. Check and replace if blown after
checking for reason for blown
fuse.
2. Check for open and repair.
3. Replace. See Procedure for
Replacing PC Boards.
1. Check and replace if necessary.
2. Replace.
1. Check and clean all connections.
2. Check table in instruction manual.
3. Check procedures for recom-
mended settings.
4. Check and replace if defective.
Summary of Contents for TCV400
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