Troubleshooting Guide - Lincoln Electric INVERTEC STT Series Service Manual

F-4
Observe Safety Guidelines
detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
Major physical or electrical damage
is evident.
Machine has no open circuit volt-
age. Wire feeds OK.
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. Contact your local Lincoln
Authorized
Facility.
1. Check the
between the feeder and the
STT unit. Make sure the #2 and
#4 leads are intact.
2. Put a jumper wire between Pins
"C" and "D" on the 14 pin
amphenol. If normal open cir-
cuit voltage
restored, the problem is in the
feeder control cable or the wire
feeder.
3. Make sure the reconnect switch
S7 is in the correct position for
the three-phase input voltage
being applied.
CAUTION
Do not switch reconnect switch
with input power
machine.
CAUTION
INVERTEC STT

TROUBLESHOOTING GUIDE

RECOMMENDED
COURSE OF ACTION
1. Contact the Lincoln Electric
Field Service Service Department, 216-383-
2531 or 1-800-833-9353 (WELD).
control cable 1. Perform
Transformer Test.
2. Perform
Transformer Test.
3. Perform the Power Board Test.
4. Perform the Trigger Circuit
Test.
(85VDC) is
5. Perform Capacitor Balance
Test.
6. Perform the Protection Board
Test.
7. Perform the Switch Board
Test.
8. Check for loose or broken con-
nections on the heavy current
carrying conductors (i.e., main
transformer,
applied to diodes, Darlington module and
output terminals).
9. The control PC board may be
faulty. Replace.
F-4
the T1 Auxiliary
the T4 Auxiliary
choke, output