Lincoln Electric INVERTEC SVM129-B Service Manual page 65

F-27
TEST POINTS
+PROBE
9
9
9
A
B
C
12
12
12
A
B
C
6. Replace the input rectifier when any of the
tests are NOT OK.
NOTE: When installing a new input rectifier,
torque the mounting nuts (in a cross-tightening
pattern) to 6 inch-pounds (.7 Nm). Torque ter-
minals to 26 inch-pounds (3 Nm). PROCEED
TO STEP 7 TO CHECK RELATED COMPO-
NENTS.
7. Inspect main power switch S1 and replace
if faulty. Go to step 8.
TROUBLESHOOTING & REPAIR
INPUT RECTIFIER TEST (continued)
TABLE F.3 – INPUT RECTIFIER TEST
-PROBE
A
B
C
9
9
9
A
B
C
12
12
12
INVERTEC STT
ACCEPTABLE METER READING
Greater than 100K ohms
Greater than 100K ohms
Greater than 100K ohms
Less than 100 ohms
Less than 100 ohms
Less than 100 ohms
Less than 100 ohms
Less than 100 ohms
Less than 100 ohms
Greater than 100K ohms
Greater than 100K ohms
Greater than 100K ohms
8. Test capacitors C1 and C2 and replace both
capacitors if either is faulty.
NOTE: Faulty capacitors could be the reason
for input rectifier failure.
Visually inspect the capacitors for leakage,
damage, etc., and use appropriate test equip-
ment to determine component integrity.
9. Perform the Switch Board Test.
10. After all tests are completed, install the
case wraparound cover.
F-27