Lincoln Electric INVERTEC SVM129-B - Manual (Page 73)

TROUBLESHOOTING & REPAIR
F-35 F-35
INVERTEC® STT® & STT® II
SWITCH BOARD TEST (continued)
Apply Positive Apply Negative
Test Probe to
Test Probe to
Terminal Terminal Test Result Conclusion Repair Action Next Procedure Notes
1/8 12 Greater than OK None Continue
1K ohm
Less than Shorted Replace both Snubber Test
100 ohms switch boards
12 1/8 Less than OK None Continue
100 ohms
Greater than Open Replace both Snubber Test
1K ohm switch boards
9 4/5 Greater than OK None Continue
1K ohm
Less than Shorted Replace both Snubber Test
100 ohms switch boards
4/5 9 Less than OK None Continue
100 ohms
Greater than Open Replace both Snubber Test
1K ohm switch boards
1/8 9 Less than OK None Continue
100 ohms
Greater than Open Replace both Snubber Test
1K ohm switch boards
9 1/8 Greater than OK None Continue
1K ohm
Less than Shorted Replace both Snubber Test
100 ohms switch boards
12 4/5 Less than OK None Continue
100 ohms
Greater than Open Replace both Snubber Test
1K ohm switch boards
4/5 12 Greater than OK None Continue
1K ohm
Less than Shorted Replace both Snubber Test
100 ohms switch boards
Continued . . .
NOTE: K ohm = ohm reading multiplied by 1000.
NOTE: Always make sure that switch boards are changed in matched pairs. Never mix an old style (different
part number) switch board with a new switch board (new part number).
TABLE F.5 – SWITCH BOARD RESISTANCE TEST
Return
to
Section
T
OC
Return
to
Section
T
OC
Return
to
Section
T
OC
Return
to
Section
T
OC
Return
to
Master
T
OC
Return
to
Master
T
OC
Return
to
Master
T
OC
Return
to
Master
T
OC