Lincoln Electric SHIELD-ARC SVM128-A Service Manual page 73

F-19
FIELD SHUNT WINDING TEST (continued)
6. Using the volt/ohmmeter set on the low
scale (X1), measure the resistance
between the blue and the brown leads.
See Figure F.5.
approximately 50 ohms.
7. Also measure the resistance from either
lead (blue or brown) to ground. Set the
volt/ohmmeter on the high scale (X100,000).
This resistance should be at least 500,000
ohms.
8. If the test does not meet the resistance
specifications, then check the harness plug
and inline connectors for loose connec-
tions or shorted leads.
TROUBLESHOOTING & REPAIR
FIGURE F.5 – SHUNT LEAD RESISTANCE CHECK
PIN 5
TAB
Normal resistance is
SA-250
PIN 3
9. If the plug and associated leads are okay,
then the shunt field coils may be faulty.
Replace.
10. If the test does meet the resistance specifi-
cations, then the shunt coils are okay.
11. Replace plug P10, making sure the leads
and plug are secure.
12. Close and latch the right side door.
F-19