TM 9-4910-663-34
Table 2-5. TROUBLESHOOTING (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Step 26. Set circuit breaker switch CB1 to OFF position. Disconnect leads from one coil terminal of relay K7.
Using ohmmeter, check for relay K7 coil resistance between 60.3 and 70.4 ohms. Then reconnect
leads.
Replace relay K7 if coil resistance is not as specified.
Step 27. Set LOAD SELECTION 50 AMPS/25 AMPS switch S20 to OFF position. Set LOAD SELECTION
100
AMPS/50 AMPS switch S19 to ON position. With circuit breaker switch CB1 set to ON position,
check for 0.285 ohm ±5% resistance indication between REGULATOR B+ and REGULATOR B-
binding posts, using ohmmeter.
If resistance is not as specified, proceed to step 28; if resistance is normal, proceed to step 30.
Step 28. Set LOAD SELECTION 100 AMPS/50 AMPS SWITCH S19 to OFF position. Using ohmmeter,
check for 1.14 ohm ±5% indication between REGULATOR B- binding post and each of load bank
terminals 9, 10, 11, and 12.
If any indication is not as specified, replace load bank element.
Step 29. Using ohmmeter, check for continuity across each set of contacts of LOAD SELECTION 100
AMPS/50 AMPS switch S19 with switch S19 set to ON position.
If open indication is obtained for any set of switch contacts, replace switch S19.
Step 30. Set LOAD SELECTION 100 AMPS/50 AMPS switch S19 to OFF position. Set LOAD SELECTION
100 AMPS/50 AMPS switch S18 to ON position. With circuit breaker switch CB1set to ON position,
check for 0.285 ohm ±5% resistance indication between REGULATOR B+ and REGULATOR B-
binding posts, using ohmmeter.
If resistance indication is not as specified, proceed to step 31; if resistance indication is normal,
proceed to step 33.
Step 31. Set LOAD SELECTION 100 AMPS/50 AMPS switch S18 to OFF position. Using ohmmeter, check
for 1.14 ohm ±5% indication between REGULATOR B- binding post and each of load bank terminals
5, 6, 7, and 8.
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