TM 9-4910-663-34
Table 2-5. TROUBLESHOOTING (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
LOAD & STARTER OUTPUT CURRENT BATTERY CHARGE CURRENT RANGE switch S14, DC
AMMETER FIELD CURRENT RANGE switch S30, and AC AMMETER OUTPUT CURRENT
RANGE switch S26 set as in step 1. Leave phone jack connected as in step 1. Set AC AMMETER
OUTPUT CURRENT SELECT switch S25 to T2 position. Connect test lead from positive DC
VARIABLE VOLTS OUTPUT binding post to ALTERNATOR T2 binding post, and connect another
test lead between rectifier chamber T2 binding post to REGULATOR B+ binding post. Make certain
that DC VARIABLE POWER SUPPLY 0-32 VDC control T5 is set fully counterclockwise. Set circuit
breaker switch CB1 to ON position. Set LOAD SELECTION 0-25 AMPS/ 0-12.5 AMPS switch S24 to
ON. Set MASTER LOAD DISCONNECT switch S8 to ON position. Set DC VARIABLE VOLTS
switch S10 to ON position, and adjust DC VARIABLE POWER SUPPLY 0-32 VDC control slowly to
provide 20 volt indication on DC VOLTMETER OUTPUT VOLTAGE meter M2. Adjust VARIABLE
LOAD control R32 slowly to provide 14 ampere indication on DC AMMETER LOAD & STARTER
OUTPUT CURRENT BATTERY CHARGE CURRENT meter M3. (It may be necessary to readjust
DC VARIABLE POWER SUPPLY 0-32 VDC control T5 to obtain 14 ampere indication.) Check to
see that pointers of AC AMMETER OUTPUT CURRENT meter M5 and DC AMMETER FIELD
CURRENT meter M7 deflect slightly when MASTER LOAD DISCONNECT switch S8 is set of OFF
position, and when switch S8 is set back to ON position. Repeat check with AC AMMETER
OUTPUT CURRENT RANGE switch S26 set to X5 position.
If either meter shows slight deflection in only one position of AC AMMETER OUTPUT
CURRENT RANGE switch, replace switch S26. If neither meter shows slight deflection, perform
continuity check of circuit associated with transformer CT2 and AC AMMETER OUTPUT
CURRENT SELECT switch S25, using ohmmeter; replace defective parts.
Step 3.
Set circuit breaker switch CB1 to OFF position. Leave DC VOLTMETER OUTPUT VOLTAGE
SELECT switch S11, DC VOLTMETER OUTPUT VOLTAGE RANGE switch S12, DC AMMETER
LOAD & STARTER OUTPUT CURRENT BATTERY CHARGE CURRENT RANGE switch S14, DC
AMMETER FIELD CURRENT RANGE switch S30, and AC AMMETER OUTPUT CURRENT
RANGE switch S26 set as in step 1. Leave phone jack connected
2-54
