ARMY TM 9-6115-673-13&P
AIR FORCE TO 35C2-3-512-1
(5). Set multimeter for DC volts and connect positive lead of multimeter to terminal 9 of TB1 and
negative lead to terminal 1 of TB1. Multimeter should indicate 27-29 VDC. If reading is incorrect,
check wiring between CB1-P1 (Line) and TB1. Then redo step 5.
(6) Connect positive lead of multimeter to terminal 3 of TB1 and negative lead to terminal 1 of
TB1. Multimeter should indicate 35-45 VDC.
(7) Connect positive lead of multimeter to terminal 5 of TB1 and negative lead to terminal 1 of
TB1. Multimeter should indicate 35-45 VDC. If reading is incorrect, check LOP solenoid (L4) and
wiring between solenoid and TB1. Then redo step 7.
(8) Connect positive lead of multimeter to terminal 4 of TB1 and negative lead to terminal 1 of
TB1. Multimeter should indicate 18-22 VDC.
(9) Connect positive lead of multimeter to terminal 8 of TB1 and negative lead to terminal 1 of
TB1. Multimeter should indicate 0-1 VDC with ON-OFF load circuit breaker CB1 in OFF position.
With CB1 in ON position, multimeter should indicate 35-45 VDC.
NOTE
At generator set startup, generator control (A2) momentarily applies current
to field flash the alternator (G2). It can therefore be assumed that if the
alternator is producing power, this function of A2 is satisfactory. However, if
it is suspected that there is no field flash current for the alternator (G2),
check A2 as follows.
(10) Shutdown diesel engine. Disconnect A2-VINDC at terminal 9 of TB1 and A2-F at terminal
10 of TB1. Connect positive lead of multimeter to disconnected A2-F wire and negative lead to
terminal 1 of TB1. Then start diesel engine. Multimeter should indicate 35-45 VDC. Shutdown
diesel engine and reconnect wires to terminals 9 and 10 of TB1.
(11) Start generator set.
(12) Apply a ground to LOP switch terminal. Diesel engine should stop.
CAUTION
The following steps are the only way to check the short circuit function of
the generator control unit without special test equipment. If the ON-OFF
load circuit breaker closes and does not open instantaneously,
IMMEDIATELY open it manually.
Electrical circuitry and component
damage could occur in less than a second if short circuit function is
inoperative.
(13) With diesel engine stopped, connect a piece of 4 AWG electrical wire across output load
terminals. Loop wire so as to avoid contact with the generator set frame.
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