ARMY TM 9-6115-643-24
AIR FORCE TO 35C2-3-445-22
1.12.7.2
Power created by the generator is supplied through the current transformer, AC voltage reconnection board,
and AC circuit interrupter relay to the output terminals. The AC voltage reconnection board allows configuration of the
generator set for 120/208 volt connections or 240/416 volt connections. The AC CIRCUIT INTERRUPTER switch closes
and opens the AC circuit interrupter relay. This enables or interrupts the power flow between the voltage reconnection
board and the output terminals. The voltage regulation system (refer to paragraph 1.12.10) senses generator output volt-
age and provides a control signal to the generator exciter to maintain the desired generator output voltage. Generator
output frequency is controlled by the governor control system (refer to paragraph 1.12.9) and is read on the FREQUENCY
meter (HERTZ). The current transformer provides a reduced current signal to the kilowatt transducer and ammeter (PER-
CENT RATED CURRENT). The kilowatt transducer and kilowattmeter (PERCENT POWER) provide an indication of the
power being used by the load. The ammeter (PERCENT RATED CURRENT) indicates the percent of rated current being
supplied to the load. The position of the AM-VM transfer switch selects the output terminals from which current and voltage
is measured. The AC circuit interrupter relay will open and disconnect the load whenever any of the following faults occur:
reverse power, undervoltage, overload, or short circuit.
1.12.7.3
The AC generator also provides 120 VAC power to the CONVENIENCE RECEPTACLE through the
GROUND FAULT CIRCUIT INTERRUPTER.
1.12.8
Generator Set Controls.
1.12.8.1
Engine Starting System.
1.12.8.1.1
Engine starting is accomplished primarily with two 12-volt batteries, connected in series to provide 24 VDC
power, and a starter (FIGURE 1-9). The starter includes a cranking motor and a solenoid. To permit engine starting, the
DC CONTROL POWER circuit breaker must be pushed in, the DEAD CRANK switch must be in the NORMAL position,
and the BATTLE SHORT switch must be in the OFF position. In addition, any ENGINE SHUTDOWN fault previously regis-
tered on the malfunction indicator panel must have been corrected and the malfunction indicator panel must have been
reset. When the MASTER SWITCH is then placed in the START position, the starting circuits supply 24 VDC power to
the starter. As the engine accelerates to approximately 900 rpm, the starting circuits disconnect power from the starter.
1.12.8.1.2
When the MASTER SWITCH is first moved to the START position, the various instrument and control cir-
cuits are energized. The Engine Starting System includes two control circuits. One starting control circuit energizes the
start relay through closed switch contacts of the engine fault relay and the BATTLE SHORT switch. The other starting
control circuit energizes the cranking relay coil through closed contacts of the crank disconnect switch and the start relay.
(The crank disconnect switch is an integral part of the electronic governor control.)
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