ARMY TM 9-6115-641-24
AIR FORCE TO 35C2-3-456-12
1-12-6-1. The Engine Air Intake and Exhaust System (Figure 1-7) consists of an air cleaner assembly, intake manifold,
two heater plugs, exhaust manifold, and muffler. The air cleaner assembly includes a dust collector, filter element, and
restriction indicator.
1-12-6-2. Air is drawn into the dust collector and Passes through the filter element. Airborne dirt is removed and trapped
in the dust collector and filter element. The restriction indicator indicates when the filter should be serviced. Filtered air
is drawn out of the filter through air intake tubes to the intake manifold where it passes into the engine.
1-12-6-3. The engine exhaust gases are expelled into the exhaust manifold. The exhaust manifold channels the gases
into the muffler that deadens the sound of the exhaust gases. The gases pass from the muffler through the muffler outlet
and are vented upward from the generator set housing. A cover, which is held open by the pressure of the exhaust gases
during operation, doses over the exhaust port to prevent rain, water, or other foreign matter from entering the exhaust
port when the set is not in use. The cover is easily removed for connection of an exhaust pipe for indoor operation.
1-12-64. To improve engine starting when ambient temperature is below 40°F (4°C), two heater plugs are located in
the intake manifold. The heater plugs are energized through the preheat relay when the MASTER SWITCH is held in the
PREHEAT position.
1-12-6-5. The DC control circuit provides power to the preheat relay and heater plugs.
1-12-7. Output Supply System.
1-12-7-1. The Output Supply System (Figure 1-8) consists of the AC generator, AC voltage reconnection switch,
GROUND FAULT CIRCUIT INTERRUPTER (GFCI), CONVENIENCE RECEPTACLE, current transformer, AC circuit in-
terrupter relay, load terminals, AC CIRCUIT INTERRUPTER switch, AM-VM transfer switch, AC voltmeter (VOLTS AC),
ammeter (PERCENT RATED POWER), frequency transducer, and FREQUENCY meter (HERTZ).
1-12-7-2. Power created by the AC generator is supplied through the current transformer, AC voltage reconnection
switch, and AC circuit interrupter relay to the load terminals. The AC voltage reconnection switch allows configuration of
the generator set for the following voltage connections: 120 volt, single phase, 2 wire; 120/240 volt, single phase, 3 wire;
and 120/208 volt, 3-phase, 4 wire. The AC generator also provides 120 VAC to the CONVENIENCE RECEPTACLE
through the GROUND FAULT CiRCUiT INTERRUPTER.
1-12-7-3. The AC CIRCUIT INTERRUPTER switch doses and opens the AC circuit interrupter relay. This enables or
interrupts the power flow between the AC voltage reconnection switch and the load terminals. The voltage regulation sys-
tem (refer to paragraph 1-12-10) senses generator output voltage 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), sensed by the frequency transducer and is read on the FREQUENCY meter (HERTZ). The
current transformer provides a reduced current signal to the ammeter (PERCENT RATED CURRENT) which indicates
the percent of rated current being supplied to the load. The position of the AM-VM transfer switch selects the Ioad terminal
from which current and voltage are measured. The AC circuit interrupter relay will open and disconnect the load whenever
an overload or short circuit occurs.
1-16
1-12-6. Engine Air Intake and Exhaust System.
