1---4
1
2
3
1. Pre---cleaner
2. Ejected dust
3. Duralife filter
Figure 1---3. Engine Air Cleaner
1.7 OPERATING CONTROLS AND
INSTRUMENTS
Components required for monitoring and controlling
the unit are located in the control box and control panel
(See Figure 1---2)
The water temperature safety switch (HWT) is
located near the thermostat housing.
1.7.2Control Panel and Related Components
a. A---C Voltmeter
The a---c voltmeter is a sealed and ruggedized device
indicating the line---to---line voltage output from the
main alternator on a scale of 0 to 600 volts. When the unit
has an output of 460 vac, the indicating needle will be in
the green band. (Refer to paragraph 4.3.4.)
b. Total Time Meter
This meter designates the total hours and provides an
accurate readout of accumulated engine running time.
This data can be used to establish the proper periodic
maintenance schedule. (Refer to paragraph 4.1)
c. Frequency Meter and Interference Filter ---
Optional
The meter and filter are used to monitor the hertz of
the A---C generator output. This meter will read 60 hz,
when the correct engine speed is obtained. (Refer to
paragraph 4.3.4)
d. Ammeter
The ammeter indicates the rate of discharge or charge
of the battery charging system composed of the battery,
battery charging alternator and the voltage regulator.
e. Gauges and Senders
1. Oil Pressure Gauge
The purpose of this gauge is to observe normal
operating engine oil pressure. Normal oil pressure is 40 to
60 psig (2.8 to 4.2 kg/cm
@
).
2. Oil Pressure Sender
This sensing device senses engine lube oil pressure
and transmits a signal to the oil pressure gauge. The oil
pressure sensor is located in the oil line near the oil
pressure switch.
3. Water Temperature Gauge
The function of this gauge is to observe water
operating temperature (180 to 205
_
F = 82 to 94
_
C). The
gauge is connected to a water temperature sensing
device.
If the gauge or sender fails, both must be replaced (kit
available).
4. Water Temperature Sender
This sensing device senses engine water temperature
and transmits a signal to the water temperature gauge.
The water temperature sender is located on the top,
front, right side of the engine below the HWT switch. The
water temperature gauge and sender both must be
replaced if either component fails (kit available).
f. Indicator Light
1. Circuit Breaker Trip Light
This light (red) may be checked (unit not running) by
placing the circuit breaker (CB) in the off position and at
the same time moving the ignition switch to the run
position. When the circuit breaker is in the off position, a
set of contacts close to complete a circuit to the light.
If the unit is running and the circuit breaker trips, the
light will illuminate to signal the operator of a malfunc-
tion with the generator.
g. Switches
1. Glow Plug Switch
The glow plug switch (momentary contact type), when
held in the UP position (pre---heat), permits battery
current (approximately 7.5 amps per plug at 12 vdc) to
flow to the glow plugs in the engine to pre---heat the
combustion chambers. The glow plugs are located under
the fuel injectors. When starting engine, it is necessary to
continue to hold the glow plug switch in the UP position
until the engine has developed sufficient oil pressure to
close the oil pressure safety switch.
2. Ignition Switch
The ignition switch (momentary contact type in the
start position), when held in the START (ignition)
position energizes the starter motor solenoid which in
turn allows the starter motor to crank.
1.7.3 Protective Devices
a. Oil Pressure Switch
This switch, set to open below 15 psig (1.05 kg/cm
@
)
will automatically stop the engine upon loss of oil
pressure. This switch is located on the right side of the
engine. (See Figure 1---1) When the switch opens, the
run control relay (RCR) coil is de---energized and the
RCR contacts open to de---energize the fuel solenoid
(FS); thus stopping the engine.
b. High Water Temperature Switch
This switch, set to open at 230
¦
5
_
F (110
¦
3
_
C),
will automatically stop the engine upon high water
temperature. The switch is located near the thermostat
housing. When the switch opens, the run control relay
(RCR) coil is de---energized and the RCR contacts open
to de---energize the fuel solenoid (FS); thus stopping the
engine.
c. A---C Generator Circuit Breaker (CB---1)
This device trips at 25 amps to protect the A---C
generator (main alternator) from excessive current
(amperage) draw. When the circuit breaker trips, the
generator power output to the refrigeration unit ceases.
The diesel engine will continue to run (with normal
engine operation), but the voltmeter will indicate no
output and the circuit breaker indicator light will be
illuminated.
d. Circuit Breaker (CB---2)
The circuit breaker is located in the control box. This
device prevents excessive current draw by the compo-
nents RCR, FS, TT, OPG, WTG, L1 and HWT. The
