ARMY TM 9-6115-464-12
AIR FORCE TO 35C2-3-445-1
NAVY NAVFAC P-8-624-12
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BATTLE DAMAGE. Unit maintenance troubles may occur while the generator set is operating in the field
where supplies and repair parts are not available and normal corrective action cannot be performed. When this condi-
tion exists, refer to the Battle Damage Assessment and Repair manual TM 9-6115-624-BD.
Section VI. RADIO INTERFERENCE SUPPRESSION
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GENERAL METHODS USED TO OBTAIN PROPER SUPPRESION. Essentially, suppression is obtained
by providing a path to ground for stray currents. The methods used include shielding high frequency wires, grounding
the frame with bonding straps, and using capacitors, inductors and resistors.
4-11 INTERFERENCE SUPPRESSION COMPONENTS.
a.
Primary Interference Suppression Components. The primary interference components are those whose
primary function is the suppression of electromagnetic interference. Those components are located at three
different assemblies. The assemblies are the exciter regulator, the load terminal board, and are an integral
part of the fuel transfer pumps. The suppression components located on the load terminal board and the
exciter regulator are effective for generator sets designed serial number KZ00001 and RZ60001 and up.
b. Secondary Interference Suppression Components. These components have radio interference suppression
functions which are incidental or secondary to their primary function. The generator set contains no secondary
suppression components.
4-12 TESTING OF INTERFERENCE SUPPRESSION COMPONENTS. Test radio suppression components as
follows:
a.
b.
c.
d.
e.
f.
g.
Place START-RUN-STOP switch (paragraph 2-6) in RUN position and allow fuel transfer pumps to run until
day tank float switch cuts them off.
Start the generator set (paragraph 2-6) and check for electromagnetic interference.
If interference is present, and the fuel transfer pumps are not operating, the transfer pumps are not the source.
If interference is not present, allow the generator set to operate until the day tank float switch turns the fuel
transfer pumps on.
If interference is present with fuel transfer pumps operating, shutdown the generator set (paragraph 2-7)
and replace the pumps.
If the foregoing test indicates interference is caused by defective components other than those within the
fuel pumps, replace one at a time, each of the four capacitors on the load terminal board assembly while
observing the effect on interference.
If the above tests do not eliminate the interference, the fault may be in the exciter regulator. Refer to higher
level maintenance.
Section VIl. UNIT MAINTENANCE OF THE ENGINE ELECTRICAL SYSTEM
4-13 GENERAL
This section contains unit maintenance instructions for the engine electrical system. Electrical power for starting the
generator set engine is supplied by two 12 volt, 100 amp-hour, lead-acid type batteries connected in series. A slave
receptacle facilitates external connection to the batteries. The starting motor is a 24 volt, heavy duty unit equipped
with a positive indexing drive and an overrun type clutch. An integral solenoid switch is connected to the clutch shift
lever by linkage and engages the clutch pinion gear with the flywheel and holds it in mesh during engine cranking.
A 28-volt, continuous duty, alternator with integral voltage regulator and diode rectifier supplies electrical power for
recharging the batteries after cranking. A manually reset speed switch driven by the camshaft provides sequence
control of circuits during starting and also provides automatic shutdown in the event of engine overspeeding.
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