GENERATOR SET CONTROLS REPAIR INSTRUCTIONS
Section I. INTRODUCTION
3-2. Generator Set Controls Description.
This chapter includes repair instructions for the
The generator set controls are mounted at the rear
fault indicator panel and the control cubicle. Test
of the set, and provide all monitoring and control
procedures for the control cubicle include individual
devices required to operate the set. Controls con-
tests for the converter, control box, relay assem-
sist of the fault indicator panel, the control cubicle,
bly, frequency meter and transducer, ac wattmeter
and the manual throttle control.
Refer to the Oper-
and ac ammeter.
ator and Organizational Maintenance Manual for
manual throttle control repair instructions.
FAULT INDICATOR PANEL
3-3. Removal, Disassembly and Repair,
a. Removal. Refer to Operator and Organiza-
tional Maintenance Manual and remove the fault indi-
b. Disassembly. See figures 3-1 and 3-2 and
disassemble the fault indicator panel.
c. Repair. Proceed as follows
(1) Clean all components with low pressure
compressed air, or wipe clean with dry, lint free
(2) Inspect for broken fuseholders, cracked or
broken lamp holders, damaged wire insulation, bro-
den wires and bent or broken connector pins.
(3) Remove any components that show visual
damage, such as broken fuseholder, or broken lamp
holder (fig. 3-1).
(4) Replace circuit board if broken, cracked
(5) Resistors may be checked by breaking con-
nection at one end to prevent feedback resistance
and touching both ends with ohmmeter probes. Re-
sistors R1 through R10 (fig. 1-2) should read 2. 2K
ohms ±10 percent.
Resistors R11 through R20
should read 1K ohms ±10 percent. Any variation
in excess of 10 percent indicates that the resistor
should be replaced.
If any connections are opened
or bared for test purposes or if any defective com-
ponents are replaced, the affected area must be
coated with polyurethane resin to prevent oxidation
or other corrosion. The coating must be of a mini-
mum thickness of O. 007 inches and air bubble entry
into the applied polyurethane must be controlled so
that the legibility of component coding and identifica-
tion is not impaired.
The polyurethane resin to be
utilized will correspond to MIL-I-46058 grade S,
(6) Unplug relay 17, (fig. 3-1) in fault indica-
tor panel and check resistance of relay coils with
ohmmeter probes across pins 3 and 7. Reading
should be 300 ohms ±10 percent. Replace relay if
variation exceeds 10 percent. Plug relay into cir-
(7) Rebuild wiring harness if inspection re-
veals 30 percent or more defective wires. Wiring
harness rebuilding instructions are described in
Chapter 5. Otherwise replace damaged wires.
3-4. Reassembly, Testing and Installation.
a. Reassembly. See figures 3-1 and 3-2 and re-
assemble the fault indicator panel.
b. Testing. See figure 1-2. To test the fault in-
dicator panel, proceed as follows:
(1) Connect 24Vdc, positive to pin A of ter-
(2) Connect 24Vdc negative to pin B and case.
(3) Operate reset switch. All lights should
(4) Connect pin C to pin D. Low oil pressure
light should light.
(5) Open C to D connection. Low oil pressure
lights should remain on.
(6) Connect pin C to pin E. Low oil pressure
light should remain on.
(7) Operate reset switch. Low oil pressure
light should go out and overspeed switch should light.