TM 5-6115-434-12
(2)
Visually inspect for burned, bent, loose, corroded or otherwise damaged connector pins and terminals.
Inspect insulation for burns, chafing, and deterioration. Inspect wiring for breaks, loose connections, or other obvious
damage. Replace all damaged parts.
c.
Repair. Replace damaged wires, terminals, connectors, and receptacles by unsoldering connections, installing
replacement part and soldering in accordance with Military Specification MIL-S-6872 using SN60 solder that conforms to
Federal Specification QQ-S-571.
Note
Refer to figures 1-17 through 1-20 for wire connection points and routing.
d.
Test. Check continuity of wires using a multimeter or continuity light. Refer to figures 1-17 through 1-20 for wire
routing. Continuity must be indicated through individual wires.
e.
Installation. Install wiring harness assemblies, terminals, electrical leads, wiring, connectors, and receptacles in
reverse order of removal procedures.
3-61. Upper Rack Assembly (fig. 3-19)
Note
Access to upper rack assembly is obtained by removing the gas turbine engine power plant
access panel (fig. 1-2). Tag or otherwise identify electrical connections as removed to facilitate
assembly.
a.
Voltage Regulator (60 Hz).
(1)
Removal. Tag and disconnect wiring harness connector plug from the voltage regulator. Remove four
nuts, sixteen washers, and four screws. Remove regulator.
(2)
Cleaning and Inspection.
(a)
Clean voltage regulator with filtered compressed air or wipe with a clean rag moistened with an
approved cleaning solvent. Clean receptacle with filtered compressed air or an electricians brush.
(b)
Visually inspect regulator for corrosion, cracks, damaged threads, or other evidence of damage.
(3)
Test. Start the power unit as described in paragraph 2-14. Operate the 60 Hz electrical system as
described in paragraph 216a. With the 60 Hz electrical system operating, disconnect plug (P32) from voltage regulator
(VR2). Using an adjustable potentiometer, apply 24v ac through a 50 watt resistor into pins J and E on plug (P32).
Adjust potentiometer until voltage begins to increase on panel AC voltmeter (fig. 2-19). If load contactor trip indicator
lamp illuminates, reset load contactor switch (fig. 2-19) and increase voltage to 120v ac line to neutral. If 120 volts are
obtainable and load contactor switch will remain in reset position regulator has failed.
(4)
Installation. Install in reverse order of removal procedure.
b.
Voltage Regulator (400 Hz).
(1)
Removal. Tag and disconnect wiring harness connector plug from -the voltage regulator. Remove four
screws and eight washers. Remove regulator.
(2)
Cleaning and inspection.
(a)
Clean voltage regulator with filtered compressed air or wipe with a clean rag moistened with an
approved cleaning solvent. Clean receptacle with filtered compressed air or an electricians brush.
(b)
Visually inspect regulator for corrosion, cracks, damaged threads or other evidence of damage.
(3)
Test. Start the power unit as described in paragraph 2-14. Operate the 400 Hz electrical system as
described in paragraph 216b. With the 400 Hz electrical system operating, disconnect plug (P30) from voltage regulator
(VR1). Using an adjustable potentiometer, apply 24v ac through a 50 watt resistor into pins J and E on plug (P30).
Adjust potentiometer until voltage begins to increase on panel AC voltmeter (fig. 2-20). If main contactor trip indicator
lamp illuminates, reset main contactor switch (fig. 2-20) and increase voltage to 120v ac line to neutral. If 120 volts are
obtainable and main contactor switch will remain in reset position, regulator has failed.
(4)
Installation. Install in reverse order of removal procedures.
c.
Relay Assembly (two used).
(1)
Removal. Tag and disconnect wiring harness connector plug from the relay assembly. Remove six screws
and twelve washers. Remove relay.
(2)
Cleaning and inspection.
(a)
Clean relay assembly with filtered compressed air or wipe with a clean rag moist
3-68
