TM 5-6115-434-12
(1)
Removal. Unscrew connector cover from connector plug. Remove four nuts, sixteen washers and four
screws from connector plug. Push connector plug back through mounting bulkhead. Tag and disconnect electrical
connections to connector plug. Remove connector plug.
(2)
Cleaning and inspection.
(a)
Clean connector plug with filtered compressed air and electricians brush or wipe with a clean rag
lightly moistened with an approved cleaning solvent.
(b)
Visually inspect connector plug for corrosion, cracks, damaged threads and inserts or other evidence
of damage.
(3)
Installation. Install in reverse order of removal procedures.
3-64. 400 Hz Generator (fig. 3-22)
Warning
Electrical power to the gas turbine engine shall be disconnected before starting maintenance on
generator.
Note
Access to generator is obtained by removing the gas turbine engine power plant access door.
a.
Removal.
(1)
Release clamp on inlet air duct hose. Remove inlet air duct hose and clamp from inlet air cover.
(2)
Release generator terminal cover from generator terminal board. Tag and disconnect generator electrical
connections on terminal board. Tag and disconnect wiring harness connector from generator.
(3)
Release clamp on generator exhaust chamber assembly hose. Remove exhaust chamber hose and clamp
from exhaust chamber.
(4)
Release clamp between generator and exhaust chamber assembly. Remove clamp from generator.
(5)
Remove four screws and washers from upper half of exhaust chamber. Remove both sections of exhaust
chamber.
Note
Note position of generator terminal board and inlet air cover to aid in positioning generator at
installation.
(6)
Loosen twelve mounting nuts on generator mounting flange. Rotate generator counterclockwise slightly to
allow large opening of mounting holes on mounting flange to pass through mounting nuts. Remove generator from
mounting flange. Warning: Have suitable hosting or support equipment attached to generator an injury to personnel and
equipment may result if hoisting is attempted without required equipment.
b.
Test.
(1)
Start the power unit as described in paragraph 2-14. Operate the 400 Hz electrical system as described in
paragraph 2-16b. 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 ea 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 not
obtainable 400 Hz generator has failed.
(2)
With the power unit not operating, disconnect plug (P31) from the 400 Hz generator. Use a multimeter and
check resistance across receptacle J31 pins AB, AC, and BC. Each check should indicate an equal resistance of 0.8
ohms. If resistance is otherwise, permanent magnet generator (P,-MG) has failed, and generator shall be replaced.
Check resistance across pins D + and E- which shall be 5.0 ohms. Check resistance across pins E + and D- which shall
be 4.0 ohms. If resistance is otherwise, exciter field has failed, and generator shall be replaced.
3-65. 60 Hz Generator (fig. 3-22)
Notes
400 Hz generator shall be removed to provide access to 60 Hz generator. Refer to paragraph 844
for 400 Hz generator removal procedures
a.
Removal.
(1)
Release clamp on generator inlet air cover. Remove inlet air hose and clamp on inlet air cover.
(2)
Release generator terminal cover from generator terminal board. Tag and disconnect generator electrical
connections to generator terminal board. Tag and disconnect wiring harness connector from generator.
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