ARMY TM 9-6115-464-34
AIR FORCE TO 35C2-3-445-2
NAVY NAVFAC P-8-624-34
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
Clean all electrical parts with filtered compressed air and a soft bristle brush. If necessary, caked
deposits may be removed with a clean, lint-free cloth moistened with solvent P-D-680 Type Il. Do
not dip electrical parts in cleaning solvent.
Clean non-electrical parts with a clean, lint–free cloth moistened with dry cleaning solvent
(P-D-680) and dry thoroughly.
Visually inspect switch for cracked casing, corrosion, and burns or other evidence of shorting. Check
switch continuity.
Inspect circuit breaker for cracked casing, corrosion, and burns or other evidence of shorting. Check
circuit breaker continuity using an ohmmeter. Replace circuit breaker if defective.
Inspect fuse holder for cracks, corrosion, stripped threads and burns or other evidence of shorting.
Replace if defects are noted.
Inspect indicator light for cracked or broken lens, damaged or defective lamp, cracks, corrosion, and
burns. Replace any defective parts.
Inspect power relay for cracks, corrosion, and burns or other evidence of shorting. Using an
ohmmeter, check power relay coil resistance. Resistance shall be 30-45 ohms at 77°F (25°C).
Replace power relay if damaged or defective.
Inspect transformer for corrosion, cracks, and burns or other evidence of overheating.
Using figure 5-8 as a guide, test transformer as follows:
(a) Using an ohmmeter, check resistance of windings. Winding 1-2 shall indicate 6.77 ± 0.677 ohms.
Winding 3–5 shall indicate 0.108 ± 0.0108 ohm.
(b) Apply 230 Vac, RMS to winding 1-2 with all secondaries open circuit. Exciting current shall be less
than 0.04 amp RMS (0.01 amp RMS for 400 Hz).
(c) Apply 253 Vac RMS to winding 1-2 with all secondaries open circuit. Exciting current shall be less
than 0.065 amp RMS (0.016 amp for 400 Hz).
(d) Apply 230 Vac RMS to winding 1-2 with all secondaries open circuit. Voltage across winding 3-4
shall be 14.8 ± 0.148 volts RMS. Voltage across winding 3-5 shall be 29.6+ 0.296 volts RMS.
(e) Replace transformer if damaged or defective.
(10) Use a semiconductor test set to check semiconductors for inverse current leakage at peak recurrent
inverse voltage of 600 volts. Leakage shall not exceed 20.0 milliamperes at 77°’F (25°C). Check
forward voltage drop. Voltage drop shall not exceed 1.2 volts at 77° F (25° C). Replace defective
semiconductors.
(11) Inspect heat sink and bracket for cracks, corrosion and evidence of overheating.
(12) Inspect wiring harness for loose or damaged connector pins, damaged terminals, worn or chaffed
insulation, and burned areas indicating shorting. Check individual wires for continuity using figure
5-9 as a guide.
(13) If the wiring harness has sustained damage and requires repair or rebuild refer to figure 5-9 for
layout, identification of material requirements and Appendix A references or detailed soldering and
replacement procedures.
(14) Inspect chassis and cover for cracks, corrosion, warping and other damage. Replace parts damaged
beyond repair.
(15) Inspect hardware for crossed, stripped, and peened threads.
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