TM 11-6125-220-20
3-6. Cleaning
Avoid prolonged skin contact with trichloroe-
thane.
All exterior surfaces of the inverter should be free of dirt,
grease, and fungus. Perform the following procedures
b. Remove grease, fungus, and ground-in dirt from
as specified in the preventive maintenance checks and
the exterior surfaces with a clean cloth dampened (not
services table 3-1.
wet) with trichloroethane. Wipe dry with a clean, dry,
lint-free cloth.
a. Remove moisture and loose dirt with a clean soft
cloth.
c. Remove dust or dirt from ac power connector and
associated plug with a soft-bristle brush.
WARNING
The fumes of trichloroethane are toxic. Pro-
3-7.
Troubleshooting
vide thorough ventilation whenever used. DO
The troubleshooting procedures in table 3-3 are based
NOT USE NEAR AN OPEN FLAME. Tri-
upon symptoms noted while the inverter is in operation.
chloroethane is not flammable, but exposure
Any malfunction observed that is not included in the
of the fumes to an open flame or hot metal
table should be referred to higher category maintenance.
surface forms highly toxic phosgene gas.
Troubleshooting
Table 3-3.
Malfunction
Possible cause
Corrective action
Inverter vibrates . . . . . . . . . . . . . . . . . . .
a.
a. Tighten or replace hardware.
Loose or missing hardware.
b.
b. See that mounting surface is clean and free of
Inverter improperly seated.
foreign objects. If trouble is not corrected
higher category maintenance is required.
Inverter fails to start . . . . . . . . . . . . . . .
a.
a. Check and replace or reset as required.
Loose or blown fuses or
open circuit breaker in dc line.
b. Check aircraft line fuses or circuit
b.
Short circuit in dc line...
breakers. If blown, inspect wiring between
fuses or circuit breakers and inverter.
Repair wiring as necessary.
c.
Dc brushes not making
c.
Refer inverter to higher category maintenance.
contact with commutator.
d.
Dc input circuit open . . . . . . . . . . . . . . . . .
d. Check wiring and connection to the inverter
for an open circuit. Repair or replace as
necessary.
e. Refer inverter to higher category
Armature jammed . . . . . . . . . . . . . . . . . . .
e.
maintenance.
a. Connect an AN/UPM-93 to the test point
a.
Inverter runs but fails to deliver
Ac circuit open.
jacks on the front of the regulator
proper voltage or frequency
If indication is between 109 and 121 vac,
390 and 410 Hz, check exterior wiring and
connections for an open circuit, and repair. If
indication is not specified, refer
inverter to higher category maintenance.
b. Remove ac electrical end caps and check
b.
Slipring brushes not making
for broken brushes or springs. Refer
contact with slipring.
inverter to higher category maintenance.
c. Refer inverter to higher category
c.
Regulator failure.
maintenance.
a. Check dc voltage at power supply and correct.
a.
Ac output voltage is low . . . . . . . . . . . .
Dc input voltage is low.
3-3
