ARMY TM 9-6115-670-14&P
4-151
4.59. AC VOLTAGE ADJUST POTENTIOMETER.
This task covers: a. Test b. Replace
INITIAL SETUP
Tools
General Mechanic's Tool Kit
(Item 1, Appendix B)
Shop Equipment, Electrical, Repair,
Semitrailer Mounted
(Item 3, Appendix B)
Multi-meter
Equipment Conditions
APU control unit disconnected from shelter.
Materials/Parts
Ac Voltage Adjust Potentiometer
TEST
a. Disconnect Plug J2 from P2.
b. Connect Multi-meter between terminals 1 and 3. Resistance should be 1000 ohms +/- 50 ohms.
c. Connect Multi-meter between terminals 2 and 3. Turn Potentiometer shaft. Resistance should vary
between 0 and 1000 ohms.
d. Replace Potentiometer if defective.
REPLACE
a. Remove ten screws (caged nuts (SICPS), machine screws (JTACS and WIN-T)) (1, Figure 4-47)
securing APU control unit cover to chassis and remove cover.
b. On potentiometer (5), identify and tag terminal leads (4).
c. Carefully cut away insulation sleeving and expose soldered connections.
d. Unsolder terminal leads (4).
e. Loosen two hex-head screws (2) and remove potentiometer knob (6).
NOTE
Display plate on JTACS and WIN-T only. JTACS and
WIN-T unsolder, SICPS remove shrink wrap and
unsolder.
