INSPECTION - TM-5-4120-393-140156

TM 5-4120-393-14

4-43. Relays (K1, K2, K7, and K8) (cont)

INSPECTION

Check for loose, corroded, missing, or broken terminal connections.

Check relay for cracks, evidence of overheating, and other visible damage and replace if damaged.

TESTING

Use a continuity tester or multimeter set on the lowest OHMS scale to check continuity between terminals A1 and A2,

B1 and B2, and C1 and C2. All three contacts should be opened. If there is continuity, replace relay.

Check continuity between coil terminals X1 and X2. If there is no continuity, the coil is open, replace relay.

Apply 24 volts dc across terminals X1 and X2 and repeat continuity checks between terminals A1 and A2, B1 and B2,

and C1 and C2. All three contacts should be closed. If there is no continuity, replace the relay.

Remove the 24 volts dc from the coil terminals X1 and X2.

INSTALLATION

Using wrench, secure relay (8) with four washers (4) and nuts (3).

See tags and wiring diagram, para 4-13, and connect wire leads.

Remove tags.

Install nut (5), washer (6), and terminal cover (7) to relay (8).

Using screwdriver, install junction box cover (2) with four screws (1).

NOTE

FOLLOW ON MAINTENANCE:

1. Install lower front panel. See para 4-24.

2. Connect power.

4-104