ARMY TM 9-6115-643-24
AIR FORCE TO 35C2-3-445-22
2.54. OVER/UNDER VOLTAGE RELAY.
2.54.1.
Inspection.
a. Shut down generator set.
b. Inspect relay for cracked casing, burned or broken terminals, and other damage.
2.54.2. Testing.
a. Shut down generator set.
b. Open battery access door and disconnect negative battery cable.
c. Release control panel by turning two fasteners and lower control panel slowly.
The following procedure disables voltage regulator and allows genera-
tor to reach an overvoltage condition. Do not allow generator set to op-
erate for an extended period of time in an extreme overvoltage condi-
tion.
d. Disconnect wire 137A from AC voltage regulator, terminal 5, and insulate wire end.
e. Connect negative battery cable.
f. Start generator set. As generator accelerates to rated speed, it should instantly shutdown and the OVERVOLTAGE
lamp on malfunction indicator panel should light. If this does not occur immediately shut down generator set.
g. Reconnect wire 137A and disconnect wire 141A from AC voltage regulator, terminal 1. Insulate wire end.
h. Start generator set. As generator accelerates to rated speed, the UNDER VOLTAGE lamp on malfunction indicator
should light. Move AC CIRCUIT INTERRUPTER switch to CLOSED position. AC circuit interrupter relay should
not close.
i. Shut down generator set.
j. Replace over/under voltage relay if generator set does not operate as above.
k. If no repair is needed, reconnect wire 141A at AC voltage regulator.
1. Raise and secure control panel
2.54.3.
Removal.
a. Shut down generator set.
b. Open battery access door and disconnect negative battery cable
c. Remove control box top panel, paragraph 2.15.1.
d. Tag and disconnect over/under voltage relay (45, FIGURE 2-14) electrical leads.
e. Remove screws (44) and over/under voltage relay (45).
2.54.4.
Installation.
a. Install over/under voltage relay (45, FIGURE 2-14) with screws (44).
b. Connect electrical leads and remove tags.
c. Install control box top panel, paragraph 2.15.4.
d. Connect negative battery cable. Close battery access door.
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