TM 9-6115-604-34
NAVFAC P-8-633-34
(8)
Observe that multimeter reads less than 1 ohm.
(9)
Disconnect 24 V dc power supply.
(10)
Observe that multimeter reads infinite ohms.
(11)
Repeat steps (1) through (10), above, several times to ensure that relay works consistently.
(12)
If multimeter does not produce required reading, relay is defective and must be replaced.
e.
Install. Install relay (38) by plugging into relay socket (39) and securing with screw assembly (40) and
lockwasher (41).
5-29. TIME DELAY (LOW FUEL LEVEL SHUTDOWN) RELAY K23 (49, Figure 5-9). This socket mounted relay is
located in the upper cabinet A panel and is energized by high/low alarm float switch FL3 and low fuel level alarm relay
A10K5. If K23 remains energized for 35 minutes, it will energize the fault shutdown relays K20A and K20B and the
generator set will shut down.
a.
Remove. Remove relay K23 (49, Figure 5-9) by removing screw and captive washer assemblies (51) and
unplugging it from its socket (50).
b.
Inspect.
(1)
Inspect adjustment knob and nylon case for damage.
(2)
Verify adjustment knob is set to mid-range (35 minute) setting.
(3)
Remove in accordance with step a, above. Inspect for bent or broken pins. Check for cracks in phenolic
base.
c.
Off Equipment Test (see Figure 5-27).
(1)
Connect a multimeter (RX1 scale) across relay pins 1 and 3.
(2)
Observe that multimeter reads infinity.
(3)
Connect a 24 V dc power supply across relay pins 2 (positive) and 7 (negative).
(4)
Set adjust knob to desired trip time.
(5)
Observe that multimeter first reads infinite ohms, then less than 1 ohm after the preset time has elapsed.
(6)
Disconnect 24 V dc power supply.
(7)
Observe that multimeter reads infinite ohms.
(8)
If multimeter reading is not as specified for any step, replace the relay.
(9)
Relay K23 should always be adjusted to the mid-range setting. This will produce a delay of 33 to 37
minutes between energizing and contact closure. In step (5), above, elapsed time should be 33 to 37
minutes.
d.
Adjust. Adjust relay K23 by setting the adjust knob to the midrange (35 minute) setting.
e.
Install. Install relay K23 (49, Figure 5-9) by plugging it into its socket (50) and secure with mounting screws (51).
5-30. CIRCUIT BREAKER TRIP RELAY K30 (52, Figure 5-9). This relay is energized whenever the operator sets
BREAKER CONTROL switch S4 to TRIP (and LOCAL REMOTE SWS2 is set to LOCAL) and whenever a fault condition
occurs. If LOCAL REMOTE SW S2 is set to REMOTE, BREAKER CONTROL switch S4R will energize relay K30.
When energized. K30 energizes the trip coil of load circuit breaker CB101, and the circuit breaker trips (opens).
a.
Remove.
(1)
Tag and disconnect wires to relay K30 (52, Figure 5-9).
(2)
Remove screw and captive washer assembly (53) to remove relay K30 (52).
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