Load Transfer Procedures (Sets connected for parallel operation)

TM 9-6115-663-13&P

On operating generator set (generator 1), set UNIT-PARALLEL switch (16, figure 2-9) to

PARALLEL.

Start generator set 2. Adjust voltage and frequency to match generator set 1.

At switch box, set generator set 2 ON-OFF switch (3 or 6) to ON (Switch box STATUS and ON

LINE lights for both generator sets should be lit).

At generator set 2 control panel:

(1) Set UNIT-PARALLEL Switch (16) to PARALLEL. Both SYNCHRONIZING LIGHTS (12))

should be going bright to dark together.

CAUTION

If synchronizing lights on generator set 2 do not go bright and dark in

unison, the phasing is wrong. Shut down generator sets and check that

load cables are connected properly. Failure to observe this caution can

result in damage to generator sets.

( 2 Increase frequency until SYNCHRONIZING LIGHTS (12) blink together one or more times per

second.

(3) Decrease frequency until SYNCHRONIZING LIGHTS (12) blink together once every 3-4

seconds.

(4) While both synchronizing lights are dark, position and hold AC CIRCUIT INTERRUPTER

switch of generator set 2 in- the CLOSED position until indicator lights. SYNCHRONIZING

LIGHTS should go out (both generators are now operating in parallel).

Once both of the generator sets are on line and supplying power to the load in parallel, perform

the following steps to transfer the load.

(1) At the control panel of the generator set that is to be taken off line (generator set 1), set the

AC CIRCUIT INTERRUPTER switch to the OPEN position. Set UNIT-PARALLEL switch to

UNIT, MASTER SWITCH to OFF.

(2) At the control panel of the running generator set (generator set 2), place the UNIT-PARALLEL

switch to UNIT. The load has now been transferred.

Perform the generator PMCS listed as DURING for generator set 2 and AFTER for generator set

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