5. Start the incoming set. The on-line set should be in operation already.
6. After a 5-minute warmup, try the VOLTAGE ADJUST control on the incoming set until the output voltages of both sets are equal.
If the synchronizing lights do not blink on and off in unison, the phase sequence is incorrect. Shut down the incoming set and recheck the cabling to and from the incoming set.
7. On the incoming set, position the ENGINE MANUAL SPEED CONTROL until the SYNCHRONIZING LIGHTS blink on and off as slowly as possible.
8. With one hand on the CKT BRK switch, adjust the ENGINE MANUAL SPEED CONTROL vernier knob until the SYNCHRONIZING LIGHTS dim gradually from full on to full off as slowly as possible. Just as the SYNCHRONIZING LIGHTS dim to out, set and hold the CKT BRK switch to close. When the CKT BRK indicator light comes on, release the switch.
9. On both sets, check that the readings of the PERCENT RATED CURRENT meters and KILOWATTS meters are well within 20 percent of each other. If not, increase the engine power of the set with the lower readings (by adjusting the ENGINE MANUAL SPEED CONTROL to increase the speed) until the readings are about equal.
NOTE: The division of the kilowatt load is also dependent on the frequency droop of the two sets and must be adjusted at the next higher level of maintenance. If the current does not divide as described above, adjust the reactive current-sharing control located at the right side of the special relay box for equal reading on both percent rated current meters.
10. On the incoming set, readjust the voltage and frequency of the output until it is equal to the output of the on-line set.
Refer to figure 3-19 while following the procedure for removing a generator set from parallel operation. 3-26
Before removing the generator set(s) from parallel operation, make sure the load does not exceed the full-load rating of the generator set(s) remaining on the line.
1. On the outgoing set, position and hold the CKT BRK switch to OPEN until the CKT BRK indicator light goes out. Release the switch.
2. On the outgoing set, allow the engine to operate with no load for about 5 minutes.
3. On the outgoing set, pull the DC CONTROL CIRCUIT BREAKER to OFF.
4. On the outgoing set, set the START-STOP- RUN switch to STOP.
WARNING Make certain the outgoing set is shut down and there are no voltages at the switchgear terminals connected to the outgoing set. Do not take anybodys word for it! Check it out for yourself!
5. Disconnect the cables going from the outgoing set to the load switchgear.
Stopping Generator Set Operation
Refer to figure 3-19 as you study this section.
1. Set the CKT BRK switch to OPEN until the CKT BRK indicator light goes out, then release the CKT BRK switch.
2. Allow the engine to cool down by operating at no load for 5 minutes.
3. Set the START-STOP-RUN switch to STOP.
4. Close all generator doors.
There are actually three major categories (or levels) of maintenance. The three categories are (1) depot, (2) intermediate, and (3) organizational. In depot or intermediate maintenance, equipment is restored to like-new condition or subjected to some degree to detailed repairs. Under the organizational category, generator maintenance may consist of inspection, testing, adjustment, and so forth, and then perhapsContinue Reading