TM 9-6115-669-13&P
Case 2: EPP III connected by commercial power converter; commercial power converter
providing power to loads changeover to generator 1 or 2.
The changeover is performed as follows:
1.
2.
3.
4.
5.
6.
Generator 1 (or 2) is operating at idle.
Commercial power converter is activated through relay K15, and providing power to the loads.
Changeover is initiated by pressing PARALLEL OPERATION ON pushbutton switch S9 on
the control panel of generator 1 or 2 (refer to TM 9-6115-663-13). The generator checks
synchronization with the commercial power converter in the same way as the PDU electronics
group N6 of the EPP III, measuring voltages by the EPP III bus bars. When synchronization is
achieved, the generator is switched onto the bus bars.
Once generator 1 or 2 is on line, +24 VDC voltage is switched to time relay K14 by diode
A1/V18 or A1/V19. 0.5 seconds after energization of the relay, its contact 15/16 is opened for a
further 0.5 seconds causing relay K15 to de-energize.
Contact 1/2 of K15 opens, and disconnects the commercial power converter from the bus bars
by de-energization of power contactor K40 in the commercial power converter.
PARALLEL OPERATION lamp H9 on the EPP III control panel goes out. Changeover is now
complete.
Case 3: EPP III connected by commercial power converter; EPP III providing power to
loads; commercial power converter shut down.
Circuit conditions are as follows (figure 1-6):
1.
Generator is delivering voltage; K1 activated.
2.
Loads are being powered by PDU; K3, K4, K5, and K6 activated.
3.
K3.1, K4.1, K5.1, and K6.1 in commercial power converter are activated.
4.
ECS is controlling EPP III and receiving signals.
Case 4: EPP III connected by commercial power converter; commercial power converter
providing power to loads; EPP III shut down.
Circuit conditions are as follows (figure 1-6):
1.
ECS is controlling commercial power converter with ECS ON (K10.1), RS ON (K11.1), and
EMERGENCY (K9.1), with same functions at relays K10, K11, and K9 in EPP III.
2.
K40 on, delivering voltage.
3.
Power being provided by K3.1, K4.1, K5.1, and K6.1.
Case 5: Commercial power converter providing power to loads; EPP III not connected.
Same as Case 4, with interlock loops bridged at input J1 to J4 of commercial power converter.
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