SEPS Flashcards
SEPS
DESCRIBE the basic function and design of the Supplemental Emergency Power System – SEPS
• To supply power to one 4.16 kV bus EDE-SWG-5 or EDE-SWG-6 in the event of a loss-of-offsite power (LOOP) and both Emergency Diesel Generators fail to start and load. • In addition the SEPS system will provide backup power to the emergency busses when a EDG is out of service for maintenance for up to 14 days during power operations.
STATE the preferred bus alignment for the Supplemental Emergency Power System
• Bus 6
IDENTIFY the locations where the Supplemental Emergency Power System can be manually started
CP-2 Remote Monitoring & Control Panel
CP-3 Transfer Switch
CP-4 Digital Master Control Panel
CP-5 GenSet 2A
CP-6 GenSet 2B
SUMMARIZE the auto start signal for the SEPS
• The SEPS will auto start when the Digital Master Control Panel, CP-4 receives a loss of power signal after a time delay of < 30 seconds. This signal is sensed at the power supply for the DG Auxiliaries which are fed from MCC 152 input to CP-3 (J3F) AND • Loss of power as sensed on US-63 for < 30 seconds to CP-2 the Remote Monitoring and Control Panel
DESCRIBE the load capability of the SEPS
2700kW each and 2640 kW net
DESCRIBE the function of the major components in the SEPS starting system
Each SEPS has three solenoid energized electric motor starter. The starting motors get their power from their SEPS battery system. Starting batteries are maintenance free and able to operate the starter through five complete series of cranking attempts of at least 15-seconds each, in a five-minute period. (MF batteries installed in 2009 after failure-AR00197779) A fail to start signal is initiated if the engine has not started and further start attempts are blocked until the fail to start signal is been reset
DESCRIBE the function of the major components in the SEPS cooling system
The units are water-cooled and each is supplied with an integral skid mounted radiator and closed loop cooling water system, including jacket water heaters. The radiator cooling fans SEPS-FN-216A and SEPS-FN-216B are driven by electric motors. The fans provide forced air cooling for the enclosure.
DESCRIBE the function of the major components in the SEPS fuel oil system.
System comprised of an integrated positive head fuel oil system which includes: • Storage tank • Engine driven fuel pump • Fuel filters • Cooler • Interconnecting fuel lines
DESCRIBE the function and operation of the SEPS CP-1 transfer switches
Allows for SEPS to be aligned to either bus 5 or 6.
DESCRIBE the function and operation of the SEPS load banks
A resistive and reactive electric load bank is permanently installed and connected to the SEPS system for monthly/Annual load tests. The load bank is sized for 50% of the total generator capacity. Or 100% of one generator’s rating
DESCRIBE the operation of the SEPS Generator Output breakers
• both generators get start signals simultaneously • the 52-G1 or 52-G2 breaker will close on the first generator to reach 90% of rated voltage • the remaining breaker will then synch and breaker will close
STATE the basis for maintaining the SEPS CP-3 Inhibit Switch in Manual
The Auxiliary Power Transfer Switch, 1‑SEPS‑CP‑3 must be in the INHIBIT Mode to prevent the retransfer back to the normal power source upon the return of offsite power to MCC‑152. If SEPS was carrying the Emergency bus and the retransfer was not INHIBITED, then the E-bus that the SEPS was carrying would be lost
DESCRIBE the function and operation of the SEPS Emergency Stop Pushbutton
In the event where entry into the enclosure is deemed hazardous an Emergency Shutdown pushbutton on the north side of GenSets can be used or… If inside the red Shutdown Pushbutton on the PCC3200 can be used
DESCRIBE the necessary steps to locally start SEPS
Turn switch to manual and press the manual start button on CP-5 or CP-6
DRAW and LABEL a simplified diagram of the SEPS distribution system showing power sources, transformers, and interconnecting breakers (including required breaker positions while SEPS is in a standby condition).
