RQ-C-4824 (ESS Electrical Distribution) Flashcards
The Engineered Safety Electrical System is designed to ensure power is available to:
a. … all plant equipment during normal and abnormal events.
b. … all plant equipment during emergencies.
c. … all safety equipment during design basis accidents.
d. … all safety equipment during non-analyzed accidents.
c. … all safety equipment during design basis accidents.
Which one of the following conditions must be satisfied to enable BOTH automatic and manual closure of the EDG output breaker?
a. EP Breaker must be OPEN.
b. T Bus voltage must be at 0.
c. RCP Bus Tie breaker must be OPEN.
d. DG Run Relay must be energized.
a. EP Breaker must be OPEN.
Unit 1 is at 100% power when an AEO performing the weekly breaker alignment surveillance inadvertently bumps opens breaker 1-MCAB-12 labeled “7.5 KVA Static Inverter Channel IV” on 250 VDC distribution panel “MCAB”. The AEO realizes their mistake and immediately recloses the breaker.
Which ONE of the following describes the effect of these actions?
A) The alternate power source to the CRID Inverter will be lost when the breaker is reclosed. The CRID will transfer to the 120 VAC from the Regulating Transformer.
B) The alternate power source to the CRID Inverter will be lost. No automatic action will occur when the breaker is reclosed. The auto transfer lockout must be reset at the inverter.
C) The normal power source to the CRID Inverter will be lost so it will auto transfer to the alternate source. When the breaker is reclosed, it will auto transfer to the normal source.
D) The normal power source to the CRID Inverter will be lost so it will auto transfer to the alternate source. When the breaker is reclosed, manual transfer will be required.
C) The normal power source to the CRID Inverter will be lost so it will auto transfer to the alternate source. When the breaker is reclosed, it will auto transfer to the normal source.
Which ONE of the following describes a condition that would cause a load conservation signal to be generated for the DG2CD?
a. … Train B SI with a LOOP.
b. … Train B SI and Train B CTS.
c. … Train A SI and Train B CTS.
d. … Train A SI with a LOOP.
d. … Train A SI with a LOOP.
Unit 1 is at 100% power. One of the 4 KV Bus “Loss of Voltage” undervoltage relays on Bus T11A fails to the tripped condition.
Which one of the following describes the effect of this malfunction on the plant?
A) The Loss of Voltage Relays are arranged in a 2 of 3 coincidence, so this failure places the logic in a 1 of 2 coincidence. No actuation occurs.
B) A Load Shed signal for Bus T11A only is initiated, loads are tripped off the T11A bus, the AB Diesel starts, and the Bus T11A loads are sequenced on to the diesel using the Black Out Sequence.
C) A Load Shed signal for Buses T11A and T11B is initiated, loads are tripped off both T11A and T11B, the AB Diesel starts, and the Bus T11A and T11B loads are sequenced on to the diesel using the Black Out Sequence.
D) A Load Shed signal for Bus T11A only is initiated after 2 minutes, loads are tripped off the T11A bus, the AB Diesel starts, and the Bus T11A loads are sequenced on to the diesel using the Black Out Sequence.
A) The Loss of Voltage Relays are arranged in a 2 of 3 coincidence, so this failure places the logic in a 1 of 2 coincidence. No actuation occurs.
