RQ-C-4952, instrument Electrical Distribution Flashcards
Which ONE of the following describes the response of the CRID 2 inverter to a loss of 600 VAC power to the Regulating Transformer?
A) The internal static switch for the inverter automatically selects an alternate AC power source.
B) The battery will supply the CRID 2 inverter, as soon as its DC input breaker automatically closes.
C) The battery will supply the CRID 2 inverter, as soon as an operator closes the DC input breaker.
D) The “In Sync” light on the inverter will be extinguished and the inverter abnormal alarm will annunciate.
D) The “In Sync” light on the inverter will be extinguished and the inverter abnormal alarm will annunciate.
The following conditions exist:
Unit 1 is operating at 25% power.
All electrical systems are in normal alignment.
The normal incoming breaker to Bus EZC-A trips.
Which ONE of the following describes the effect on CRID-3 distribution?
A) No effect; CRID-3 inverter will swap to alternate power from EZC-B.
B) No effect; battery panel MCAB will continue to power CRID-3 inverter.
C) No effect; battery panel MCCD will continue to power CRID-3 inverter.
D) De-energized; CRID-3 distribution must be transferred to CRP-3
B) No effect; battery panel MCAB will continue to power CRID-3 inverter.
An operator incorrectly opens the breaker labeled “7.5 KVA Static Inverter Channel IV” on 250 VDC distribution panel “MCAB”. The operator realizes the 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, the auto transfer lockout must be reset at the inverter.
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, it will auto transfer to the normal source after 30 seconds.
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, it will auto transfer to the normal source after 30 seconds.
Unit 2 is at 100% Power. There is currently a FIP on Unit 2 CRID 2 Inverter due to a failed inverter card. Unit 2 CRID 2 is currently supplied with power from the Alternate Source through the Manual Output Selector Switch.
Unit 2 CRID 3 Inverter then automatically swaps to the Alternate Source and does NOT transfer back to the Normal Source. The reason for the transfer is not known at this point.
What is the most limiting LCO Action?
A) None. The Inverters remain OPERABLE since they are supplying the CRID busses.
B) TS 3.8.7 Condition A applies since the CRID 2 Inverter is Inoperable.
C) TS 3.8.7 Condition B applies since both Inverters are Inoperable.
D) TS 3.0.3 since an associated action is not provided
D) TS 3.0.3 since an associated action is not provided
