Feedwater Flashcards
“A” shell main condenser vacuum breaker has failed Open Rx has tripped on low SG levels AFA-P01 has failed due to a loss of lubricating oil. AFN-P01 has a brighter than normal green light, confirmed 86 lockout and a ground fault trip. PKB-M42 is de-energized due to a fault. Which one of the following should be pursued as the primary method of restoring feedwater?
A. Restart a Main Feed Pump.
B. Local operation of AFA-P01.
C. Local operation of AFN-P01.
D. Local operation of AFB-P01.
Answer: D
A steam generator should be “bottled up” if it is expected to take longer than _________ minutes to recover feedwater.
A. 30
B. 15
C. 45
D. 60
Answer: B
Which one of the following is the power level we normally place the second main feedwater pump in service?
A. 65-75%
B. 20-30%
C. 35-45%
D. 50-60%
Answer: D
Plant is at 100% power. Which one of the following describes the response of the main feedwater pump mini-flow valves to a complete loss of instrument air? The valves…
A. fail closed.
B. fail as is.
C. fail open.
D. remain closed due to hydraulic accumulator backup.
Answer: C
100% power. NBN-S01 deenergized due to a fault. Feed pump suction pressure decreased to 200 psig and remains at 200 psig throughout the transient. With NO operator actions, which one of the following is true?
A. After a 10 second time delay the B MFWP trips, RPCB initiates and the plant stabilizes at approximately 60%.
B. The A and B MFWPs immediately tripped as suction pressure decreased to less than 255 psig.
C. After a 10 second time delay the A MFWP trips, RPCB initiates and 5 seconds later the B MFWP trips.
D. After a 10 second time delay the B MFWP trips, RPCB initiates and 5 seconds later the A MFWP trips.
Answer: D
Which one of the following conditions would cause a Main Feedwater Pump Turbine trip?
A. FWPT suction pressure at 255 psig for 10 seconds.
B. FWPT high eccentricity at 2 mils.
C. FWPT vacuum is 14.5 inches HgA.
D. FWPT inactive thrust bearing wear oil pressure at 35 psig.
Answer: C
Main Feed Pump A has a longer time delay associated with its low suction pressure trip than Main Feed Pump B. Why is this true?
A. Differences in time delays ensure both MFPs will trip when required.
B. Differences in the time delays prevents tripping both pumps on short transient.
C. Prevents a serious water hammer event by staggering major system perturbations.
D. Prevents damage to heater drain pump seals due to rapid rise in Condensate presure caused by simultaneous MFP trips.
Answer: B
Four conditions that will cause a Feedwater Pump Trip are:
A. Low suction pressure, thrust bearing wear, overspeed and high condenser back pressure.
B. Thrust bearing wear, overspeed, low condenser back pressure, and low lube oil flow.
C. Low suction pressure, MSIS actuation, high exhaust vacuum and loss of seal water.
D. High suction pressure, thrust bearing wear, low feedwater pump flow and high exhaust vacuum.
Answer: A
Reactor is tripped. Condenser air in leakage through a damaged seal has caused condenser vacuum to degrade to 9.5” HgA and stabilize there. Based on these conditions Main Feedwater is currently..
A. available with ADV’s only.
B. unavailable, AFW must be used with ADV’s only.
C. unavailable, AFW must be used with ADV’s or SBCS.
D. available with SBCS or ADVs.
Answer: D
Which of the following will cause a Main Feedwater Pump Turbine trip?
A. Suction pressure of 225 psig for 8 seconds.
B. Discharge pressure of 1700 psig.
C. Speed of 6000 rpm.
D. Main Condenser vacuum of 15 inches HgA.
Answer: D
Which ONE of the following statements is true regarding the MFWP mini-flow control valve?
A. Fails closed on Loss of Electrical Power.
B. Fails as is on Loss of Instrument Air.
C. Closes on MFPT Trip.
D. Remains full open until total feedflow is > 7000 gpm.
Answer: C
Reactor power is at 25% and DFWCS is in automatic. A feedwater temperature transmitter fails low. Which of the following represents the canned value that will be used by DFWCS?
A. 350 deg F
B. 0 deg F
C. 425 deg F
D. 500 deg F
Answer: C
Which of the following inputs to the Digital Feedwater Control System is used for indication only?
A. Tavg
B. Downcomer flow transmitters
C. Turbine Load Index
D. Steam Bypass Master Controller output
Answer: B
Unit 1 is at 100% power All control input transmitters to the Digital Feedwater Control system (DFWCS) are in service and selected to AVERAGE(where applicable). One feedwater flow transmitter fails low. Which one of the following describes the operator action for this DFWCS input failure?
A. No action required because the DFWCS will automatically choose the higher flow at 4% flow deviation.
B. Place the lower reading feedwater flow transmitter into maintenance.
C. No action required because the DFWCS will automatically choose the higher flow at 8% flow deviation.
D. Place the higher reading feedwater flow transmitter to maintenance.
Answer: B
WHICH ONE of the following identifies a condition which would result in a trip of a main feedwater pump?
A. Feedwater pump suction pressure of 290 psig.
B. Condenser shell pressure of 11 in HgA.
C. Feedwater pump turbine bearing oil pressure of 3.5 psig.
D. Feedwater pump discharge pressure of 1835 psig.
Answer: C
