SI, SDC (Safety Injection, SDC) Flashcards
Is the Shutdown Cooling Warmup line flow ____ read by the LPSI loop flow transmitters and ____ delivered to the RCS?
A. Is, is
B. Is, is not
C. Is not, is
D. Is not, Is not
B. Is, is not
A loss of coolant accident (LOCA) has occurred.
Several seconds after the trip, a lockout of PBA-S03 occurs.
RCS pressure is currently 250 psia.
If RCS pressure drops to 135 psia, the expected safety injection flow would be increasing HPSI…
A. Flow to all loops and increasing LPSI flow to ONLY loops 2A and 2B cold legs.
B. And LPSI flow to all RCP loops.
C. Flow to all loops and no LPSI flow.
D. And LPSI flow to ONLY reactor coolant loops 2A and 2B cold legs.
A. Flow to all loops and increasing LPSI flow to ONLY loops 2A and 2B cold legs.
Which one of the following is true concerning the 1A safety injection tank?
The safety injection tank can inject water into?
A. Loop’s 1A and 2A.
B. Loop’s 1A and 1B.
C. Loop 1A only.
D. Loop’s 1A, 1B, 2A and 2B.
C. Loop 1A only.
SIAS/CIAS has initiated and RCS pressure is currently 400 psia. RWT Level Channel A reads 10.4%. RWT Level Channel B reads 9.1%. RWT Level Channel C reads 10.0%. RWT Level Channel D reads 9.2%.
A. Both trains of LPSI pumps are running.
B. Both trains of LPSI pumps have tripped.
C. Both trains of HPSI pumps have tripped.
D. Train A LPSI pump is running and the Train B HPSI pump has tripped.
B. Both trains of LPSI pumps have tripped.
Unit 3 has tripped due to low Pressurizer pressure.
The CRS has entered the LOCA EOP. All safety systems have actuated per design.
RWT level is currently 6.8%.
Which ONE of the following indications would NOT be used to determine the presence of RAS sump blockage?
A. HPSI pump amps.
B. LPSI injection flow.
C. CS pump discharge pressure.
D. Containment wide range level indication.
B. LPSI injection flow.
Following a large break LOCA, Standard Appendix 100, Hot Leg Injection, is implemented in order to ____ and should NOT be initiated until a MINIMUM of ____ have elapsed since the start of the LOCA.
A. 1. Minimize the potential for boron precipitation which could restrict flow through the core 2. 2 Hours
B. 1. Minimize the potential for boron precipitation which could restrict flow through the core 2. 3 Hours
C. 1. Ensure sufficient boron exists in the core to prevent core restarts as RCS temp lowers 2. 2 Hours
D. 1. Ensure sufficient boron exists in the core to prevent core restart as RCS temp lowers 2. 3 hours
A. 1. Minimize the potential for boron precipitation which could restrict flow through the core 2. 2 hours
Given the following conditions:
Unit 3 tripped from 100% power due to a large break LOCA.
On the trip, PBA-S03 de-energized due to a fault on the bus.
Based on the listed conditions, Containment pressure should not exceed the Containment design pressure of ____ psig, and should be reduced to 50% of the peak pressure within a maximum of ____ hours of the LOCA initiation.
A. 1. 55 2. 24
B. 1. 55 2. 48
C. 1. 60 2. 24
D. 1. 60 2. 48
C. 1. 60 2. 24
According to the ECCS design criteria found in 10CFR ‘The calculated total oxidation of the cladding shall nowhere exceed ____ of the total cladding thickness before oxidation.’
A. 1%
B. 35%
C. 17%
D. 27%
C. 17%
The HPSI cold leg injection orifice is used during simultaneous hot and cold injection to:
A. Help balance SI flow to the hot and cold leg injection headers by being sized to allow approximately 50% flow.
B. Provide minimum recirculation flow for the HPSI pumps to prevent overheating.
C. Prevent exceeding runout condition in the HPSI pumps to prevent pump cavitation.
D. Provide instrumentation to measure flow to the hot and cold leg injection headers.
A. Help balance SI flow to the hot and cold leg injection headers by being sized to allow approximately 50% flow.
Which one of the following is an important reason to locate and stop a leak in the safety injection piping outside of containment during a large LOCA?
A. Prevent safety injection pump runout during the injection phase following a LOCA.
B. Reduces the amount of fixed contamination that will remain in the containment after repair of the leak.
C. A LOCA outside of containment could result in inadequate containment sump inventory to allow recirculating.
D. Prevent short circuit of the auxiliary building electrical systems with resultant possibility of electric shock.
C. A LOCA outside of containment could result in inadequate containment sump inventory to allow recirculating.
A LOCA has occurred on UNIT 1.
Approximately one minute after the Train B Essential Chiller started, a fault locks out PBB-S04.
RCS pressure is 750 psig and lowering. Based on this, expected safety injection would be:
A. Increasing LPSI and HPSI flow into all reactor coolant loops.
B. Increasing HPSI flow into reactor coolant loops 1A and 1B only.
C. Increasing LPSI and HPSI flow into reactor coolant loops 1A and 1B only.
D. Increasing HPSI flow into all reactor coolant loops.
D. Increasing HPSI flow into all reactor coolant loops.
When filling a safety injection tank (NOP/NOT), which of the following is one possible consequence of stopping the HPSI pump and not closing the SIT fill/drain valve?
A. The SIT will flow into the RWT.
B. The SIT will flow into the RCS.
C. The RWT will flow into the SIT.
D. The RCS will flow into the SIT.
A. The SIT will flow into the RWT.
Reactor Tripped SIAS CIAS MSIS.
All equipment is operating as required.
The Operator places the control switch for SIB-P02 (HPSI Pump) into the START position and then the STOP position.
What effect, if any, will this manipulation have on further pump operation?
HPSI pump ‘B’ has been placed into SIAS override…
A. But will continue to run, unless taken to stop a second time.
B. And stopped, all further starts and stops will have to be done manually.
C. And stopped, it will now respond to any automatic actuation signals.
D. And stopped, it can only be restarted after the SIAS has been reset.
B. And stopped, all further starts and stops will have to be done manually.
A large break LOCA has occurred All systems and components have operated as designed RWT level is 8% on all four channels?
What is currently the suction source of the High Pressure Safety Injection Pumps?
A. Spent Fuel Pool
B. Containment Sump
C. Refueling Water Tank
D. Volume Control Tank
B. Containment Sump
The minimum required volume of the RWT is based on ensuring that by the time of RAS, the water level in the containment sump will be enough to provide NPSH for the ESF pumps and the decay heat boil-off rate is less than…
A. 75% of the minimum design flow of one HPSI pump.
B. 75% of the minimum design flow of two HPSI pumps.
C. The minimum design flow of two HPSI pumps and two LPSI pumps.
D. The minimum design flow of one HPSI pump and one LPSI pump.
A. 75% of the minimum design flow of one HPSI pump.
A large break LOCA has occurred on Unit 2.
Containment pressure is presently 13 psig.
RWT level has dropped to approximately 6%.
Which one of the following would you expect to occur based on this?
A. Both HPSI pumps trip.
B. Containment spray valves close.
C. All safety injection pump recirculation valves close.
D. Safety injection suction valves from the RWT close.
C. All safety injection pump recirculation valves close.
Shutdown cooling is used to cool the Reactor Coolant System from a maximum of ____ to the temperature required for refueling.
A. 500 F
B. 250 F
C. 410 F
D. 350 F
D. 350 F
Which one of the following is true concerning the 1A safety injection tank?
The safety injection tank can inject water into:
A. Loop’s 1A and 2A
B. Loop’s 1A and 1B
C. Loop’s 1A, 1B, 2A, and 2B
D. Loop 1A only
D. Loop 1 A only
Which one of the following is NOT design criteria for Containment Spray?
A. To reduce containment pressure
B. To remove Iodine from the containment atmosphere
C. To minimize the containment sump oxygen levels
D. Operate for a period of one year following a pipe break
C. To minimize the containment sump oxygen levels
The reactor has tripped following a LOCA.
RCS pressure - 430 psia.
RCS temperature - 360 F.
Containment Pressure - 10 psig.
SIAS/CIAS/MSIS/CSAS have initiated.
The primary operator is attempting to align shutdown cooling to the ‘A’ train.
SIC-UV-653, RC Loop 1 to S/D CLG - LPSI PMP ‘A’ suction valve, did not open.
Which one of the following current conditions prevents opening this valve?
A. SIAS signal is present
B. RCS Pressure >385 psia
C. RCS Temperature >350 F
D. Containment Pressure >8.5 psig
B. RCS Pressure >385 psia
Reactor power is steady at 99% Safety Injection Tank (SIT) ‘1B’ indicates the following:
1. Level is 80% narrow range (NR)
2. Boric Acid concentration is 2400 PPM.
3. Nitrogen cover pressure is 620 psig.
4. SIT Outlet valve is open and de-energized.
Which ONE of the following SIT ‘1B’ parameters must be corrected prior to declaring SIT ‘1B’ operable?
A. SIT level must be <72% NR
B. SIT outlet valve must be energized
C. Boric acid concentration must be >4000 ppm
D. SIT nitrogen pressure must be >625 psig
A. SIT level must be <72% NR
Following a large break LOCA, Standard Appendix 100, Hot Leg Injection, is implemented in order to ____ and should NOT be initiated until a MINIMUM of ____ have elapsed since the start of the LOCA.
A. 1. Minimize the potential for boron precipitation which could restrict flow through the core 2. 2 hours
B. 1. Minimize the potential for boron precipitation which could restrict flow through the core 2. 3 hours
C. 1. Ensure sufficient boron exists in the core to prevent core restart as RCS temperature lowers 2. 2 hours
D. 1. Ensure sufficient boron exists in the core to prevent core restart as RCS temperature lowers 2. 3 hours
A. 1. Minimize the potential for boron precipitation which could restrict flow through the core 2. 2 hours
Unit 1 is in Mode 6. LPSI Pump ‘A’ is in service providing Shutdown Cooling flow at 4200 gpm. Subsequently: The 4160 vac class bus (PBA-S03) de-energizes when a fault occurs on the ESF transformer NBN-X03. 1 minute after the fault, shutdown Cooling (SDC) flow is...
A. 0 gpm, LPSI pump ‘A’ breaker is anti-pumped.
B. 0 gpm, LPSI pump ‘A’ is available but did not receive a start signal.
C. 4200 gpm after the ‘A’ DG started and sequenced the LPSI pump on.
D. 4200 gpm, after the Operator throttles the SDC injection valves back to their original position.
B. 0 gpm, LPSI pump ‘A’ is available but did not receiver a start signal.
(Note: DG output breaker will close and energize the bus but there is no ESFAS signal present to close the A LPSI pump breaker)
Unit 3 tripped from 100% power due to a large break LOCA.
On the trip, PBA-S03 de-energized due to a fault on the bus.
Based on the listed conditions, Containment pressure should not exceed the Containment design pressure of ____ psig, and should be reduced to 50% of the peak pressure with a maximum of ____ hours of the LOCA initiation.
A. 1. 55
2. 24
B. 1. 55
2. 48
C. 1. 60
2. 24
D. 1. 60
2. 48
C. 1. 60
2. 24
