2010 NRC RO Exam Flashcards
- Which one of the following describes the response of a Relief/Safety Valve to a rising RPV pressure if a pneumatic supply is NOT available from any source?
A Relief/Safety Valve will …
A. function in its pressure relief mode and in its safety mode.
B. NOT function in its pressure relief mode but will function in its safety mode.
C. function in its pressure relief mode and NOT function in its safety mode.
D. NOT function in its pressure relief mode and NOT function in its safety mode.
A: Incorrect: A pneumatic supply (accumulator I continuous) is required to lift in the Pressure Relief mode.
B: Correct: A pneumatic supply is not required in the Safety mode. In the safety mode, whenever reactor pressure is greater than spring pressure the valve will open.
- While at rated conditions, a fire in the Relay Room results in entry into N2-S0P-78, Control Room Evacuation. The following occur:
- All SOP-78 Control Room actions are completed before evacuating the Control Room
- Before any action is taken outside the Control Room, the Automatic Depressurization System (ADS) spuriously initiates and all ADS valves open.
- Shortly thereafter all appendix R disconnect switches on panels 2CES*PNL415, 416 and 417 are placed in the actuate position.
Which one of the following describes the response of the ADS valves?
A. All ADS valves will close when the disconnect switches are placed in actuate.
B. All ADS valves remain open and cannot be closed unless solenoid fuses are removed.
C. The four ADS valves controlled from Remote Shutdown Panel, 2CES*PNL405 close. The remaining three will not close until solenoid fuses are removed.
D. The four ADS valves controlled from Remote Shutdown Panel, 2CES*PNL405 will close when their switches are taken out of the NORMAL position. The remaining three will not close until solenoid fuses are removed.
A: Correct: Per N2-0P-78, Remote Shutdown System Attachment 2, disconnect switches SW1-2CESA02 (Div 1) and SW1-2CESB02 (Div 2) isolate solenoids for the 4 ADS valves controlled from the remotes shutdown panel. Switches SW1-2CESA04 (Div 1) and SW1-2CESB04 (Div 2) isolate remainder of ADS circuitry.
B: Incorrect: Per N2-0P-78, Remote Shutdown System Attachment 2, disconnect switches SW1-2CESA02 (Div 1) and SW1-2CESB02 (Div 2) isolate solenoids for the 4 ADS valves controlled from the remotes shutdown panel. Switches SW1-2CESA04 (Div 1) and SW1-2CESB04 (Div 2) isolate remainder of ADS circuitry.
C & D: Incorrect: When the disconnect switches are repositioned, the ADS solenoids lose power and the valves close. See A & B above.
- Which one of the following power supply failures would result in a loss of the RPS “A” Analog Trip Units on panel 2CEC*PNL609?
Loss of …
A. 2VBB-UPS1A.
B. RPS UPS 2VBB-UPS3A.
C. RPS MG set 2RPM-MG1A.
D. Emergency UPS 2VBA*UPS2A.
B: Correct: RPS UPS 2VBB-UPS3A is the power supply
- The plant is in Mode 4 when 600V distribution panel 2NJS-PNL600 is de-energized.
Assuming no operator actions which one of the following is the affect of this loss on the Source Range Monitors (SRM)?
A. SRM Channels A and C de-energize immediately.
B. SRM Channels A and C de-energize after several hours.
C. SRM Channels Band D de-energize immediately.
D. SRM Channels Band D de-energize after several hours.
D: Correct: 2NJS-PNL600 powers chargers 2BWSCHGR3B1 and 2BWS-CHGR3D1. Although both chargers are lost, the SRMs remain energized via 2BWS-BAT3B/3D. These batteries are sized to maintain voltage for up to 4 hours before voltage begins to decay. If the chargers are not restored, SRMs will eventually de-energize.
- The plant is at rated conditions when a complete loss of Normal 125 VDC Power bus 2BYS-SWG001A occurs.
Which one of the following is a direct plant response to this event?
A. Main turbine immediately trips
B. BOTH Recirc pumps immediately trip
C. Loss of Main Generator protective relays control power
D. Loss of control power to 2NPS-SWG001/2/3 load breakers
C: Correct: The loss of 2BYS-SWG001A causes a loss of Main Generator protective relays control power and results in Annunciator 852604, Generator protective relays control power failure.
- A plant startup in progress with the following:
- Reactor power is 30%
- The Rod Worth Minimizer (RWM) is in the Transition Zone Then, the UPS supply breaker to the RWM trips.
Other than scramming the reactor which one of the following describes the current control rod movement capability?
A. Rods can be withdrawn OR inserted using the reactor manual control system.
B. Rods CANNOT be withdrawn OR inserted using the reactor manual control system.
C. Rods can only be inserted if the Continuous Insert push button is used. Rods CANNOT be withdrawn using any method.
D. Rods can only be inserted if the Continuous Insert push button is used. Rods can only be withdrawn if the Continuous Withdraw mode is used.
B: Correct: Loss of power to RWM removes permissive to move rods.
- The following conditions exist:
- The reactor is in Mode 3.
- RHR Loop “B” has just been placed in Shutdown Cooling
- Reactor pressure has risen to 150 psig
Which one of the following would indicate that a failure had occurred in the automatic response of the RHR system?
A. RHR*P1 B pump is running
B. RHS*MOV2B, PMP 1 B SDC SUCT VLV is open
C. RHS*MOV40B, SDC B RETURN THROTTLE is closed
D. RHS*MOV8B, HEAT EXCHANGER 1B INLET BYPASS VALVE is in mid position (throttled)
A: Correct: The pump should have tripped on loss of suction flowpath when MOV112 and 113 closed.
- The plant is at rated conditions when the following indications are received.
- Annunciator 601706, HPCS System INOP alarms
- Amber System Status Light “HPCS Line Break” illuminates
Which one of the following describes the impact if a Standby Liquid injection is required? If the system is actuated Standby Liquid will inject into the …
A.
core shroud region of the reactor vessel.
B.
downcomer region of the reactor vessel.
C.
drywell and will NOT reach the reactor vessel.
D.
core shroud region but NOT the HPCS spray header.
B: Correct: Alarm annunciates on high pressure when CS injection line pressure rises. This occurs when the CS injection line rises to downcomer pressure when the line breaks outside the shroud but inside the vessel. SLS injection would still be via the downcomer.
- The plant was at rated condition when the following occur:
- A complete loss of off-site power occurred
- Emergency Diesel Generators (EDGs) start and re-power their respective buses.
- Ten minutes later, all Division I 125 VDC is lost.
Which one of the following is the current status of 2EGS*EG1 and its output breaker 101-1?
EGS*EG1 ; BRKR 101-1
A. Tripped ; Open
B. Tripped ; Closed
C. Running ; Open
D. Running ; Closed
B: Correct: Loss of DC control power will de-energize the EDG trip relays tripping the diesel, and breaker 101-1 will not open due to no power to its trip coil.
- A reactor plant startup is being conducted in accordance with N2-0P-101A.
- The reactor is critical and SRM/IRM overlap data has just been completed.
- All SRMs are reading between 5 X 10E4 and 1 X 10E5 cps
- All IRMs are on mid scale on range 1
- The operator has selected both the SRMs and the IRMs for withdraw.
Which one of the following will be the first automatic protective action as the detectors are withdrawn?
A. SRM INOP trip
B. IRM Downscale rod block
C. SRM Downscale rodblock
D. IRM Detector NOT fully inserted rod block
D: Correct: When the withdraw function is selected the first action will be the movement of the SRM and IRM detectors from the core. Immediately the IRMs will be detected to be not fully inserted This rod block is active whenever the mode switch is not in run.
- A plant startup is in progress, with the following:
- Feedwater Pump A is in service
- All three Feedwater Pump Suction MOVs, CNM-MOV84A, B and C, are open
- Low Flow Control Valve 2FWS-LV55A is controlling RPV level in AUTO
- 2FWS-LV55A is currently 40% open
Then, instrument air to ALL Feedwater valves is lost
Which one of the following describes the effect on 2FWS-L V55A position and reactor water level?
2FWS-LV55A Position ; Reactor Water Level
A. Fails closed ; Lowering, below normal level
B. Fails as is ; Constant, normal level
C. Fails as is ; Lowering, below normal level
D. Fails open ; Rising, above normal level
C: Correct: Low Flow Control Valve 2FWS-LV55A fails as is on loss of air. Feed pump min flow valves fail open on loss of air, diverting water from the reactor resulting in a lowering level.
- The plant is at rated conditions when a complete loss of pneumatics to 2CCP-TV108, RB CLOSED LOOP COOLING TEMPERATURE CONTROL VALVE, occurs.
Which one of the following describes the effect of this failure on the CCP heat exchanger?
A. MORE flow is directed to SHELL side of heat exchanger.
B. MORE flow is directed to TUBE side of heat exchanger.
C. LESS flow is directed to SHELL side of heat exchanger.
D. LESS flow is directed to TUBE side of heat exchanger.
A: Correct: On a loss of air, 2CCP-TV1 08 positions itself to provide maximum cooling. The valve in the heat exchanger discharge header will fail open and the valve in the heat exchanger bypass line fails closed, which directs MORE flow through the SHELL side of the heat exchanger.
- Following a small break on a Recirc Loop the following conditions exist:
- Low Pressure Core Spray is the only injection system available
- RPV water level has been restored
- Low Pressure Core Spray Injection Valve, 2CSL *MOV1 04, is throttled and Core Spray Flow is 2000 gpm
Then, the recirc loop under goes a double guillotine shear. In response to the lowering RPV level the operator fully opens 2CSL*MOV104.
Per design, Core Spray injection will:
A. Raise level to the level of the Main Steam Lines
B. Stabilize level at approximately -14 inches (actual level)
C. Stabilize level at approximately -62 inches (actual level)
D. Be insufficient to recover level to above the Bottom Of the Active Fuel
C: Correct: -62 inches is the level of the jet pump suctions. During a design bases accident, one ECCS is expected to re-flood to the top of the Jet pump suctions.
- Following a reactor scram and loss of off-site power, RCIC is manually started to control RPV level. Current conditions are:
- RPV level is 180 inches and slowly rising
- RCIC Flow Controller 2ICS*FC101 is in Auto
- RCIC Flow Controller 2ICS*FC101 setpoint has been reduced to 400 gpm.
In order to control RPV level, ICS*MOV124, Test Bypass to Condensate Storage Tank, is opened and ICS*FV108, Test Bypass to Condensate Storage Tank, is throttled in mid position.
Which one of the following are the responses of RPV injection flowrate and RCIC Flow indication on RCIC Flow Controller 2ICS*FC101, if ICS*FV108 is opened further?
RPV injection flowrate ; RCIC Flow Controller indication
A. Lower ; Remain the same
B. Lower ; Lower
C. Raise ; Remain the same
D. Raise ; Raise
A: Correct: Further opening of the Test Bypass will divert additional flow to the CST. The controller sees the increase in flow and closes down on the turbine, keeping flow at 400 gpm.
- The plant is operating at 100% power with a normal Reactor Building ventilation configuration. Reactor Building differential pressure is -0.6 inches WG when the following sequence of events occur:
1300: Drywell pressure rises to 14 psig
1300: GTS Trains A and B automatically start
1310: GTS Train A is shutdown by placing Train A Initiation control switch in Auto After Stop
1315: GTS Train B Fan trips due to a blown control power fuse
Which one of the following describes the impact of these events on Reactor Building differential pressure (DP) and the actions required, per N2-0P-61 B, to restore RB differential pressure?
Reactor Building DP ; Actions Required
A. Becomes less negative ; GTS Train A must be manually restarted
B. Becomes less negative ; Confirm automatic restart of GTS Train A
C. Becomes more negative ; Defeat high Drywell pressure interlocks and restart HVR
D. Becomes more negative ; Confirm automatic restart of GTS Train A
B: Correct: GTS Train A restarts because the high Drywell pressure (>1.68 psig) initiation signal is still present and with no running GTS train RB differential pressure will degrade toward 0. When pressure reaches -0.25 inches WG, the manually shutdown train will automatically restart.
- Following a loss of coolant accident and loss of off-site power the following conditions exist:
- RHR Loops A and B are injecting
- NO other ECCS injection sources are available
- Reactor pressure is 100 psig and steady
- Reactor level is 50 inches and steady
While in these conditions RHR Pump A trips and cannot be restarted.
Which one of the following describes an Alternate Injection System that N2-EOP-6 Attachment 6 specifies to re-establish level control?
A. Fire water cross tied to RHR Loop B
B. Service Water cross tied to RHR Loop B
C. Fire water cross tied to RHR Loop A
D. Service Water cross tied to RHR Loop A
C: Correct: Attachment 6 provides direction to align firewater provided the loop is currently NOT being utilized. Reactor pressure is also low enough to allow firewater injection.
- With the plant at rated conditions the following occur:
- Drywell pressure rises to 2 psig
- The Standby Diesel generators start and run unloaded.
Two minutes later the following 2EGS*EG1 indications are observed in the control room:
- Engine RPM: 608 RPM
- Generator VARs: 0 VARS
- Generator AC output voltage: 4170 VAC
Given these indications, which one of the following is correct?
A. The Auto Voltage Regulator has failed and the voltage regulator has shifted to manual.
B. The Primary Control Circuit (Control Circuit #1) has failed and the engine is operating in Parallel Mode.
C. The electronic speed control governor has failed and the hydraulic governor is controlling engine speed.
D. A complete failure of the electronic-hydraulic control governor has occurred and engine speed is being controlled by the overspeed governor.
C: Correct: A failure of the electronic speed control governor will shift control to the hydraulic governor which will control the engine at -608 RPM. The frequency indicated is the frequency associated with a 12 pole engine operating at 608 RPM.
- Following a plant transient, High Pressure Core Spray (HPCS) auto initiates and injects. HPCS recovers level and injection flow stops when CSH*MOV107, Pump 1 Injection Valve, closes on RPV high level. Current plant conditions are as follows:
- RPV level is +180 inches and lowering
- Drywell pressure 1.2 psig and rising
- No operator actions have been taken up to this point.
Then Drywell pressure rises above 2 psig.
Given the above, which one of the following is correct regarding the response of CSH*MOV1 07 and the required actions, if ANY, to restore injection at this time?
CSH*MOV107 will… , Required Actions
A. Automatically open, None
B. Remain closed, Depress the Hi WTR Level Seal-In Reset
C. Remain closed, Depress the Manual Initiation Seal-In Reset
D. Remain closed, Place the control switch for CSH*MOV107 to the OPEN position
A: Incorrect: CSH*MOV107 is interlocked closed until level lowers to level 2 or the high water level reset is depressed.
B: Correct: CSH*MOV107 will re-open if high level reset is depressed.
C: Incorrect: The initiation will reset but CSH*MOV107 will not re-open until level lowers to level 2.
D: Incorrect: CSH*MOV107 cannot be opened manually until the high level is reset.
- The reactor is at 100% power when the Key Lock switch on LPRM Chassis 1 is placed in the INOP position.
How will this affect the Input Status lights for APRM 1 on Two-Out-Of-Four Logic Module, MDL 1?
A. All status lights will remain extinguished.
B. The OPRM status light will illuminate. All others will be extinguished.
C. The HIGHIINOP status light AND the OPRM status light will illuminate.
D. The HIGHIINOP status Ught will illuminate. All others will be extinguished.
C: Correct: Per N2-0P-92 precaution 15, Placing an APRM slave (LPRM chassis) keylock switch in the INOP position will be detected by the APRM master and place the APRM channel in INOP Gust as if the APRM keylock switch has been placed in INOP). This will trip the OPRM input to the voter as well.
- A plant Startup is in progress with the following:
- All APRMs are reading 6%
- The Reactor Mode Switch is in STARTUP with final checks in progress for placing the mode switch to RUN.
Which one of the following identifies the effect, if any, of placing the IRM A Mode Switch (S1) in the Standby position on panel 2CEC*PNL606?
A. Nothing happens at this power level.
B. Annunciator IRM UPSCALE / INOPERABLE alarm only.
C. Control Rod block and Annunciator IRM UPSCALE / INOPERABLE alarm only.
D. Half scram, Control Rod block and Annunciator IRM UPSCALE / INOPERABLE alarm.
D: Correct: Taking the mode switch out of operate generates a half scram and rod block
- Primary Containment Isolation Valve testing is being conducted on containment purge AOVs in accordance with N2-OSP-CPS-Q001, Primary Containment Purge System Valve Operability Test.
Which one of the following would be the correct method for determining whether an AOV’s closure time was acceptable for a fully open AOV?
Start the timing when the … Stop the timing …
A. control switch is taken to the close ; when the green closed indication position illuminates
B. green closed indication illuminates ; when the red open indication extinguishes
C. control switch is taken to the close ; when the red open indication extinguishes position
D. green closed indication illuminates ; two seconds after red open indication extinguishes
A: Incorrect: This is the timing closed method for a CPS SOV.
Correct: Sect. 4.2.1 Measuring Valve Stroke times for all valves except Solenoid Operated Valves.
• Measure opening stroke time from the time the control switch is placed to OPEN until the green indicating light de-energizes.
• Measure closing stroke time from the time the control switch is placed to CLOSE until the red indicating light de-energizes.
- Which one of the following describes the electrical interlock with RHS*MOV2A, PMP 1A SDC SUCT VL V, and the reason for that interlock?
If RHS*MOV2A is OPEN then …
A. RHS*MOV24A, LPCI A Injection Valve, will not open to prevent bypassing the recirculation loop.
B. RHS*MOV4A, RHR Pump 1A Minimum Flow Valve, will not open to prevent draining the RPV to the suppression pool.
C. RHS*FV38A, RHR A Return to the Suppression Pool, will not open to prevent draining the RPV to the suppression pool.
D. RHS*MOV24A, LPCI A Injection Valve AND RHS*MOV40A, SDC A Injection valve, cannot both be opened at the same time to prevent running out the RHR pump.
C: Correct: If in SDC none of the suppression pool cooling Ispray valves can be opened.
- Following a Reactor scram the RO places the mode switch to Shutdown and commences inserting all IRMs and SRMs.
Which one of the following SRM alarms will occur?
A. • SRM Downscale
• SRM Detector Position Abnormal
B. • SRM Short Period
• SRM Upscale/Inoperable
C. • SRM Short Period
• SRM Detector Position Abnormal
D. • SRM Downscale
• SRM Upscale/Inoperable
B: Correct: An upscale trip is expected as the detectors are driven into the core and move into high flux regions. A short period is also expected. The detectors interpret the rise in counts as they are inserted as a short period.
- The plant is at rated power when the following occur:
- 2ENS*SWG101 de-energizes when Reserve Transformer 2 RTX-XSR1A locks out
- Diesel Generator 1 (EG 1) automatically starts
- EG 1 output breaker, 101-1, does NOT automatically close
Which one of the following is the potential impact of immediately attempting to manually close EG 1 output breaker, 101-1 and what actions are required by N2-S0P-3, Loss of AC Power, prior to manually closing the breaker?
Impact of Immediately Closing 101-1 ; Required Actions
A. Overloading EG 1 ; Place selected Bus loads in Pull to Lock ONLY
B. Energizing a faulted bus ; Verify there are no faults on the Bus ONLY
C. Overloading EG 1 ; Place selected Bus loads in Pull to Lock AND Place Bus 101 Synchronizing Switch to On
D. Energizing a faulted bus ; Verify there are no faults on the Bus AND Place Bus 101 Synchronizing Switch to On
D: Correct: A potential fault on 2ENS*SWG101 would prevent EG 1 from automatically closing on the bus. SOP-3 requires the operator to verify the bus is not faulted by verifying the bus fault annunciators (852147 and 852148) are clear. With EG 1 already running the procedure directs placing the Synch Switch in on and then manually closing the breaker.
- The reactor is at 100% power and 100% core flow when the following occurs:
- Main Turbine trip.
- RPS trips but NO rod insertion occurs.
- After the initial RPV pressure response, RPV pressure is stabilized between 970 psig to 1000 psig.
Which one of the following describes the amount of reactor power that is being generated 30 to 45 seconds after the transient begins and why power is lower than 100%?
(Assume that all systems, except rods, respond as designed but there continues to be zero rod motion and no operator actions have taken place other than stabilizing RPV pressure).
Approximate Reactor Power ; Basis for Power Lowering
A. Within Bypass Valve capacity ; Recirc pumps are at slow speed Recirc pumps are at slow speed
B. Greater than Bypass Valve capacity ; Recirc pumps are at slow speed Recirc pumps are at slow speed
C. Within Bypass Valve capacity ; Recirc pumps have tripped and Feedwater flow has runback
D. Greater than Bypass Valve capacity ; Recirc pumps have tripped and Feedwater flow has runback
D: Correct: The LFMG sets are tripped and the feed flow runback occurs 25 seconds after the high pressure trip. 30 to 45 seconds after the event occurs, with the recirc pumps tripped, reactor power lowers but remains >25% which is greater than bypass valve capacity.
- The plant is operating at rated conditions when a complete loss of CCP Mini-Loop cooling water to the Instrument Air system occurs.
What is the impact on the Instrument Air Compressors?
The operating Compressor trips on … Backup Compressors …
A. low cooling water flow… are blocked from starting.
B. high outlet air temperature… are blocked from starting.
C. low cooling water flow… start and eventually trip.
D. high outlet air temperature… start and eventually trip.
D: Correct: The compressors trip on high outlet air temperature. There is no interlock to prevent the lagging and backup compressors from starting. The backup air compressors will start and eventually also trip on high outlet air temperature.
- Which of the following components are cooled by the Condensate System?
1 . Offgas Condensers A and B
- Steam Jet Air Ejector Intercondensers
- Steam Jet Air Ejector Precoolers
- Mechanical Vacuum Pump Seal Cooler
A. Components 1 and 3
B. Components 2 and 4
C. Component 1 ONLY
D. Component 2 ONLY
A: Incorrect: Off gas condensers are cooled by TBCCW.
B: Incorrect: Mechanical Vacuum Pump Seal Cooler is cooled by Service Water.
C: Incorrect: Off gas condensers are cooled by TBCCW.
D: Correct: Steam Jet Air Ejector Intercondensers are cooled by the Condensate System.
- Which one of the following describes the potential effect of a loss of RDS Backfill Injection prior to a depressurizing event?
RPV water level indication will… PCIS water level isolations will occur. ..
A. indicate lower than actual… above the actual setpoint.
B. indicate lower than actual… below the actual setpoint.
C. indicate higher than actual… above the actual setpoint.
D. indicate higher than actual… below the actual setpoint.
D: Correct: RDS Backfill keeps the reference leg full of water and prevents the accumulation of dissolved gasses in solution that may come out of solution during sudden depressurization causing a loss of density in the reference leg that results in lowering the dp across the transmitter which correlates to indicated level being higher than actual. When indicated level lowers to 159.3, actual level is lower, therefore isolations that should have occurred at the actual level will occur below the actual water level.
- The plant is at rated conditions when annunciator 603303, ROD DRIVE CONTROL SYSTEM INOPERABLE, alarms.
Which one of the following describes the significance of this annunciator as it relates to the Reactor Manual Control System (RMCS) and the probable cause of this alarm?
Effect on Control Rod motion… Probable cause…
A. Rod motion is NOT impacted… Loss of RMCS permissive signal
B. Rod motion is NOT impacted… Loss of RDS Drive Water DP
C. Rod withdrawal is blocked… Loss of RMCS permissive signal
D. Rod withdrawal is blocked… Loss of RDS Drive Water DP
C: Correct: Per the associated ARP a rod block is generated to prevent rod motion when rod blocks may be disabled. The annunciator is caused by a:
- Low Voltage
- Computer Failure
- Master Test Pushbutton depressed
- Loss of permissive signal from (fcn. Of Rx Mode Switch):
a. RPIS (INOP)
b. NMS
c. RSCS
d. RWM
e. Scram Discharge Volume
f. Scram Discharge Volume Bypass
g. Refuel Platform
h. Service Platform - Clock Failure
- Twenty minutes after a fuel failure, reactor scram, and MSIV isolation, leakage past the MSIVs is indicated. Conditions are as follows:
• N2-EOP-MSL has been entered
• Main Condenser Vacuum is 0 inches
• Main Steam Line Radiation and Turbine Building Release limits of N2-EOP-MSL have been exceeded
Given these conditions, which one of the following system lineups is available to limit the escape of radioactive steam?
Place the …
A. Main Steam Line Drains in service.
B. Mechanical Vacuum Pump in service.
C. Bypass Opening Jack momentarily to open.
D. Steam Jet Air Ejectors in service utilizing Aux Boiler Steam.
D: Correct: N2-EOP-MSL directs that the SJAEs be placed in service per N2-EOP-6. EOP-6, attachment 16 lines up the SJAEs utilizing Aux Steam.