CEDMCS Flashcards
During a reactor startup, which of the following describes the required action if criticality is achieved above the PDILs and below the -500 pcm position?
A. Insert regulating groups to their lower group stops.
B. Stabilze power and take critical data.
C. Insert ALL CEAs to their lower group stops.
D. Immediately trip the reactor and commence boration.
Answer: A
Unit 1 is operating at rated power. Subgroup 5 has been transferred to the hold bus. The ‘B’ Main Feed Pump trips. Which of the following describe the plant response?
A. A RPCB will initiate with group four providing sufficient negative reactivity to offset the reduction of feedwater.
B. A normal RPCB will be initiated.
C. The reactor will trip if group 5 is not inserted manually within 40 seconds following the RPCB signal.
D. The reactor will trip immediately.
Answer: D
Unit 1 is operating at rated power A Regulating Group 5 CEA has been determined to be UNTRIPPABLE (STUCK) The Operating Crew is reviewing the Tech Specs associated with this problem While they are performing this, a trip of the ‘B’ MFP occurs Based on this, which ONE of the following describes how the plant will respond?
A. The reactor will trip immediately.
B. A normal RPCB will be completed.
C. The reactor will trip in approximately 30 seconds.
D. A RPCB will occur, however a building penalty factor will eventually (within 10 minutes) lead to a plant trip.
Answer: A
Unit 1 is operating at rated power with ARO. A Regulating Group 3 CEA (non twelve finger) slips to 138 inches withdrawn. A Regulating Group 5 CEA slips to 145 inches withdrawn. The operating crew is required by procedure to …
A. reduce turbine load to maintain Tave and Tref within 5 degrees of each other and reduce reactor power within 10 minutes.
B. trip the reactor and implement the SPTAs.
C. reduce turbine load to maintain Tave and Tref within 3 degrees of each other and reduce reactor power within 20 minutes.
D. reduce turbine load to maintain Tave and Tref within 3 degrees of each other and reduce reactor power within 10 minutes.
Answer: D
In response to a Continuous Gripper High Voltage alarm an operator is transferring a subgroup to the hold bus, what operator action actually removes the continuous high voltage?
A. Closing the individual CEA breakers on the Hold Bus Power Switch Assembly.
B. Operating the hold bus transfer toggle switch.
C. Selecting the appropriate subgroup on the SG/SEL thumbwheel.
D. Opening the individual CEA circuit breakers on the associated subgroup Power Switch Assembly.
Answer: D
Unit 1 is operating at 100% power. A Regulating Group 4 CEA drops to the bottom of the core. Based on these conditions, the operating crew must:
A. begin efforts to restore the CEA in 10 minutes.
B. have the CEA restored within 15 minutes.
C. be less than 80% power within 30 minutes.
D. begin a power reduction within 10 minutes.
Answer: D
Unit 1 is operating at rated power with all rods 150 inches withdrawn. A Regulating Group 3 CEA slips to 135 inches withdrawn. Shortly after this, a Regulating Group 5 CEA drops to the bottom of the core. Based on these conditions, the operating crew must:
A. monitor CPC DNBR and LPD margins to trip and trip the reactor if either one approaches its trip setpoint.
B. monitor CPC ASI and trip the reactor if it approaches +0.5.
C. reduce turbine load to maintain Tavg and Tref within 3°F of each other.
D. immediately trip the reactor.
Answer: D
The function of the Dropped Rod Contact (DRC) is to…
A. stop all rod motion in any CEDMCS mode.
B. reset the individual CEA pulse counter.
C. reset Reactor Power Cutback (RPCB) flag in COLSS.
D. initiate an auto reactor trip if two or more rods drop in the core.
Answer: B
Plant is at 100% power I&C is testing the UV detectors at the CEDMCS control panels The Tech depresses the UV1 test pushbutton, the UV light illuminates Upon release of the test button the UV light remains illuminated The Tech then depresses the UV2 test button Besides sending signal to the SBCS for a Quick Open Block Permissive which of the following occur?
A. The Feedwater Control system will shift to Reactor Trip Override.
B. Nothing else will occur.
C. RTSG Breaker 1 will open but no reactor trip will occur.
D. RTSG Breakers 1 and 4 will open causing a reactor trip.
Answer: A
Plant is at 100% power An I&C technician is testing the UV detectors at the CEDMCS control panels When the UV1 test pushbutton is depressed, the UV light illuminates. Upon release of the test button the UV light remains illuminated. The UV2 test button is then depressed. Besides placing DFWCS in RTO which of the following occur?
A. an ATWS occurs
B. the turbine will trip
C. a reactor trip is inititiated
D. RTCB’s 1 and 3 (only) will open
Answer: B
There are two rows of amber card status LED indicators located on each CEDMCS subgroup logic housing front panel. These indicators will:
A. come on if the corresponding circuit board fails its internal timing test every six seconds
B. go off if the corresponding circuit board is not fully seated in its connector or when an incorrect type of card is installed in the indicated position
C. come on if the corresponding circuit board is not fully seated in its connector or when an incorrect type of card is installed in the indicated position
D. go off if the corresponding circuit board fails its internal timing test every six seconds
Answer: C
There is a row of red timer failure LED indicators located on each CEDMCS subgroup logic housing front panel that…
A. extinguish to indicate a timer card has failed.
B. light to indicate a timer card has failed.
C. light to indicate a timer card has lost its sync with the master timer.
D. extinguish to indicate a timer card has lost its sync with the master timer.
Answer: B
The subgroup assigned to Regulating Group 5 has been transferred to the hold bus. The associated power switch has been removed from the cabinet for repair. A Reactor Power Cutback initiates due to a loss of a main feed pump and the RPCB system has commanded the Reg Gp 5 subgroup to drop. Reg Group 5 will initially…
A. remain in position.
B. drive in auto sequential.
C. drop as commanded by RPCS.
D. remain in position until the operator attempts to drive the Reg Gp 5 subgroup in, causing the subgroup to drop.
Answer: A
Plant is at 40% power after a RPCB A CWP has been received CEDMCS in AUTO sequential. If the operator pushes and holds the CWP bypass button, CEAs can…
A. be withdrawn in any mode except standby.
B. NOT be withdrawn in any mode.
C. be withdrawn in manual individual only.
D. be withdrawn in manual group or manual individual only.
Answer: A
The function of the Dropped Rod Contact (DRC) is to:
A. Stop all rod motion in any CEDMCS mode.
B. Initiate an auto reactor trip if two or more rods drop in the core.
C. Reset the individual CEA pulse counter.
D. Reset Reactor Power Cutback (RPCB) flag in COLSS.
Answer: C