ADS/SRVs

Card Set Information

Author:
heidin
ID:
141743
Filename:
ADS/SRVs
Updated:
2012-03-15 11:36:22
Tags:
ADS SRVs ILC
Folders:

Description:
questions
Show Answers:

Home > Flashcards > Print Preview

The flashcards below were created by user heidin on FreezingBlue Flashcards. What would you like to do?


  1. Unit Two has a small line break in the drywell. Conditions are as follows:

    RPV Level 35" (N026A/B)
    RPV Pressure 980 psig
    Drywell Pressure 6 psig
    Div I and II PNS Pressure 125 psig
    Div I and II B/U Nitrogen System 115 psig

    Based on these conditions and without the use of any overrides, the continuous pneumatic supply to the SRVs is from:

    A. PNS only.
    B. Backup Nitrogen only.
    C. Either PNS or Backup Nitrogen.
    D. Neither PNS nor Backup Nitrogen.
    B. Backup Nitrogen only.


    A LOCA signal exists from low RPV level. The LOCA signal closes RNA isolation valves (group 10) to the drywell. The signal is also sent from RNA isolation valve logic to open the backup nitrogen valves. Backup Nitrogen is considered to provide a continuous supply as long as header pressure in either division remains above 95 psig.
  2. During an event with limited high-pressure injection, reactor water lever has dropped below LL3 resulting in initiation of the ADS timer. An operator observes ERFIS Display 241 (SRV Status) ADS Timer status turn from green "No ADS lnit", to yellow" ADS Timer Ener", then back to green "No ADS lnit".

    What could cause this display? The ADS timer:

    A. is running, but is not yet timed out.
    B. started, but then ADS was inhibited.
    C. has timed out, and ADS has initiated.
    D. has timed out, but ADS has not initiated.
    B. started, but then ADS was inhibited.


    Green No ADS Init means the timer is not running, yellow ADS Timer Ener means the timer is energized but 83 seconds have not passed. Red ADS Init means the timer has timed out (whether ADS has actually initiated or not). If level drops below LL3 the display turns from green to yellow. Inhibiting ADS will de-energize the timers, and the display would turn back green.
  3. During startup of Unit Two from a refueling outage, the following reactor pressures were reached at the indicated times:
    At 0400, reactor pressure reaches 150 psig.
    At 0800, reactor pressure reaches 945 psig.
    Surveillance requirement 3.5.1.11 is required. Which of the following describes Technical Specification requirements for completion of this surveillance?

    A. The surveillance must be performed by 1600. Mode 1 cannot be entered until the surveillance is performed.
    B. The surveillance must be performed by 2000. Mode 1 cannot be entered until the surveillance is performed.
    C. The surveillance must be performed by 1600. Mode 1 can be entered without the surveillance being performed.
    D. The surveillance must be performed by 2000. Mode 1 can be entered without the surveillance being performed.
    D. The surveillance must be performed by 2000. Mode 1 can be entered without the surveillance being performed.


    ADS is required by LCO 3.5.1 to be operable prior to exceeding 150 psig. SR 3.5.1.11 performance requirement is modified by a note and per SR 3.0.1 is not required to be performed until 12 hours after reactor pressure is sufficient to perform the test. Per the bases for SR 3.5.1.11, adequate pressure to perform the test is 945 psig, thus the 12-hour clock starts at 0800 (requiring completion by 2000). SR 3.0.4 does not apply for entry into mode 1 since the surveillance is not required for 12 hours after 945 psig. (Also, this surveillance is performed using PT-11.1.2. This PT specifically requires the reactor be in Mode 1)
  4. An MSIV closure isolation has occurred. Reactor water level is +170 inches and reactor pressure is 1000 psig. A Safety Relief Valve is opened to reduce reactor pressure.

    As the Safety Relief Valve opens, reactor water level indication will:

    A. rise due to void formation. Temperature of steam in the tailpipe will indicate approximately 350°F.
    B. rise due to void formation. Temperature of steam in the tailpipe will indicate approximately 545°F.
    C. lower due to void collapse. Temperature of steam in the tailpipe will indicate approximately 350°F.
    D. lower due to void collapse. Temperature of steam in the tailpipe will indicate approximately 545°F.
    A. rise due to void formation. Temperature of steam in the tailpipe will indicate approximately 350°F.


    Opening an SRV will cause rapid drop in pressure in the vessel, formation of voids, and subsequent swell in reactor water level even though more inventory is being removed from the RPV. The throttling of steam through the SRV is a constant enthalpy process. At atmospheric pressure the steam would be approx 300°F, with backpressure in tailpipe the theoretical temperature at the thermocouples is approx 350°F per SD-20.
  5. Unit Two was at rated power when off-site power was lost. Plant conditions are:

    Unit One buses remain powered from off-site power.
    DG3 and DG4 failed to start and E3 and E4 are de-energized.
    Reactor water level has been below LL3 for 2 minutes and is currently +25 inches.
    RHR pump 2C is under clearance and RHR pump 2D is running.
    The ADS Inhibit Keylock switches are in Normal.

    DG4 then becomes available, starts and energizes E4. When will ADS valves open?

    A. When RHR pump 2B starts.
    B. When Core Spray pump 2B starts.
    C. 83 seconds after RHR pump 2B starts.
    D. 83 seconds after Core Spray pump 2B starts.
    A. When RHR pump 2B starts.


    For ADS to initiate, the logic must see a low pressure ECCS permissive, either one Core Spray, or both RHR Pumps in a loop. With RHR Pump 2D the only running LP ECCS, this permissive is not met. The 83-second ADS timer, however, does not need to see the LP ECCS permissive to start timing, only LL3 with confirmatory LL1. With level below LL3 for 2 minutes the timer has timed out. The logic will energize and open as soon as the ECCS permissive is met. Since RHR sequences at 10 seconds from bus energization, and Core Spray sequences 5 seconds later, the ADS valves open when RHR 2B sequences on.
  6. Unit Two just entered a shutdown LCO due to HPCI and RCIC being inop, when a Loss of Off-Site Power occurs. EDGs 3 and 4 fail to start. Unit One buses E1 and E2 remain energized throughout the event. Pressure is being maintained 800-1000 psig using SRVs. Level has been below 45 inches for 5 minutes and is currently +25 on the N026’s.

    Assuming ADS was NOT inhibited, which ONE of the following describes how ADS would respond to #4 EDG starting?

    7 ADS valves would auto open seconds after the diesel tied to E4.


    A. 10
    B. 15
    C. 83
    D. 93
    A. 10
  7. During normal power operation of Unit 1, SRV F013H lifted. Which ONE of the following describes the consequences of SRV F013H tailpipe vacuum breaker (F037H) failing open prior to the SRV actuation?


    A. Steam will discharge directly to the suppression pool air space
    B. Steam will discharge directly to the drywell
    C. Water from the suppression pool will be drawn into the SRV tailpipe following actuation.
    D. A redundant vacuum breaker will open with no consequences.
    B. Steam will discharge directly to the drywell
  8. Which ONE of the following describes the normal electrical power supply for Safety Relief Valve solenoids on Unit Two (2)?

    Div I DC
    Div I AC
    Div II DC
    Div II AC

    ONE (1) of the following describes the RHR Pump input to ADS logic?


    A. Transmitters from pumps A and C provide signals to the "A" logic system. Signals from pumps B and D provide inputs to the "B" logic system.


    B. Transmitters from pumps A and D provide signals to the "A" logic system. Signals from pumps B and C provide inputs to the "B" logic system.


    C. Transmitters from pumps B and C provide signals to the "A" logic system. Signals from pumps A and D provide inputs to the "B" logic system.


    D. Transmitters from pumps B and D provide signals to the "A" logic system. Signals from pumps A and C provide inputs to the "B" logic system.
    D. Transmitters from pumps B and D provide signals to the "A" logic system. Signals from pumps A and C provide inputs to the "B" logic system.
  9. When steam is discharged from the safety relief valves (SRV) to the suppression pool water, which ONE (1) of the following describes the flow path taken by the SRV discharge and the reason for the path?


    A. SRV discharges to a tailpipe which terminates in a manifold (T-Quencher) approximately seven feet below normal suppression pool water level. This provides even heat distribution in the suppression pool and reduced dynamic forces on the suppression chamber.
    B. The SRV discharges to a tailpipe which terminates in a manifold (T-Quencher) approximately seven feet above the bottom of the suppression pool. This provides even heat distribution in the suppression pool, but does not significantly reduce the dynamic forces.
    C. SRV discharges to a tailpipe which connects to a ring header, the ring header terminates in a manifold (T-Quencher) approximately seven feet below normal suppression pool water level. This provides even heat distribution in the suppression pool, but does not significantly reduce the dynamic forces.
    D. SRV discharges to a tailpipe which connects to a ring header, the ring header terminates in a manifold (T-Quencher) approximately seven feet above the bottom of the suppression pool. This provides even heat distribution in the suppression pool and reduced dynamic forces on the suppression chamber
    A. SRV discharges to a tailpipe which terminates in a manifold (T-Quencher) approximately seven feet below normal suppression pool water level. This provides even heat distribution in the suppression pool and reduced dynamic forces on the suppression chamber.
  10. RVCP Reactor Vessel Control Procedure. Conditions are as follows:

    Reactor Water Level 40” and lowering slowly
    Reactor Pressure 850 psig lowering slowly
    AUTO DEPRESS RELAYS ENERGIZED A-03 (3-2) In Alarm
    AUTO DEPRESS TIMERS INITIATED A-03 (5-1) In Alarm
    ADS valve position indication All Green ON, All Red OFF

    The SRO has determined that reactor water level can be restored and maintained above Top of Active Fuel (TAF) with available injection sources and directs the RO to place the ADS inhibit switches to “INHIBIT”.

    Which ONE of the following describes the effect that placing the ADS inhibit switches to “INHIBIT” has on the ADS?

    Placing the ADS inhibit switches to “INHIBIT” will de-energize ADS:


    A. logic relays and timer relays. Alarms A-03 (3-2) and A-03 (5-1) will clear.
    B. logic relays and timer relays. Alarms A-03 (3-2) and A-03 (5-1) will remain in alarm.
    C. logic relays ONLY and A-03 (3-2) clears. ADS timer relays will remain energized and A-03 (5-1) remains in alarm.
    D. timer relays ONLY and A-03 (5-1) clears. ADS logic relays will remain energized and A-03 (3-2) remains in alarm.
    A. logic relays and timer relays. Alarms A-03 (3-2) and A-03 (5-1) will clear.
  11. Unit 1 has just received annunciator A-3 2-2 AUTO DEPRESS CONTROL POWER FAILURE. Subsequent investigation reveals no light indication for any ADS/SRV at panel P601. Based on these indications which ONE (1) of the following is the probable cause and how is ADS/SRV operation affected?


    A. Loss of DC power supply from panel 3A only. ADS Logic "B" and ADS/SRV solenoids have normal power from panel 3B. ADS and SRV pressure relief will function.
    B. Loss of DC power supply from panel 3B only. ADS Logic "B" and ADS/SRV solenoids have alternate power from panel 3A. ADS and SRV pressure relief will function.
    C. Loss of DC power supply from panel 3A and 3B. ADS logics and ADS/SRV solenoids have no power. SRV pressure relief will function.
    D. Loss of DC power supply from panel 3A and 3B. ADS logics and ADS/SRV solenoids except SRV "D" have no power. SRV pressure relief will function and SRV "D" is operable from Panel P601.
    C. Loss of DC power supply from panel 3A and 3B. ADS logics and ADS/SRV solenoids have no power. SRV pressure relief will function.
  12. Unit One is at rated power when a Loss of Off-Site power occurs. Sequence of events is as follows:

    T=0 seconds Off-site power is lost
    T=2 seconds RPV pressure peaks at 1135 psig
    T=7 seconds All open SRVs reclose
    T=10 seconds DGs 1 & 2 tie to their respective E Buses

    During this transient how many SRVs have lifted and how many amber memory lights are lit?
    4 SRVs have lifted but no amber memory lights are lit.
  13. Unit 1 is operating at power with Core Spray Pump 1B under Clearance. A loss of Off-site Power occurs to BOTH units. Diesel Generators 2 and 4 auto start, Diesel Generators 1 and 3 trip and lockout.

    A stuck open SRV and loss of high pressure injection cause reactor level to lower. All available low pressure ECCS pumps have been manually started. Plant conditions are:

    Reactor water level LPCI/Core Spray initiation signal just received
    Reactor pressure 800 psig
    Drywell pressure 0.6 psig
    ADS Inhibit Switches AUTO

    Assuming NO operator action, ADS will:


    A. Auto initiate in 83 seconds.
    B. Auto initiate in 105 seconds.
    C. NOT auto initiate due to lack of high drywell pressure.
    D. NOT auto initiate due to lack of ECCS pump pressure.
    A. Auto initiate in 83 seconds.
  14. Unit 1 has experienced a LOCA, conditions are:

    7 ADS valve control switches OPEN / ADS INITIATED
    ADS Logic Inhibit switches Auto
    RPV level 200”, steady
    RPV pressure 150 psig, slowly lowering
    Drywell pressure 6 psig, lowering

    The RO secures all low pressre ECCS pumps to control RPV level.

    The RO has not depressed the ADS timer reset pushbuttons. The ADS valves will close:


    A. Immediately
    B. Only after RPV pressures reaches approximately 56 psig.
    C. Only after the RO places the 7 ADS valve control switches in AUTO.
    D. After RPV pressure reaches approximately 56 psig or immediately if the RO places the ADS valve control switches in AUTO.
    D. After RPV pressure reaches approximately 56 psig or immediately if the RO places the ADS valve control switches in AUTO.


    The switches in “open” will hold the valves open until RPV press is ~50#.The switches in “auto” – the logic is no longer made up.
  15. Unit Two plant conditions following an automatic initiation of ADS are as follows:

    Reactor level -20 inches
    Reactor Pressure 400 psig and lowering
    Core Spray pumps 2A and 2B pumps running
    ADS SRV's 7 ADS valves OPEN with control switches in AUTO

    A dual unit loss of off-site power occurs and all DGs tie onto their respective E buses.

    Which one of the following predicts how the ADS valves will respond during the loss of
    offsite power and subsequent re-energization of power to the E-busses?


    remain open when the LOOP initially occurs;
    remain open after the E-Busses are re-energized.
    B. close when the LOOP initially occurs;
    remain closed after the E-Busses are re-energized.
    C. close when the LOOP initially occurs;
    re-open 83 seconds after the. Core Spray pumps restart.
    D. close when the LOOP initially occurs;
    re-open immediately after the Core Spray pumps restart.
    D. close when the LOOP initially occurs; re-open immediately after the Core Spray pumps restart.


    ECCS pumps will trip on UV will LOOP. With Control Switches in AUTO, valves will close due to loss of ECCS permissive in ADS logic. Since RPV water level is still below LL3, valves will re-open when ECCS pumps sequence back on and re-satisfy the ECCS permissive. ADS timer stays sealed in (timed out) when ECCS permissive is lost.
  16. Which one of the following describes the effect that a loss of E8 will have on the Unit Two Safety Relief Valve (SRV) system?


    A. Inability to manually operate SRV's from the RTGS
    B. Inability to manually operate SRV's from the RSDP
    C. Loss of SRV position indication on the RTGB
    D. Loss of SRV position indication on the RSDP
    C. Loss of SRV position indication on the RTGB


    SRV position indication on the RTGB is powered thru the acoustic sensors that are powered from E6/E8.

What would you like to do?

Home > Flashcards > Print Preview