Loss Condenser Vacuum/PZR Failures Flashcards
What actions are taken for ERV failure or leak?
1) Close ERV Isolation
2) Trip RX if leakage exceeds capability to maintain RCS pressure
3) If leakage stops, continue operations. If not, perform leak rate, perform RPSD if leakage exceeds TS
4) PZR steam space > 1 gpm and unsafe then commence shutdown per 1102.016
5) If ERV or isolation inoperable then close ERV isolation, refer to TRM 3.4.2 and install caution tag
What actions are taken for leaking PZR code safety?
1) If leakage exceeds ability to maintain RCS pressure then trip reactor.
2) Refer to TS 3.4.10
3) Perform leak rate and perform RPSD if leakage exceeds TS limits.
4) If steam space leak greater than 1 gpm then if unsafe perform plant shutdown per 1102.016
Wat are the setpoints for PZR heaters?
Bank 3 ON @ 2135 and off at 2155
Bank 4 ON @ 2120 and off at 2140
Bank 5 ON @ 2105 and off at 2125
What actions are taken for PZR heaters inoperative?
1) Raise PZR level > 55”
2) Manually control heaters if not working in auto
3) If heater response slow check for steam space leak
4) Refer to PZR TS 3.4.9 and TRM 3.4.9
What actions are taken for PZR level malfunction indication?
1) Select valid level instrument on C04
2) Declare invalid instrument inoperable and refer to PAM spec if level differentiates > 16”
What indications/controls are driven from PZR level transmitter handswitch HS-1002?
What is the max temperature differential between pressurizer and spray fluid?
PER TRM 3.4.3 max delta T is 430 deg F.
What actions are taken for PZR spray valve failure?
1) If spray valve fails open attempt to close in manual and isolate using spray isolation valve if unable to close control valve. If both valves fail to close and RCS pressure dropping then ensure all PZR heaters on and reduce power to 40% at 10%/min. If all 4 RCPs running and load < 675 MW and power < 75% then secure P-32C. If 3 RCPs running and D secured then trip reactor and secure P-32C.
2) If spray valve fails closed, maintain steady state conditions and attempt to cycle valve in manual. If valve will NOT open then commence plant shutdown to make RB entry to attempt to cycle control valve locally.
What actions are taken for loss of all PZR level indications?
1) Adjust makeup flow using CV-1235 to maintain previous MU tank level slope.
2) Within 1 hour, commence SLOW power reduction (~10%/hr)
3) If PZR heaters are interlocked off then energize banks 1/2 at SCR cabinets
4) Monitor for indications of high or low PZR levels and adjust as needed.
What MW changes the condenser vacuum setpoint in which the turbine should be tripped and what are the vacuum values?
> 270 MW, Vacuum trip setpoint is 24.5”
< 270 MW, trip MANUAL trip setpoint is 26.5”
What are the transient low vacuum alarm setpoints?
26.7” and 24.7”
In Loss of vacuum at what setpoint is gland seal steam header pressure checked greater than and what action is taken?
If pressure < 75 psig then throttle open the Gland sealing steam bypass to establish 115 to 125 psig.
At what pressure does condenser vacuum pump automatically shift to hogging mode?
If in auto, 23”
At what pressure do the ADVs automatically control SG pressure?
21”
What actions are taken when vacuum is 5 to 17”?
Reduce MFPs to 1, reduce rx power < 3%, start AFW pump.
