Student Guide FRS Flashcards
(13 cards)
If SI is actuated during an ATWS, what is the only additional action the operators must take to ensure emergency boration?
Check RCS Pressure to ensure enough flow
What is a condition 2 event?
Event likely to occur but the plant will be able to be restarted. Will not cause consequential loss of fuel cladding or RCS FPBs
What is a ATWS?
A common cause failure that prevents the control rods from being inserted in response to an aniticpated event
During an ATWS event, what would cause a challenge to the Fuel/Clad Fission Product Barrier?
Most limiting event is a LOOP. Fuel could reach DNB due to loss of forced flow
During an ATWS event, what would cause a challenge to the RCS Pressure Boundary Fission Product Barrier?
Events initiated by a significant reduction in FW flow = rapids RCS Temp rise or events which the design capabilities RCS will be exceeded
List possible sources of positive reactivity in ATWS analysis?
Rods do not insert / cannot be
Cooldown from secondary
Dilution
Describe a Nuclear Generation Event?
Power generation - power removal mismatch
1) Loss of Load/Turbine Trip
2) Loss of Normal Feedwater
3) Loss of Offsite Power
4) Accidental RCS Depressurization
5) Uncontrolled RCCA Bank Withdrawal
List the FRS.1 immediate action steps and the basis:
Check Rx Trip - only RCP / Decay Heat
Actuate AMSAC - Turbine Tripped and AFW in service
Check TT - prevent uncontrolled cooldown. Turbine needs to be tripped within 30s to maintain SG
List major actions of FRS.1
Verify Auto Actions
Emergency Borate
Check for positive sources of reactivity
Verify subcritical
What is the basis for checking RCS pressure below PORV lift setpoint?
Ensure ECCS can inject and provide boration
What condition must be satisfied to exit FRS.1?
<5% log power and -SUR
What are the two causes of loss of subcriticality that FRS.1 will evaluate?
Cooldown
Dilution
What is the minimum AFW flowrate for adequate heat removal during ATWS?
450K pph
