Engineered Safety Features Flashcards
TRA00083
What is the purpose of the ESF?
Active devices and associated equipment initiating their action which function with passive structures of the plant to prevent the unacceptable release or spread of radioactive materials by preventing plant variables or conditions from reaching their respective safety limits, or by mitigating the consequences of exceeding safety limits.
What are the ESFs?
- EFIS
- Vessel Level Alarm
- Rad Monitoring and Seal System
- Pump Shutoff ESF
- Vessel Vent System
- Primary Reliefs
What are the 3 subsystems of Pump Shutoff ESF?
- Primary Pump Shutoff
- PZR and GSW Shutoff
- LOCA PCP Shutoff
What is the purpose of EFIS?
Inject firewater into the RV when other methods of cooling are inadequate.
What accidents does EFIS mitigate?
- LOCA
- CLOFA
- CLOHS
Describe EFIS pressure injection reset.
No auto reset. Continues to inject until manually reset.
Trip at 30 psia.
Adjustability of EFIS functions?
Both EFIS level and pressure are adjustable.
Describe EFIS level injection reset.
Auto reset.
Adjustable setpoint and reset.
Describe actuation logic for Low Vessel Pressure EFIS.
2/3 Pressure channels tripped
Manual Reset
Trip at 30 psia
Describe actuation logic for Low Level EFIS.
2/3 Level channels tripped
Auto Reset at 92’ 3.6”
Trip at 88’6”
Where can EFIS be manually actuated?
Either RCR or RMC if active.
Each system flows 2000 gpm
What happens when EFIS level reset occurs?
Firewater injection valve closes.
When is EFIS level system required to be operable?
Anytime irradiated fuel is in the RV.
When is EFIS pressure system required to be operable?
Anytime PCS pressure is above atmospheric and irradiated fuel elements are in the RV.
Where is EFIS pressure injection bypassed from?
PPS rooms A/B/C/D
Where are Pump Trip ESFs located?
PPS rooms A/D
Where is Pump Trip bypassed from?
PPS rooms A/B/C/D
OE on EFIS pressure actuation?
Don’t rely on expert-based performance.
What PPS power supplies Upper and Bottom head EFIS solenoids?
PPS C battery - Upper
PPS A battery - Bottom
Describe direct water supply to EFIS from deepwell.
Through L-14/15 into firewater pipes through L-8.
Where are upper efis valves located?
1st basement south side near 1C-W primary secondary wall
Where are bottom head efis valves located?
Rod Access
Describe firewater injection upper and bottom manual trip monitors.
Meters display 0.8 when EFIS valves are shut.
Meters display 0.0 when manually actuated.
Meters display 1.0 when tripped by PPS actuation.
Purpose of RMSS
Seal confinement area from the environment.
