4503 Flashcards
For RCS Flow instrumentation, how many pressure tapes on the LP Side?
3
For RCS Flow instrumentation, how many pressure taps are on the high pressure side?
1
If a leak develops on the high pressure tap for RCS Flow instrumentation, what does indication do?
The DP is smaller, so flow looks lower
How do you find core uncovery time?
Add both curves! Time to Boil + Uncovery
What is the RCS Heat up limit?
60 degrees per hour
What is the RCS Cooldown limit?
100 degrees per hour
How do RHR Hx Outlet valves IRV-310 and IRV-320 fail on a loss of control air?
Open
How does the RHR Hx Bypass valve, IRV-311 fail on a loss of Control Air?
Open
How does the RHR LD valve, IRV-300 fail on a loss of control air?
Closed
Which RHR Motor Ops can be used to control temperature if control air is lost?
ICM-311 and ICM-321
When in an ATWS (FR-S-1), when should RCPs be tripped?
Only when <5% power!
What are the unit differences for RWST Freeze protection?
Unit 1 is heat traced
Unit 2 has a pump and heater
What is the minimum temperature for criticality?
If < 541 degrees for 30 mins, Trip
If < 539 degrees, Trip immediately
What Loop and Leg does Normal charging go into
Loop 4, CL
What loop and leg is excess LD on?
Loop 4 CL
What loop and Leg is Normal LD on?
Loop 4 intermediate
What Loop and Leg is Alt Charging on?
Loop 1 CL
What loop and leg is RHR Suction on?
Loop 2 HL
How long of a time delay is there on a MFP Trip on low suction pressure?
5 seconds
What are the inputs to the sub cooling meter?
(5) Auctioneered High CETs or RVLIS WR Pressure
Auctioneered LOW RVLIS Pressure
Why is RVLIS Pressure Instrumentation desired as an input to the SC Meter?
Located outside of containment
What is the required RCS Leakage Detection Instrumentation per TS 3.4.15?
Containment sump monitor in each sump
1 containment atmosphere particulate rad monitor
1 containment atmosphere gaseous rad monitor
What are the RCS Flow related Rx Trips?
RCS Loss of Flow
UV RCP Busses
UF RCP Busses
RCP Breaker Position
When do you use NR RVLIS?
NO RCPS
When do you use WR RVLIS?
WITH RCPs
When do you use Upper Plenum RVLIS?
All RCPs Off
Which RCS Signal feeds directly into RIL Computer logic?
Auctioneered RCS Delta T
In excessive RCS Leakage AOP, which 3 conditions require a reactor trip?
- PRZ Level cannot be maintained w 2 CCPs (w LD Isolated)
- Containment pressure ~1 psi
- VCT Level cannot be maintained.
During a mode 4 Loca, what order is preferred to depressurization RCS to refill PZR?
- Normal Spray
- PRZ PORV
- Aux Spray
What is the overall strategy for injecting water into the RCS during a mode 4 loca?
Add 1 sources at a time, checking to see if PRZ Level and subcooling parameters are met before going to next source
Why not just inject everything you have at the same time in a mode 4 loca?
Too much water could result in solid RCS w large pressure transient that could cause an integrity issue
Will cross tying the SFP Hx prevent the SFP from boiling?
NO, just delays the time to boil
What is required for an irradiated fuel handling accident in the SFP area with no refueling activities in containment?
CR Notification
How is containment cooling provided w the loss of offsite power?
NESW via open cycle
If the TDAFP receives an auto start signal as part of a planned reactor trip, is it reportable?
YES!
RCS Flow should be maintained greater than 2400 gpm on IFI-311/321 OR > 3100 gpm on IFI-335. Why?
Ensure required mixing sot that a dilution event can be recognized
To help prevent surge line temp transients, net charging flow shall be limited to _____ with RCS Temp < 310 degrees
25 gpm
To help prevent surge line temp transients, net charging flow shall be limited to _____ with RCS Temp >310 degrees
75 gpm
During a heat up, why must control and shutdown rods not be energized until Tavg is > 500 Degrees?
Prevents a possible lockup situation due to thermal expansion or contraction of the rods and the CRDM
What can cause Actual Critical Rod Position to be lower than ECP?
Less boron in the core
Steam Pressure Controller set 5 psi lower than normal
Xenon, depending on core power history and time after shutdown
Why do we not use both trains of RHR at reduced inventory?
The potential of Air binding would risk damaging both pumps
What is required for LTOP w porvs and the suction relief?
Either 1 PORV and the suction safety
Or
Both PORVs
When in FRS1, why do we verify pzr pressure <2335 psig after commencing emergency boration?
To ensure 70 gpm + borates rwst water is injected thru the BIT injection valves
Which valve is associated with NPS-121?
ICM-129
Which valve is associated with NPS-122?
IMO-128
If there is degraded flow in a RCS loop due to a bad rcp impeller, what would be the result of the lowered flow rate?
Delta Temp in that loop at full power will be higher
And
The reactor core margin to DNB will be lower
If you get a RHR hx tube leak while using that train for shutdown cooling, what is expected?
Leaks into CCW. Lowers cavity level and raises CCW surge tank level. Also, less cooling bc that warmer water mixes w CCW
While moving fuel, an assembly is dropped in the pool. Bubbles are seen and there is a high rad on r5.
What happens automatically and what needs to be done manually?
Auto- fuel handling area supplies trip
Fuel handling charcoal filters were already in service but receive a signal.
Manually place CR pressurization fans in charcoal mode
What is the concern with the reactor trip breakers not opening during frs1?
FWI signal will not actuate to prevent excessive RCS cooldown from over feeding the SGs
What is c20? What does it do?
2/2 turbine impulse pressures > 40%
It enables amsac
When will you get an amsac actuation?
1/1 FW Flows to 3/4 SGs <25% and C20
What does an AMSAC initiation do?
Turbine trip
Mdafp start
Tdafp start
Afw flow conservation
Why is ATWS worse in BOL?
More positive MTC, which means less temperature feedback
During an ATWS, what 2 concerns are there? And which accidents make them the worst?
DNBR concerns from LOOP
RCS overpressure concerns from loss of normal feed water
Why is it important to get the turbine tripped in FRS1?
Preserve SG inventory for loss of normal FW ATWS
What would you expect to be the cause if RHR Amps were very low or even at 0?
Sheared shaft
What could the cause be of pegged high amps on a RHR pump?
Locked rotor
In terms of injection flow, what defines a LBLOCA vs a SBLOCA?
If RHR is able to inject, then it’s a LB
When swapping around RHR, why is the CL isolation valve closed before opening the HL valve?
Prevents pump runout
When does runout become a concern for the RHR pumps?
Flow beyond 4500 gpm
What are the RHR interlocks?
Yea, look these up asshole. I’m not typing em all out!
What are the time limits and reasons. associated w transferring to HL injection?
5.5 - 7.5 hours
Low end avoids core uncovery due to boil off
High end prevents boron precipitation
What elevation do we not operate RHR below?
614’
What will give you a SLI?
Low low Tave w high steam flow
High high lower containment pressure 2.8 psi
Low SG pressure <500 psi
What are the SG pressures that cause a reactor trip?
Unit 1
5%
15 % w high steam flow
Unit 2
22%
26% w high steam flow
What are some items that have thermal sleeves?
Prz spray and surge lines
Normal and alternate charging lines
RHR/ACCUM/SI Taps
