4501 & 4502 Flashcards
Why should the Integrity status tree be disregarded during E-3?
False reading possible in ruptured loop CL indication w no RCPs during a SGTR. This is because of pooling.
Why will SG Level rise more quickly with RCPs tripped?
Less heat transfer because the SG is not steaming as much.
Why is there an overfill concern during a SGTR with no RCPs?
Loop transport times will result in a slower cool down
When cooling down in E-3 using the dumps, what should you not do? And why!?
Do NOT use Turbo bc it can cause a SLI
What is the purpose of getting the Pressurizer to the saturation temperature of the ruptured SG pressure?
To minimize flow between the RCS and SGs
What is the equation for figuring out a new leak rate after a change in pressure?
Leak 2 / Leak 1 = (square root of DP2) / (square root of DP1)
If you lose 2 PR NIs, what happens?
It takes out your source range and will trip you during a start up (
What are OTDT inputs?
DT
Tave
AFD
Pzr pressure
What does OTDT protect from?
DNB
What are the inputs to OPDT?
DT
Tave
What does OPDT protect from?
KW/Ft
At 8% power and under compensated, what does this look like? Why?
Both intermediate range NIs look the same because neutrons are overwhelming.
After a trip, what do the intermediate range NIs look like if one was under compensated? What does this prevent?
The NI that is under compensated will give a false high indication. The intermediate range current will stay above the P6 setpoint, preventing the source range detectors from auto energizing
What is the back up auto deenergization for the source range NIs?
P10
At 100% power, what happens if a power range NI fails off scale high?
Rods will insert, but they will not come back out because of the C2 Rod stop
When above the point of adding heat, what does moving rods cause?
The reactor power will follow steam demand
When below the point of adding heat, what will moving rods do?
Adds reactivity, but no effects are seen
What does bank overlap provide?
More uniform AFD and more uniform differential rod worth
What is QPTR for?
Radial flux
What will a dropped rod affect?
QPTR AND RADIAL FLUX
What will maintaining a AFD and QPTR do for us?
It will maintain power density and DNB in spec
If above 90% power and not within the target band what must we do per tech spec?
Get back within target band or below 90% power within 15 minutes
Must be either less than 90% or back within target band within an additional 15 minutes
If you cannot accomplish target band within a total of 30 minutes, you must be under 90% power!
What happens to voltage and current if you lose a battery charger and you were on the battery?
Voltage will go down
Current will go up
How long is the 250 V DC battery good for during a loss of offsite power?
3 hrs
How long is the 250 V DC battery good for during a Station black out?
4 hrs
If you have CCW in or out leakage when on RHR, what must you do within one hour?
SDM
If there is a fire on the unit one main transformer, how many fire pump should be running?
2
What are the manual actions that must be taken during a main transformer fire if parallel to the grid?
Trip the generator and verify deluge actuates
Turbine trip if < P8
Reactor trip if > P8
If the control room is destroyed and you are in the SAMGs, what would you prioritize the use of an AEO for?
Starting TDAFP
What would be an entry condition for SAMGs?
CETCs >1200 degrees
During SAMGs, why is it important to maintain SG Level?
To prevent creep rupture failure
During a large break LOCA, what are the consequences if the contents of the spray add tank are not used?
Iodine will not be kept in solution
During a large break LOCA, what happens if too much of the spray add tank contents are put in?
Chloride and caustic stress corrosion of equipment can occur
Which Signal causes a CTS pump to start?
Phase B
Which signal causes the valves to realign for the CTS system?
CTS signal
If unable to verify natural circulation, what should be done?
Raise steam demand. Dump more steam with the steam dumps
What can interrupt natural circulation?
Voids. Monitor using the NR RIVLIS
What is the potential outcome from over filling the steam generators in E3?
May rupture the main steam line from weight of water and water hammer.
This could damage the PORVs, safeties and TDAFP as well
Why is the SG PORV’s set point changed to 1040 psig during E3?
Minimize release
When in E3, under what conditions is there a release in progress?
ALWAYS!
Which factor of the 5 factor formula is affected most by control rods?
Thermal utilization factor
What happens to control rod worth as moderator temperature rises?
It goes up
What happens to rod worth over core life? Why?
Rod worth goes up.
Less boron due to fuel burn out, less competition between the control rods and boron, and neutrons are more likely to be absorbed by the control rod
What do you rod insertion limits ensure?
That rods will be more withdrawn as reactor power rises to compensate for the change in power defect
What will cause the reactor to trip on the loss of 250 V DC?
RCP Bus under frequency because 250 V DC powers it’s relays
What is the input to the main feed pump DP program variable support
Total steam flow
What point does the rod insertion limit comparator use?
Auctioneered High Delta T power
At the bottom of the core is DNBR higher or lower? Why?
Higher because temperature is cooler
Where in the core is DNBR the lowest?
Upper mid plane because more heat flux is occurring in that region
What is the purpose for the basis for the limit on maximum linear power density?
To provide assurance of fuel integrity
What are the dose limits for EDMGs?
5 Rem Whole body for damage assessment
10 Rem whole Body per incident to protect valuable equipment
25 Rem whole body lifetime for lifesaving
If you manually actuate the CTS gold switches, what happens?
CTS signal
Phase B signal
CVI
NO Steam line isolation!
Where is the 2.8 psi sensed that gives you a CTS, SLI and phase B signal?
2/4 in LOWER containment
Which valves reposition on a CTS signal?
CTS pump discharge valves and the spray add tank valves.
Heat exchanger valves only reposition when also on recirc sumo
What will the spray add tank lo lo level do?
Closes the spray add tank outlet valves and eductor valves
Why should the hydrogen Recombiners not be started while in modes 1-4?
Concerns with overloading the EDG
Why are the CRDM fans placed in stop and lower containment fans placed to off during CTS?
To prevent them from restarting when phase B is reset, does possibly overloading the EDG
Why wait 50 mins to put RHR spray in service when only having one train of CTS?
Because decay heat is low enough that one safety injection pump and one charging pump are sufficient to cool the core
What happens to pressure and flow when centrifugal charging pumps are in series?
More pressure
What happens to pressure and flow when centrifugal charging pumps are in parallel?
More flow
What happens when positive displacement pumps are in series?
No change in Flow
What happens to positive displacement pumps when in parallel?
Flow is additive
What are the pump laws?
Flow ~ Speed
Head ~ Speed ^2
Power ~ Speed ^3
When should RCPs be stopped for the best natural circulation flow?
Closer to the trip
What cools the head during natural circulation?
CRDM Fans
