NOPs Flashcards
What rate of power reduction requires a RCS sample for iodine?
Any power change greater than or equal to 15% per hour
What is the setpoint and coincidence of P-8? What is the reset setpoint and coincidence?
Active when 3/4 power Range channels are less than or equal to 29%. (Permits auto block of “at power” trips).
Reset when 2/4 PR channels are greater than 29%
When is the interlock C-5 active?
Blocks auto rod withdrawal when turbine impulse pressure (MPC-253) is less than 15% equivalent power pressure
If Improper bank overlap occurred during the Rx shutdown, what actions would you take?
Notify MTI and SS of the problem but continue w the Rx shutdown until all roads are fully inserted and Rx trip breakers are open.
When one feed pumps speed is lowered what causes the other feed pump to speed up?
The FP speed controller compares feed hdr and steam hdr pressure difference to a programmed d/p value.
How many PR channels must be less than 10% in order to clear P-10 status light. What should be done if it doesn’t clear?
3/4 channels less than 10% clears the P-10 status light.
Corrective measure steps of the procedure should be performed.
Why are the steam dumps placed to steam pressure mode?
To align control system so that Tavg is maintained via steam pressure of the bypass hdr. This allows dumps to assume temp control as the turbine is unloaded and prior to being tripped.
Why should the high flux at shutdown alarm setpoint be changed?
Bc the neutron source strength is greater than it was when the reactor startup was performed
Why do we energize Pressurizer heaters 12 hrs before a planned power reduction?
Minimize the impact on RCS Hydrogen
Why are all available PRZ hers energized during a power change?
To minimize the PRZ and RCS loop boron concentration difference.
What can prolonged use of maximized pressurizer spray result in?
Hydrogen being stripped out of solution, requiring additions to VCT.
How many source range channels shall be in operation and recording continuously on NI Recorder SG-12 while the reactor is shutdown with fuel in the reactor?
Minimum of 2
Prolonged Turbine operation at less than 10% load must be avoided due to…..
Moisture erosion of last stage blades and exhaust hood heating
When the reactor is critical RCS temperature is maintained greater than or equal to 541*F. IF it falls below this temp, how long do you have to get it back and how do we do so?
30 minutes by reduction in steam demand.
What is the limit for rod movement above the POAH?
3 steps at a time until the associated reactivity effects are complete
What does it mean if P-10 remains lit with an inopeable power range channel?
- PR high flux low setpoint trip is not enabled
- IR high flux trip is not enabled
- SR detector voltage will not be restored below P-6 setpoint
Whose permission is needed if we plan on using SG PORVs as a planned method of RCS temp control?
Ops Director
Whose permission is needed for extended low-power operation?
Plant Manager
How can we alleviate potential issues with RCS Hydrogen?
Maintain VCT pressure at the high end of the band
How many NIs are required to perform Rx Startup?
Per TS: 2 SR, 2 IR, and at least 3 PR
How are the control rod urgent and non-urgent alarms reset?
At startup, the step counter reset can be used to reset the alarms.
After rod withdrawal begins, the alarm power reset at the cabinet must be used
Why are we required to perform ICRR plot during a reactor startup?
It’s a backup to the ECP. The prediction helps ensure that the critical rod position is above the Lo-Lo Insertion Limit, thus ensuring adequate SDM during startup
What indication will you observe when the reactor goes critical?
Power rising with a sustained positive start up rate with no rod motion
Why is the high flux at shut down alarm defeated before the reactor start up?
The alarm is there to alert the operator that an unplanned reactivity addition is occurring and should be investigated. A reactor start up is planned, and therefore the alarm is of no value and could be distracting if not blocked prior to start up
When do you expect the high flux at shutdown blocked annunciator to clear?
The alarm should clear as P-6 which is one out of two (1/2) intermediate range NIs at 10 E10 Amps
What is the basis for T average greater than 541°F prior to criticality
It ensures the following:
-MTC within analyzed range
-protective instrumentation and normal operating range
-pressurizer is capable of being operable with a steam bubble
-reactor pressure vessel is above minimum nil ductility temperature
How long will you wait after stopping rod motion before login data for the 1/M pot
Until the counter rate stabilizes
What is proper bank overlap and rod alignment?
Successive rod banks start moving when the preceding bank reaches 128 steps. All rods within a bank within 12 to 18 steps of the demand bank position
What is the zero power rod insertion limit?
128 steps on bank C or 0 steps on bank D
What rod height is associated with the ECP, the -1000 PCM position, and the +500 PCM position?
Refer to the ECP for correct answers. These values should also be written on the ICRR plot
What actions will you take if it appears the reactor will become critical below the rod insertion limit for zero power (LCO 3.1.6)?
Open reactor trip breakers, commence emergency boration, perform SDM calc, and determine the problem
As the start up has progressed, it has taken longer for the start up rate to fall to zero after rod motion has stopped. Why?
Sub critical multiplication process and the approach to KEff of one takes longer with more neutrons.
How do you recognize the point of adding heat?
Nuclear indication will show negative reactivity due to Doppler. RCS indications also rises in T average and pressurizer level. Steam generator pressure will rise and steam dumps will open
When during heat up and power escalation must an RCS leak rate be completed
Within 12 hours of establishing steady state operation in modes one through four. Therefore, the surveillance requirement should have been completed prior to entry into mode one.
As power level rises, what happens to the pressurizer reference level? Why?
Pressurizer reference level rises as T average rises. It is programmed to follow T average to minimize the mass change in the RCS with power. This reduces the amount of liquid rad waste.
When can rod control be placed in auto?
After power is above 15% and the C-5 interlock light is out
What is AFD?
AFD is the difference in normalized flux signals between the top and bottom halves of a two section excore neutron detector.
How is AFD calculated manually?
AFD can be manually calculated by recording each detector current, dividing each reading by that detectors 100% current reading, and subtracting the lower value from the upper value for each channel
What function does P8 perform?
When the P8 light is not lit, it will change coincidence of reactor trip due to low RCS flow from 2 loops to 1 loop and enables reactor trip from a turbine trip.
What is QPTR?
QPTR is the ratio of the highest normalized upper Excore detector output to the average of the upper Excor detector outputs. (or lower detectors)