incore Flashcards
Limits and precautions
Wait how long? (or for equilibrium) after a power change for using an incore readings. Wait 10 min for calibration purposes (rhodium decay)
5 minutes
The SPND signals are NOT reliable at the thermocouple temps > what temp?
1000 F
SPNDs should NOT be used for power dist calcs at powers < what power?
<15%
Use only 1 BIRO thermocouple at a time. With 2 selected, the average of the 2 will be used and the wrong corrected temperature will be applied?
true
Incore thermocouples range
0-2300 F
Incore thermocouples
Short or open circuit
Fails to reference temp
Incore thermocouples
Ref junction goes up
Low indicated temp
Incore thermocouples
Ref junction goes down
High indicated temp
During a power change, there is a delay in the incore signals. All readings are invalid for at least how much time?
6 minutes
PPC power supply normal
Swap to what supply on loss of main power with UPS
13.2kv, swaps to 1M 480V bus on loss of 13.2kv with UPS
Control room PPC power
ATB
How many sets of incore detectors
52
How many thermocouples
52
How many thermocouples available on ppc
50
How many thermocouples can also feed the BIRO
16
Thermocouple monitoring Biro may only select 1 at a time, if 2 are selected, what will be indicated?
The average of both will be indicated (average of whatever selected will be indicated)
9G is normally selected where?
On the BIRO
Tech specs
How many of how many incore thermocouples per quadrant must be Operable (how many total)?
2 of 4 BIRO incore thermocouples per quadrant must be operable (8 total).
2 of 4 biro incore thermocouples per quadrant must be operable, if not… restore in how long or be in what in how much time?
7 days, or be in HSD in 6 hours and CSD in 30 hours
Quadrant tilt
If exceed tilt limit, allowable power shall be reduced what percent for every what percent of tilt in excess of the tilt limit?
2% for every 1% tilt in excess of tilt limit
Quadrant tilt
When > what percent, monitor tilt every how many hours if tilt alarm INOP or 7 days otherwise
When >15% monitor tilt every 12 hour if tilt alarm INOP or 7 days otherwise
How many SPNDs, how many per how many elevations?
364
7 levels, 52 each level
Axial power imbalance
If an axial power imbalance is not achieved within 24 hours, RX power shall be reduced to < what prevent power? Within how much time
<40% power within 2 hours
When >40% monitor imbalance every how often? If alarm INOP, every how long otherwise?
Every 1 hour if alarm INOP, every 12 hours otherwise
Backup recorder power supply
VBC
How often for calibration for backup recorders?
Monthly for depletion correction
System operation
Computer failure
Minimum number of required number of individual incore detectors is how many?
23
System operation
RCITS: a minimum of how many incore thermocouples must be operable and in the core when the RCS is drained down below the tops of the hot leg outlet nozzels (RTDs) when reactor vessel head is installed
2 incore thermocouples
The delay associated with decay of Rh makes the SPND useable only under what conditions?
Steady state power conditions
What how long after a power change prior to using an incore SPND reading?
5 mins
Wait how long following a power level change before reading an incore SPND for calibration purposes
10 mins
How many thermocouples go to FIDMS, how many go to RCITS?
50 to FIDMS
2 to RCITS
FIDMS will substitute another SPND if one has not changed in how long when RX power is > what percent?
If one has not changed in a 6 minute time period when RX power >58%
Backup recorders receives inputs from how many SPNDs?
36
BIRO receives input from how many incore thermocouples, how many in each quadrant?
16, 4 per quadrant
Min per TS is 8, 2 per quadrant
How many SPND points required to be monitored at all time? How many for radial symmetry (quadrant power tilt), how many for axial symmetry (axial power imbalance)?
How many points used for both radial and axial?
Total for TS
16 for quadrant power tilt (radial) (8 in top, 8 in bottom)
9 for power imbalance (axial)(3 spnds in 3 strings)
2 points used for both
So 25-2 =23 spnds required for TS
Computer failure
If all 4 Nis (5/6/7/8) are operable, tilt and imbalance calcs may be made…
manually with OCDs per OP-TM-300-202
Computer failure
If only 3 NI’s (5/6/7/8) are operable imbalance can be calculated with this instrumentation per what, however tilt will need to be calculated using what?
Imbalance calculated manually with OCDs per OP-TM-300-202
However,
Titl will need to be calculated using MIS (backup recorders) per OP-TM-300-203
Computer failure
If less than 3 NI’s (5/6/7/8) are operable, then tilt and imbalance need to be caulcated using what?
Tilt and imbalance will need to be calculated using MIS (backup recorders) per OP-TM-300-203
SPND signals should not be used for power distribution calcs at power levels less than what percent?
15%
