Reactor Trips

Question 1

Source Range Hi Flux Rx Trip

→What does it protect against?
→Setpoint?
→Coincidence?

Answer 1

Source Range Hi Flux Rx Trip

→Startup Accident
→≥10^5 cps
→1/2 Source Range Detectors

Question 2

Source Range Hi Flux Rx Trip

Notes/What does it do?

Answer 2

Source Range Hi Flux Rx Trip

→Can be manually blocked (2/2 switches) when P-6 is met.
→Auto blocked when P-10 is met
→When P-6 no longer met, trip is automatically reinstated.
→Can be manually unblocked when P-10 no longer met

Question 3

Intermediate Range Hi Flux Rx Trip

→What does it protect against?
→Setpoint?
→Coincidence?

Answer 3

Intermediate Range Hi Flux Rx Trip

→Startup Accident
→IR current ≈ 25% PR
→1/2 IR Detectors

Question 4

Intermediate Range Hi Flux Rx Trip

Notes/What does it do?

Answer 4

Intermediate Range Hi Flux Rx Trip

→Can be blocked manually when P-10 is met.
→When P-10 no longer met, trip is automatically reinstated.

Question 5

Power Range Hi Flux “Low Setpoint” Rx Trip

→What does it protect against?
→Setpoint?
→Coincidence?

Answer 5

Power Range Hi Flux “Low Setpoint” Rx Trip

→overpower condition, uncontrolled RCCA bank withdrawal
→≥25%
→2/4 PR detectors (alarm on 1/4)

Question 6

Power Range Hi Flux “Low Setpoint” Rx Trip

Notes/What does it do?

Answer 6

Power Range Hi Flux “Low Setpoint” Rx Trip

→Can be blocked manually when P-10 is met.
→When P-10 no longer met, trip is automatically reinstated.

Question 7

Power Range Hi Flux “Hi Setpoint” Rx Trip

→What does it protect against?
→Setpoint?
→Coincidence?

Answer 7

Power Range Hi Flux “Hi Setpoint” Rx Trip

→DNB
→109%
→2/4 PR Detectors (alarm on 1/4)

Question 8

Power Range Hi Flux “Hi Setpoint” Rx Trip

Notes/What does it do?

Answer 8

Power Range Hi Flux “Hi Setpoint” Rx Trip

→Cannot be blocked.

Question 9

Power Range Hi Positive Trip Rate Rx Trip

→What does it protect against?
→Setpoint?
→Coincidence?

Answer 9

Power Range Hi Positive Trip Rate Rx Trip

→rod ejection
→+5% w/time constant of 2 seconds
→2/4 Channels (alarm on 1/4)

“Five-two, peeeeewww!!!”

Question 10

Power Range Hi Positive Trip Rate Rx Trip

Notes/What does it do?

Answer 10

Power Range Hi Positive Trip Rate Rx Trip

→Must be manually reset at NIS cabinets
→Setpoint is variable based on rate of power increase (i.e. 2.5 % in 1 second will actuate trip, 5% increase in 2 seconds will actuate trip, 10% increase actuates immediately)

Question 11

Manual Rx Trip

→What does it protect against?
→Setpoint?
→Coincidence?

Answer 11

Manual Rx Trip

→Protects against - N/A
→Setpoint - N/A
→Coincidence - 1 of 2 handswitches

Question 12

Manual Rx Trip

Notes/What does it do?

Answer 12

Manual Rx Trip

→trip switches located on CB-07 and CB-10
→switch on CB-07 can be used to close Trip breakers

Question 13

RCP Undervoltage Rx Trip

→What does it protect against?
→Setpoint?
→Coincidence?

Answer 13

RCP Undervoltage Rx Trip

→DNB, anticipates loss of coolant flow
→4830 volts
→2 of 4 RCPs

Question 14

RCP Undervoltage Rx Trip

Notes/What does it do?

Answer 14

RCP Undervoltage Rx Trip

→P-7 must be met in order to trip.
→0.5 sec time delay

Question 15

RCP Underfrequency Rx Trip

→What does it protect against?
→Setpoint?
→Coincidence?

Answer 15

RCP Underfrequency Rx Trip

→DNB, anticipates loss of coolant flow
→57.2 Hz
→2 of 4 RCPs

Question 16

RCP Underfrequency Rx Trip

Notes/What does it do?

Answer 16

RCP Underfrequency Rx Trip

→P-7 must be met in order to trip.
→Also trips open all RCP breakers to extend coast down time.
→0.1 sec time delay

Question 17

Low Loop Flow Rx Trip

→What does it protect against?
→Setpoint?
→Coincidence?

Answer 17

Low Loop Flow Rx Trip

→DNB
→≤90% flow
→2/3 on 1 loop if P-8 (> 48%) is met OR 2/3 on 2 loops if P-7 is met (>10%) but not P-8 (>48%.

Question 18

Low Loop Flow Rx Trip

Notes/What does it do?

Answer 18

Low Loop Flow Rx Trip

→P-7 must be met in order to trip.
→Setpoint dependent upon Rx power, between P-7 (10%) and P-8 (48%) then requires 2 loops to be < 90% flow. If P-8 met (>48%) then only requires 1 loop to be < 90% flow.

Question 19

OT N-16 Rx Trip

→What does it protect against?
→Setpoint?
→Coincidence?

Answer 19

OT N-16 Rx Trip

→DNB
→115% ± penalties
→2/4 channels

Question 20

OT N-16 Rx Trip

Notes/What does it do?

Answer 20

OT N-16 Rx Trip

→If RCS press increases then setpoint increases and vice versa.
→If RCS temp increases then Setpoint decreases and vice versa.
→0.7 sec time delay.

Question 21

OP N-16 Rx Trip

→What does it protect against?
→Setpoint?
→Coincidence?

Answer 21

OP N-16 Rx Trip

→excessive kW/ft, mitigates consequences of steamline break
→112%
→2/4 channels

Question 22

OP N-16 Rx Trip

Notes/What does it do?

Answer 22

OP N-16 Rx Trip

→Backup to PR Hi Flux (Hi Setpoint) trip.
→Not sensitive to Rx vessel down comer temp changes as is PR NIs.

Question 23

PZR Low Pressure Rx Trip

→What does it protect against?
→Setpoint?
→Coincidence?

Answer 23

PZR Low Pressure Rx Trip

→DNB
→1880 psig, rate compensated
→2/4 channels

Question 24

PZR Low Pressure Rx Trip

Notes/What does it do?

Answer 24

PZR Low Pressure Rx Trip

→P-7 must be met in order to trip.
→Trip is automatically bypassed when P-7 no longer met.
→The faster pressure decreases, the higher above setpoint the Rx will trip.

Question 25

PZR Hi Pressure Rx Trip →What does it protect against? →Setpoint? →Coincidence?

Answer 25

PZR Hi Pressure Rx Trip →RCS overpressure →2385 psig →2/4 channels

Question 26

PZR Hi Pressure Rx Trip Notes/What does it do?

Answer 26

PZR Hi Pressure Rx Trip →N/A

Question 27

PZR Hi Level Rx Trip →What does it protect against? →Setpoint? →Coincidence?

Answer 27

PZR Hi Level Rx Trip →backup to high pressure trip; prevent sending water thru safeties →92% →2/3 channels

Question 28

PZR Hi Level Rx Trip Notes/What does it do?

Answer 28

PZR Hi Level Rx Trip →P-7 must be met in order to trip. →Trip is automatically bypassed when P-7 no longer met.

Question 29

S/G Lo-Lo Level Rx Trip →What does it protect against? →Setpoint? →Coincidence?

Answer 29

S/G Lo-Lo Level Rx Trip →loss of heat sink →U1 38%, U2 35.4% →2/4 channels on 1 S/G

Question 30

S/G Lo-Lo Level Rx Trip Notes/What does it do?

Answer 30

S/G Lo-Lo Level Rx Trip →2/4 channels on 1 SG will start MDAFWPs. →2/4 channels on 2 SGs will start TDAFWP. →1.0 sec time delay to allow for transients.

Question 31

Turbine Trip Rx Trip →What does it protect against? →Setpoint? →Coincidence?

Answer 31

Turbine Trip Rx Trip →limits transients on Rx, anticipatory trip →≤59 psig trip oil pressure OR all stop valves closed →2/3 pressure switches OR 4/4 stop valves closed

Question 32

Turbine Trip Rx Trip Notes/What does it do?

Answer 32

Turbine Trip Rx Trip →Trip is not active until P-9 is met. →Trip is automatically bypassed when P-9 no longer met.

Question 33

Safety Injection Rx Trip →What does it protect against? →Setpoint? →Coincidence?

Answer 33

Safety Injection Rx Trip →limits consequences of an accident →any SI signal causes Rx trip →N/A

Question 34

Safety Injection Rx Trip Notes/What does it do?

Answer 34

Safety Injection Rx Trip →Signal initiated thru SSPS via slave relays →if uPC1 lost, Train A will not actuate →if uPC2 lost, Train B will not actuate

Question 35

SSPS General Warning Rx Trip →What does it protect against? →Setpoint? →Coincidence?

Answer 35

SSPS General Warning Rx Trip →anticipatory loss of Rx protection →General Warning Alarm →2/2 trains of SSPS

Question 36

SSPS General Warning Rx Trip Notes/What does it do?

Answer 36

SSPS General Warning Rx Trip →General warning informs operator that SSPS is in a degraded condition.

Question 37

Cristian's mnemonic for the list of reactor trips

Answer 37

"Sip Mr. Loop's Teas, Sport" →each P has three Ps in a row →roll your Rs (two Rs in a row) S - Source Range Hi Flux I - Intermediate Range Hi Flux P - Power Range Hi Flux "Low Setpoint P - Power Range Hi Flux "Hi Setpoint" P - Power Range Hi Positive Rate M - Manual R - RCP Undervoltage R - RCP Underfrequency L - Low Loop Flow O - OT N-16 O - OP N-16 P - PZR Low Pressure P - PZR Hi Pressure P - PZR Hi Level 'S - S/G Lo-Lo Level T - Turbine Trip S - Safety Injection S - SSPS General Warning