Permissives

Question 1

P-4

Answer 1

Rx Trip Brkrs & Rx Trip Bypass Bkrs

2/2
2/2

Turbine Trip
Allows FWI on Low Tave (<574)
Allows Block and Reset of SI
Closes SG Blowdown if SR Flux Trip is Blocked

Question 2

P-6

Answer 2

SR Trip Block Permissive
IR NIS > 1e-10 amps

1/2 increasing
2/2 decreasing

Blocks Rx Trip: (Auto Unblock)
SR High Flux Trip

Question 3

P-7

Answer 3

At-Power Trip Permissive

Input from (P-10) or (P-13)

Allows Rx Trip:
Pzr Low Pressure Trip
Pzr High Level Trip
RCS Low Flow Trip
RCP UV/UF Trips

Question 4

P-8

Answer 4

Single Loop Loss of Flow Permissive PR NIS
< 40%
2/4 increasing
3/4 decreasing

Blocks Rx Trip:
RCS Low Flow in any single loop

Question 5

P-9

Answer 5

Turbine Trip to Rx Trip

PR NIS > 50%

2/4 increasing
3/4 decreasing

Allows Rx Trip:
Turbine Trip (C-8)

Question 6

P-10

Answer 6

PR Low Flux Trip Block Permissive
PR NIS > 10%

2/4 increasing
3/4 decreasing

Allows Block of IR High Flux Rod Stop (C-1)

Allows Block of PR Flux (Low SP) Trip

Backup to (P-6) – Removes SR Power

Input to (P-7)

Question 7

P-11

Answer 7

Low Pressure SI/SLI Block Permissive
Pzr Pressure < 1985 psig

1/3 increasing (Reset)
2/3 decreasing

Allows Blocks:
Pzr Low Pressure SI
SG Low Pressure SI

Allows closure of SI Accumulator Outlet Valves
On Reset (Provides Open Signal to SI Accum Valves)

Question 8

P-12

Answer 8

Low Tave Steam Dump Permissive

Tave < 563 F

2/4

Blocks Steam Dump Operations
(3 cooldown valves can be bypasses)
Vents air from Steam Dump Operators

Question 9

P-13

Answer 9

Turbine At-Power Trip Permissive

Impulse/InletPressure > 10%

1/2

Input to (P-7)

Question 10

P-14

Answer 10

SG Hi Level Trip

SG Level > 87.5%
2/4 in 1/4 SG

Trips Main Turbine
Trips SGFP Turbines
Trips SUFP
Feedwater Isolation
(P-4)

Question 11

P-16

Answer 11

Rx Trip to Turbine Trip

From–>(P-4 true) OR SSPS

Trips Main Turbine