Control interlocks

Question 1

C-1 IR high flux rod stop

Answer 1

Setpoint and Coincidence
1 of 2 IR 20% power w/ Hi IR flux trip unblocked
2 of 2 IR <20% to clear

Function
1. Stops outward rod movement in auto and manual. Blockable above P-10

Question 2

C-2 PR flux high rod stop

Answer 2

Setpoint and Coincidence
1 of 4 PR >103%
Function
1. Stops outward rods in auto and manual. Bypassable at NIS panel.

Question 3

C-3 OT delta T rod stop and turbine runback

Answer 3

Setpoint and Coincidence
2 of 4 delta T ch w/i 3% of OT delta T trip setpoint
3 of 4 >3% from setpoint stops runback

Function:

1. Stops auto and manual outward rod movement
2. Initiates turbine runback

Question 4

C-4 OP delta T rod stop and turbine runback

Answer 4

Setpoint and Coincidence
2 of 4 delta T ch w/i 3% of OP delta T trip setpoint
3 of 4 >3% from setpoint stops runback

Function

1. Stops outward rod movement in auto and manual
2. Initiates turbine runback

Question 5

C-5 Turbine low power

Answer 5

Setpoint and Coincidence
Validated Pimp<15% (Median PT 505, 506, median DEH Pimp)

Function
1. Stops outward rod movement in auto

Question 6

C-7 Loss of turbine load

Answer 6

Setpoint and Coincidence
10% decrease w/i 120 seconds on 2 of 3 P imp. 505, 506, median DEH Pimp

Function
1. Arms steam dumps in Tave mode

Question 7

C-8 Turbine trip

Answer 7

Setpoint and coincidence
2 of 3 EH pressure <1000#
or
All 4 turbine TVs closed

Function
1. Generates Reactor trip >P-8

Question 8

C-9 Condenser not available

Answer 8

Setpoint and coincidence
1 of 3 CW pump breakers closed -and-
1C exhaust hood less than 7.0” HgA
(This coincidence clears C-9)

Function
1. Blocks normal steam dump ops. Cannot be bypassed.

Question 9

C-11 CBD withdrawal limit

Answer 9

Setpoint and coincidence
CBD >= 223 steps (from Group 1 step counters) (Resets at 221 steps)

Function
1. Stops outward rod movement in auto.

Question 10

C-16 Turbine stop loading

Answer 10

Setpoint and coincidence

Validated (2nd lowest) Tave <553F -OR- Tave

Question 11

C-20 AMS perm

Answer 11

Setpoints and coincidences
2 of 2 P-imp ch >30%

Function
1. Arms AMS