SGWLC

Question 1

Discuss SGWLC Level lag

Answer 1

Level deviations have a 5 second lag to minimizes the effects of shrink and swell

Question 2

Discuss how the SGWLC flow controller develops a signal

Answer 2

Feed Flow develops and error signal
and/or
Level develops an error signal
SGWLC output = Feed error plus Level error

Question 3

Discuss Feed pump speed Control

Answer 3

DP is sensed from PT-507 and PT-508.
Programmed DP is sensed from all 4 SG steam flow (selected channel for SGWLC)
0-20%:80#
20-1005: 135#

Question 4

State FWI signals

Answer 4

P-14: SG Hi-Hi Level (90.8% 2/4 in any SG)
P-4 with Low Tave (557F 2/4)
Any SI signal

Question 5

Discuss train specific actions for FWI signal

Answer 5

A train: SUFP, A MFP

B train: B MFP

Question 6

State FWI auto actions

Answer 6

FRVs, FRV bypasses, FW Isolation Valves all close
MFPs trips (train specific)
Turbine trips (when caused by P-14 or SI)
SUFP blocked (A train P-14 or SI)

Question 7

State how to reset FWI

Answer 7

FWI reset switches on MCB (P-4 only)

Cycle Reactor trip breakers (SI or P-14)

Question 8

State what must happen if Containment Integrity is lost (T.S. 3.6.1.1) modes 1-4

Answer 8

Without primary CONTAINMENT INTEGRITY, restore CONTAINMENT INTEGRITY within
1 hour or be in at least HOT STANDBY within the next 6 hours and in COLD SHUTDOWN
within the following 30 hours.

Question 9

State what happens when the Controlling Level Channel fails high

Answer 9

FRV closes and Rx trips on 2/4 SG level Lo-Lo (20%)

Question 10

State what happens when the Controlling Level Channel fails low

Answer 10

FRV opens
P-14 FWI and turbine trip (RX trip of >P-9)
- 2/4 SG Hi-Hi 90.8%

Question 11

State what happens when the Controlling Feed Flow Channel fails high

Answer 11

FRV closes on error signal

Final SG level 42-44%

Question 12

State what happens when the Controlling Feed Flow Channel fails low

Answer 12

FRV opens due to error signal

SG level will be >80%, possible P-14 due to overshoot and turbine trip

Question 13

State what happens when Steam Flow Channel fails high

Answer 13

FRV opens due to flow error,
This will be balanced by level error
FRV closes back to original position

Question 14

State what happens when the Steam Flow Channel fails low

Answer 14

FRV closes due to error

Rx will trip on Lo-Lo SG Level (2/4 @20%)

Question 15

State what happens when PT-508 fails high or PT-507 fails low (max DP)

Answer 15

MFPs slow down to minimum (3700 RPM)

RX trips on SG level Lo-Lo (2/4 @ 20%)

Question 16

State what happens when PT-508 fails low or PT-507 fails high (min DP)

Answer 16

FRV close due to flow error and then level error
Final Level 50%
FW pressure high alarm