P-Signals & C-Signals Flashcards
(20 cards)
P-4
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Reactor Trip (Protection Grade signal)
→ Setpoint: reactor trip breakers open
→ Coincidence: train associated trip breaker AND bypass breaker open or not connected
Notes / What does it do?
→Arms Steam Dump system to allow steam dump operation in the T-ave mode from Plant Trip Controller
→Activates Main Turbine trip
→Blocks auto re-actuation of SI after manually resetting SI
→Will generate a FWI signal IF T-avg is below Low T-ave setpoint of 564°F (does NOT trip MFPs)
→Seals in FWI signal due to SI or HI-HI S/G level (P-14)
Note: P-4 signals processed by SSPS
P-6
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Source Range Reactor Trip Block Permissive
→ Setpoint: >10^-10 amps
→ Coincidence: 1/2 IR
Notes / What does it do?
→Allows manual block of SR Hi Flux trip (2/2 block switches)
→Block switches also de-energize SR Hi Volts
→When <5x10^-11 amps on 2/2 channels then: SR Hi volts re-energized, SR trip and Flux Doubling protection re-instated (aforementioned occurs automatically)
P-7
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
At Power Permissive
→ Setpoint: none
→ Coincidence: P-10 or P-13 met
(2/4 Excore PR NIs >10% or 1/2 Turb Impulse Press >10%)
Notes / What does it do?
Following Rx trips re-instated with P-7 met:
→PZR Lo Pressure
→PZR Hi Level
→RCP Undervoltage
→RCP Underfrequency
→Low Flow in 2 RCS Loops
Above trips are blocked when P-7 no longer met
P-8
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
3 Loop Flow Permissive
→ Setpoint: >48%
→ Coincidence: 2/4 PR channels
Notes / What does it do?
→Allows for Rx trip when low flow condition is sensed on 2/3 channels on 1 RCS loop.
→Automatically blocked with 3/4 NIS channels <48%
“8 and 3 look almost alike”
P-9
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Turbine Trip Permissive
→ Setpoint: >50%
→ Coincidence: 2/4 PR channels
Notes / What does it do?
→When met, generates Rx Trip if Turbine Trip occurs
→Automatically blocked when <50% on 3/4 PR channels
P-10
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Nuclear At Power Permissive
→ Setpoint: >10%
→ Coincidence: 2/4 PR NI channels
Notes / What does it do?
When met it performs the following:
→Feeds P-7
→Automatically blocks SR Trip and de-energizes SR Hi Volts
→Allows blocking of IR Hi Flux Trip and C-1
→Allows blocking of PR Hi Flux Trip (Low setpoint)
→SR Hi Flux at Shutdown annunciator and CNTMT Evacuation alarm defeated
When 3/4 PR channels <10% the following are automatically re-instated:
→IR Trip
→C-1
→PR Trip (Low setpoint)
→Removes permissive to P-7
P-11
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
PZR SI Block Permissive
→ Setpoint: <1960 psig
→ Coincidence: 2/3 protection channels (doesn’t use channel 4)
Notes / What does it do?
When met allows manual blocking of:
→Low PZR Pressure SI
→Low Steam Line Pressure SI
(once blocked the High Negative Rate Steam Line Pressure Steam Line Isolation is armed)
Once PZR Pressure is >1960 psig on 2/3 channels, then:
→Low PZR Pressure SI armed
→Low Steam line Pressure armed
→Negative Steam Line Pressure High Rate is blocked and sends an OPEN signal to SI Accumulator isolation valves
P-12
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Lo-Lo T-ave Permissive
→ Setpoint: ≤553 deg F
→ Coincidence: 2/4 channels
Notes / What does it do?
→When met automatically closes all steam dump valves
→The 3 cooldown steam dump valves may be opened by using bypass switch
P-13
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Turbine At Power Permissive
→ Setpoint: turbine power > 10% (PT-505/506)
→ Coincidence: 1/2 turbine impulse pressure channels
Notes / What does it do?
→Feeds P-7 permissive
→Automatically removes signal to P-7 when no longer met
P-14
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Steam Generator Hi-Hi Level (Protection)
→ Setpoint: U1 84%, U2 81.5%
→ Coincidence: 2/3 detectors on any 1 SG
Note: control channels don’t count for the 2/3 detectors and are considered inoperable.
→Normal: Channel 1 for SGs 1&4, Channel 2 for SGs 2&3
→Alternate: opposite of normal - Channel 1 for SGs 2&3, Channel 2 for SGs 1&4
Notes / What does it do?
→Trips Main Turbine
→Trips Main Feed Pumps
→Generates Main Feedwater Isolation signal
Note: does NOT directly trip Rx; don’t fall for that distractor on an exam.
C-1
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Intermediate Range Rod Stop (prevent reaching IR & PR Hi flux trips)
→ Setpoint: IR amps ≈ 20% PR
→ Coincidence: 1/2 IR channels
Notes / What does it do?
→Stops outward rod motion in auto AND manual.
→Can be manually blocked when P-10 is met (2/2 switches)
→Automatically unblocked when P-10 no longer met
C-2
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Power Range Rod Stop (prevent reaching PR Hi Flux trip)
→ Setpoint: 103%
→Coincidence: 1/4 PR channels
Notes / What does it do?
→Stops outward rod motion in auto AND manual
→Can be bypassed at the NIS cabinets
→Loss of any PC bus will cause a C-2 because of required coincidence
C-3
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
OTN-16 Rod Stop & Turbine Runback
→ Setpoint: 112 ± penalties (3% below OTN-16 Rx Trip setpoint)
→ Coincidence: 2/4 N-16 channels
Notes / What does it do?
→Stops outward rod motion in auto AND manual.
→Generates Turbine runback (runback works as follows, on for 1.5 sec @ 200%/min then off for 28.5 sec, cycle continues until C-3 clears)
C-4
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
OPN-16 Rod Stop & Turbine Runback
→ Setpoint: 109% (3% below OPN-16 Rx Trip setpoint)
→ Coincidence: 2/4 N-16 channels
Notes / What does it do?
→Stops outward rod motion in auto AND manual.
→Generates Turbine runback (runback works as follows, on for 1.5 sec @ 200%/min then off for 28.5 sec, cycle continues until C-4 clears)
C-5
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Low Power Interlock
→ Setpoint: ≤ 15% turbine power
→ Coincidence: 1/1 from PT-505 or 506
Notes / What does it do?
→Based on which turbine 1st stage pressure transmitter is selected to input to rod control system.
→Stops outward rod motion in auto w/ power <15%
C-7
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Loss of Load
→ Setpoint: 10% with time constant of 120 sec
→ Coincidence: based on turbine power load reduction
Notes / What does it do?
→Allows dump valves to open in T-ave mode following load rejection. (Arms the Steam Dumps)
→Setpoint is variable based on rate of load rejection i.e. 5%/min will actuate C-7 in 1 min, 10% step change will actuate C-7 immediately
→Must be manually reset by taking the Steam Dump Mode Selector Switch to “Reset”
C-9
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Condenser Interlock
→ Setpoint: >12.3” Hg vacuum (2/2; uPC2)
→ Coincidence: Condenser vacuum plus 2/4 Circ Water Pump breakers closed
Notes / What does it do?
→Allows steam dumps to open when C-9 is met
“C-9, condenser’s fine”
C-11
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Control Bank D Rod Withdrawal Limit
→ Setpoint: 223 steps
→ Coincidence: N/A
Notes / What does it do?
→Stops outward rod motion in auto only
C-16
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
Stop Turbine Loading (prevent excessive T-ave droop)
→ Setpoint: 553°F auctioneered low T-ave OR auctioneered low T-ave < T-ref by 20° F
→ Coincidence: N/A
Notes / What does it do?
→Stops turbine loading when met
C-20
→What is it?
→Setpoint
→Coincidence
→Notes / What does it do?
AMSAC
→ Setpoint: >40% turbine power, no TD
→ Coincidence: 2/2 from PT-505/506
Notes / What does it do?
→Enables AMSAC actuation circuit
→505 or 506 <40% Blocks AMSAC after 260 sec. TDDO, this actually turns on PCIP light
