P & C Signals, Trips & SI's Flashcards
P-4
coincidence
inputs
Rx trip and associated bypass breaker open
RTA + BYA (P-4a) 2/2 per train
RTB + BYB (P-4b) 2/2 per train
- trips turbine
- closes FRV & bypass w/ Tave < 554 F
- seal in SI reset
- steam dumps to Rx trip mode (B)
- blocks stm dumps 3/4, arms 1/2 (A)
P-6
coincidence
inputs
IR permissive > 10-10 ica
1/2
- permits manual blocking of SR trip (105 cps)
- allows de-energizing of SR Ni’s
(provides one decade of overlap between SR and IR)
P-7
coincidence
inputs
P-10 met ( > 10% PR)
or
P-13 met ( >10% Pimp)
1/2
enables trips:
- Pzr low pressure
- Pzr high level
- RCP bkr open
- RCP bus UF or UV
- RCS loop low flow
(should not operate above 10% w/ these conditions)
P-8
coincidence
inputs
PR > 35%
2/4
Changes loss flow Trip 2/4 loops -> 1/4 loops
DNB protection
P-9
coincidence
inputs
PR > 50%
2/4
Activates Rx Trip on every turbine Trip > 50%
protects against major LR
P-10
coincidence
inputs
PR > 10%
2/4
Allows blocking:
- PR flux Trip (low) 25%
- IR flux Trip (hi) 25% equivalent
- IR Rod stop 20% (C-1)
Blocks:
- Subcooling monitor alarm
Inputs:
- P-7 (low power permissive)
P-11
coincidence
inputs
Pzr Press >/= 1915 psig
2/3
below:
- allows blocking of Low Ppzr SI
- allows blocking of Low Pstmln SI and SLI
- allows enabling of Hi rate SLI
above:
- enables Low PPzr SI
- enables Low Pstmln SI and SLI
- disables Hi rate SLI
- sends open signal to Accum isolation valves
P-12
coincidence
inputs
Tave < 543 F
2/4
Blocks all steam dump valves
(protects against uncontrolled cooldown)
(Group 1 is bypassable)
P-13
coincidence
inputs
Pimp > 10% (turbine power equivalent)
1/2
Provides input to P-7
P-14
coincidence
inputs
L S/G > 90% NR
2/3 sensors 1/4 S/G
- trips Main turbine
- trips FWP turbines
- closes FWI valves
- closes FW control and bypass valves
C-1
coincidence
inputs
IR rod stop > 20% (current equiv)
1/2
stops outward rod motion (auto and manual)
can be blocked at P-10
C-2
coincidence
inputs
PR Rod stop @ 103%
1/4
Blocks Auto & Manual outward Rod motion
Can be bypassed for testing or failed channel
C-3
coincidnence
inputs
OTAT Rod stop and runback
1% below trip setpoint
2/4
blocks auto and manual rod withdrawl
runback = 10% / min
(2400 MW/ min for 1.5 sec…..wait 28.5 sec)
(target is 203 MW, runback clears when cond clears)
C-4
coincidnence
inputs
OPAT Rod stop and runback
1% below trip setpoint
2/4
blocks auto and manual rod withdrawl
runback = 10% / min
(2400 MW/ min for 1.5 sec…..wait 28.5 sec)
(target is 203 MW, runback clears when cond clears)
C-5
coincidnence
inputs
Turbine low power < 15 % Pimp (PT-505)
1/1
Stops auto outward rod motion
C-7A
coincidnence
inputs
10% loss of load/ 140 sec
Pimp (PT-505a, 506a, PT-8)(MSS)
arms group 1 and 2 steam dumps (40%’s)
C-7B
coincidnence
inputs
50% loss of load / 140 sec
Pimp (PT-505a, 506a, PT-8)(MSS)
arms group 3 and 4 steam dumps (35%’s and 10%’s)
C-9
coincidnence
inputs
condensor available
Vacuum > 20” Hg + CWP running (bkr closed)
2/2 (Pcond) + bkr
permissive for steam dump groups 1 and 2 (40%’s)
C-11
coincidnence
inputs
Control Bank D Rod stop
CB D > 220 steps
stops automatic outward rod motion
C-20
coincidnence
inputs
PT-505/ 506 > 40% Core thermal power (equiv.)
2/2
Arms AMSAC
SR hi flux trip
coincidence
interlock
purpose
> 105 cps
1/2
blockable > P-6, when blocked SR de-energizes
S/U rod withdrawl accident
IR hi flux trip
coincidence
interlock
purpose
> 25% (current equiv)
1/2
blockable > P-10
S/U rod withdrawl accident
PR hi flux Trip (low)
coincidence
purpose
interlock
PR > 25%, trips Rx
2/4
Startup accident
Can be blocked > P-10 (2/2 switches)
PR hi flux Trip (hi)
coincidence
interlock
purpose
PR > 109%
2/4
Unblockable
Overpower (kw/ft), positive reactivity excursion
Hi flux rate Trip
coincidence
interlock
purpose
PR >/= +5% / 2 sec
2/4
seals in, must be reset @ Ni cabinet
ejected rod
OT delta T trip
coincidence
interlock
purpose
> 120% +/- penalties (bonus/penalties)
2/4
none
DNBR > 1.17
OP delta T trip
coincidence
parameter change setpoint
purpose
> 107.2% - penalties
2/4
Tave
kw/ ft
Loop low flow trip
coincidence
interlock
purpose
< 90%
2/3 sensors 1/4 loops (> P-8)
2/3 sensors 2/4 loops (< P-8)
< P-7 trip deactivated (10%)
P-8 changes coincidence (35%)
DNBR > 1.17
(< P-8, 1 low flow and 1 bkr open will initiate Rx trip)
RCP Bkr open trip
coincidence
interlock
purpose
bkr open
2/4
trip deactivated < P-7 (10%)
DNBR > 1.17
(< P-8, 1 low flow and 1 bkr open will initiate Rx trip)
RCP Bus UV trip
coincidence
interlock
purpose
8050 volts
1/2 sensors, 2/2 Buses (12kv D, E)
trip deactivated < P-7 (10%)
DNBR >1.17
RCP Bus UF
coincidence
interlock
purpose
54 Hz
2/3 sensors, 1/2 busses (12kv D, E)
trip deactivated < P-7 (10%), also trips RCP’s
DNBR > 1.17
Low Pressure Trip
Coincidence
interlock
purpose
Ppzr < 1950 psig (rate sensitive)
2/4
trip deactivated < P-7 (10%)
DNBR limit
High Pressure trip
coincidence
interlock
purpose
Ppzr > 2385 psig
2/4
none
RCS integrity
Hi Lpzr Rx trip
coincidence
interlock
purpose
Lpzr > 90%
2/3
trip deactivated < P-7 (10%)
B/U to Hi Ppzr/ prevent water out safties/ RCS integrity
L S/G low-low
coincidence
interlock
purpose
L S/G < 15%
2/3 sensors, 1/4 loops
delay time to trip: (Pwr < 50%, varies with delta T)
0% time delay ~ 500 sec
50% time delay ~ 30 sec
loss of heat sink
Turbine trip - Rx trip
coincidence
interlock
purpose
Low PAST < 50psig OR SV closed
AST 2/3 OR SV 4/4
trip deactivated < P-9 (50%)
limit temp/ Press transients in RCS
Manual Rx trip
coincidence
interlock
purpose
switch
1/2
none
operator judgement
SI Rx trip
coincidence
interlock
purpose
SI
any “S” signal
none
limits consequence of accident
Seismic Rx trip
coincidence
interlock
purpose
0.30 g
2/3 sensors in same direction (x, y, z)
none
Seismic B/U trip
SSPS General Warning Rx trip
coincidence
interlock
purpose
Train A & B SSPS simultanious GW
2/2 (1 train A + 1 train B)
none
Trip Rx if failure of protection system
Manual SI
coincidence
interlock
purpose
switch
1/2
none
operator judgement
CNMT Hi Press SI
coincidence
interlock
purpose
PCNMT > 3 psig
2/3
none
Hi energy line break inside CNMT
Low Ppzr SI
coincidence
interlock
purpose
Ppzr < 1850 psig
2/4
blockable < P-11 (auto unblock > P-11, (1915 psig))
LOCA
Low Pstm line SI
coincidence
interlock
purpose
Pstm line < 600 psig (lead-lag)
2/3 sensors, 1/4 loops
also actuates SLI, blockable < P-11 (1915 psig), when blocked actuates hi rate SLI
Steam line break