RCS Flashcards
When RCS > what temperature, is
a continuous MU bypass flow of
how many gpm to B HPI?
> 250F, flow of 3 gpm
Be at least what delta k/k
shutdown if the most conservative
WR cold leg temp is less than
what?
1% delta k/k, <525F
Do NOT open pzr spray valve
unless delta T between RCS and
pzr is less than or equal to what
temperature?
250F
Maintain RCS dissolved gas <
what setpoint H2O to prevent
accumulation in CRDM?
<100 cc/kg H2O
Pzr H/U and C/D rate?
100 F/HR
Maintain min pzr spray bypass
flow of what gpm when RCS >
what temperature?
.75 gpm and RCS >200F
When venting pzr to RCDT at low
pressure, avoid large pressure or
level transients by using what?
Small taps on RC-V-28 OPEN
pushbutton
Tech specs
Leakage: basis is “leak before
break” strategy
When Rx critical > what percent power,
how many RCS leak detection systems
of different operating principles shall be
in operation with X of X sensitive to
radioactivity. Systems may be OOS up
to how many hours provided RB atm
samples how many hours?
> 2%
2 RC leak detection systems
1 of 2 sensitive to radioactivity
OOS up to 72 hours
RB atm sampled 8 hours
Normal Makeup flow path
RC-P-1B discharge via B HPI/MU-
V-17
Letdown flow path
RC-P-1C suction line via MU-V-
1A/B
Pressurizer Surge line
A Hot Leg
Pressurizer spray line
RC-P-1A discharge via RC-V-1/3
Drop Line
B hot leg via DH-V-1/2/3
HPI
RCP discharge lines via MU-V-
16A/B/C/D
LPI
CF Nozzles via DH-V-4A/B
Once through steam generators (RC-
H-1A/B)
EFW nozzles: how many nozzles per
OTSG, sprays where to promote what
and reduce thermal stress on what?
7 nozzles per OTSG, sprays on
tubes to promote natural circulation,
reduce thermal stresses on the
lower tube sheet
Tube to shell DT: tensile and
compressive temperatures
-70F (tensile) or +60F
(compressive)
RCDT (WDL-T-3): Auto signals does
what?
IC-V-20 opens w/ WDL-P-8 starts
(110F, trips @ 105F if IC-V-4 is
OPEN).
RCDT relief valve set point
40 psig
RCDT rupture disc setpoint
55 psig
OTSG milestones High to Low (just
percentages)
97.5% HSPS FW isolation (2/4)
90% ICS HLL (auto control)
88% HI OTSG level alarms
75-85% Loss of 25F SCM
50% Loss of 4 RCPs HSPS Auto
contro
OTSG milestones High to low (just inches
of vacuum)
25” S/U LLLs (AUTO), HSPS EFW
control (Auto)
- Loss of both FWPs, 10” OTSG,
4#RB
20” S/U OTSG low level alarm
10” S/U HSPS low OTSG lvl EFW
AUTO start
Pressurizer RC-T-2 capacity
12 gal/inch
Pressurizer RC-T-2 Heaters, how many
groups and how many heaters in each of
how many banks?
13 groups, 9 heaters in 5 banks
Pressurizer Heater Banks, which ones
and how are they controlled?
Banks 1,2,3 are SCR Controlled
(variable heat demand)
Banks 4 and 5 are bistable
Controlled (on/off)
Pressurizer heater control table,
setpoints
Find table
Where does MU come in?
MU from downstream RCP B
between pump and RX
Where does HPI come in?
Between all RCP and RX
Where is let down go?
Suction side of RCP C
Pressurizer Power Supply:
1E and 1F 480V switchgear, 1A and
1B PZR Heater MCC’s
Pressurizer emergency power
Group 8 or Group 9, 1P or 1S 480V
switchgear
Pressurizer interlocks
All heaters De-energize at what
pressurizer level (what level does it
uncover) EXCEPT when powered
from where?
80” pressurizer level (63.5”
uncovered) EXCEPT when
powered from 1P/1S ES switchgear
Can’t energize heaters < what pzr
level (interlock bypass key where?)
ON a loss of what you would need to
defeat the interlock that actuates.
<80” (interlock bypass key in
ICS/NNI cabinet) ON a loss of ICS
AUTO power, interlock actuates
and you need to defeat this
Which pzr groups trips on Es?
Groups 8 and 9
Which group has 69 bypass on 1s
480v to prevent tripped on ES when
in emergency?
Group 9
Pzr level control
Nominal level ensures pzr does not
what post trip to prevent what?
Ensures pzr does NOT empty post
trip to prevent loss of SCM
Pzr tech specs
Pzr HU and CD rates shall NOT
exceed what F/hr?
100F/HR
RX shall be maintained subcritical
>what percent deltaK/k until pzr
level what to what inches or else be
in HSD w/ CRD breakers Open in
how many hours and CSD in how
many hours?
> 1% deltak/k until pzr level 80-385”
or else
Be in HSD w/ CRD breakers OPEN
in 6 hours and CSD in 30 hours
Pressurizer spray power supply
1A ES MCC
Pressurizer spray
Auto signals:
Close at 2155#, OPEN at 2205#
RCS to 40%@ 140 gpm
Manual Control: RC-v-1 can be
OPENED in JOG up to 100% (190
gpm). Must place switch back to
what position, will only close at what
pressure in auto?
Auto
2155# in Auto
Where is HPI come in at?
RCP discharge side on all legs
RCITS
HOT leg level: RCPs off
Reactor vessel level: RCPs off
% void fraction: RCP’s operating
RCS Drain Down Level: RCS
drained down
MU-V-17 normal makeup
220” by the MU system using
normal MU valve, MU-V-17 in
automatic and letdown flow
Dry OTSG
<200 psig below saturation
pressure
And less than 6”
If you have a void in the hotleg can
you have natural circulation?
No you can’t establish natural circ
with a void in the hot leg
Can’t start a 4th RCP unless you’re
above what temperature
407 F
Why do we need to compensate pzr
level temperature?
It’s a differential pressure detector
How many pressure detectors in A
hot leg? What pressure bands and
used for what?
5, two narrow ranges/rosemound detectors: 1700-2500
psig
For RPS, PORV, heaters and spray
2 wide ranges/bourdon tubes
0-2500 psig
For ESAS, PORV, DH interlocks
One wide range rosemount detector
Safety grade (post accident)
0-3000 psig
Used for Tsat memters, DSS trip
What type of flow tube in each hot
leg? Connected to how many
differential pressure instruments?
Gentile flow tube
Connected to 4 differential pressure
instruments
Pressurizer spray
Purpose, if spray fails OPEN, plant
may remain online by doing what?
Condenses steam to reduce pressure,
RC-P-1A discharge normal source.
Kept online by closes RC-V-3 (block
valve) which is the pressurizer spray
isolation valve
Power supply to spray isolation
valve (RC-V-3)
1B ES MCC
Pressurizer spray isolation valve
(Rc-v-3)
Purpose
Isolations (full open/close) if rc-v-1 fails
but eliminates bypass flow
Pressurizer spray isolation bypass
(rc-v-24)
Purpose
Maintains .75-1.5 gpm flow around
spray valve RC-V-1 to prevent
thermal shock to the spray valve and
nozzle and continuous outflow from pzr
to equalize boron concentration
“mixing” (within 50 ppm)
Pressurizer Aux Spray (RC-V-4)
Type of valve, power supply,
purpose
MOV
1C ES valves MCC
Provides pzr spray at low pressures
during cooldown from discharge of
decay heat pumps
High Pressure relief
PORV (RC-RV-2)
Type of valve?
Power supply?
MOV/SOV
1C 250V DC
PORV
Auto signals
OPEN at RCS #2450, CLOSE at RCS
#2400
PORV Tech specs
LTOP porv pressure when RCS is
less than what temperature? How
long to restore or verify pzr level is
less than or equal to what?
<313F is 592#
Restore in 8 hours or verify pzr level
≤100”
If LTOP not in effect, PORV min
setpoint is what pressure? Restore
in how much time OR shut what OR
shut and remove power from PORV
OR be in what in how much time
and CSD in how much time?
PORV min setpoint is #2425
Restore in 8 hours OR
Close block valve OR
Close and remove power form PORV
OR
Be in hotstandby in 6 hours and CSD
in 30 hours
When RCS is less than what temp,
PORV shall NOT be taken OOS or
isolated unless HPI pumps racked
OUT, MUV-what Closed w/ bkrs to
what position and MU-V-what
Closed/open or RX head off.
<313F
MUV-16’s
Breakers open (MUV-16)
MUV 217 closed
PORV clock valve shall be
OPERABLE during hsby, s/u and
power ops. If INOPERABLE, restore
in how much time or close what and
remove power OR be in hsby in how
much time and CSD in how much
time?
Restore in 1 hour OR
Close PORV (verify closed) And
Remove power OR
Be in hsby in 6 hours or CSD in 30
hours.
PORV tech spec
Design basis
Prevents overpressure by eliminating
high pressure sources or assuring RCS
open to atm. Block valve required to
provide isolation of PORV to control
potential RCS depressurization
PORV
NDTT Switch
Two position switch located on PC which
changes PORV setpoint for LTOP concerns
when RCS is less than what temp? in off
setpoint is what? In auto position the OPEN
setpoint to what pressure and Close at what
pressure when Tcold is < what?
RCS <313F
In OFF setpoint is #2450
In Auto open is #592 and close at #542
when Tcold <313F
PORV
Other
NDTT switch kept OFF because a single failure
of WR Tcold instrument LOW would cause the
PORV to OPEN. Per 1101-11, we place NDTT
switch to what position after RCS< what temp
and prior to RCS < what temp?
Place NDTT switch in Auto after
RCS<565F and prior to RCS <313F
PORV isolation valve (RC-V-2)
Type of valve and Power supply
MOV, a D-ring top of pzr
1C ES valves MCC
Most important pzr level mile stone
370”
Enter AOP-43 loss of pressurizer and
trip RX
Porv acoustic monitors (2 channels)
Located on valve body, indicates if PORV is
OPEN, alarm annunciator at how many G’s (%)
0.3G’s (5%)
Tail pipe (delta P)(3 channels)
1 for PORV, 2 for code safeties
Indication on CC, how many inches delat p
alarm setpoint (%)
20” delta P alarm setpoint (5%)
Tail Pipe delta P (3 channels)
T.S. 3.5.5 accident monitoring requires how
many channels, how many minimum?
2 channels with 1 minimum
