Component cooling Flashcards
Purpose of CC system:
- Heat removal from plant components during normal operation, plant cooldown and post accident.
- Intermediate heat removal system:
a. Removes heat from potentially radioactive components
b. Transfers heat to SX (Ultimate heat sink).
CC design
During NORMAL operation, the temperature of the CC HX outlet should not exceed 105F, based on max SX inlet temp of 100F.
During the INITIAL PHASE OF RHR COOLDOWN, the temperature may be permitted to increase to 120F for up to 3 hours.
The 120F CC design limit is based on ______________ limits.
Thermal barrier
3 pumps/ 2 HXs yields a CD rate of _____ with RHR on _____.
40F/hr; maximum
CC pump auto starts (3)
- SI
- UV on ESF bus (20 seconds)
- Discharge pressure <=85 psig (4 sec TD, blocked on emerg start of DG for 20 seconds)
The low discharge pressure auto start of CC pumps occurs at ______psig, has a ______seconds time delay and is blocked for ______ seconds after ____________.
<=85psig
4
20
EDG emergency start
U0 CC pp will only auto start if _________
A or B CS in PTL
U-0 pp control power fuses installed
U0 PP breaker racked into that bus
RSP C/S in _____ will/will not inhibit auto pump starts.
Local; will not
Normal temperatures, pressures and flow rates:
70-100F, min temp limit 60F for RCP thermal barriers
135-140 psig, min press 85# max press 150#
Flow rates:-4800 GPM at 130#
-7000 GPM runout
-500 GPM minimum
CC201A and CC202A open at_____
CC201B and CC202B open at _____
CC201A and CC201B auto close when level rises ______ above setpoints and following a _____time delay.
CC202A and CC202B close at ______
30%
22%
10% above setpoint and following 5 minute time delay
90%
CC17 auto _____ on a _______ signal.
closes; radiation
Pump trips:
- Low surge tank level 13%
- OC on phase A or C
- UV
- Ground over current
The U-0 CC pp will not auto trip on level of 13% if ______.
Control power fuses are removed from the associated CC01PA or CC01PB breakers.
LT670/LSL072 side of surge tank trips the _____ pumps at______. Also operates PW makeup valve CC-182 to maintain level _______.
LT676/LSL073 side of surge tank trips the _____ pumps at _____. Also operates WM makeup valve CC-183 to maintain level ________.
A/O CC; 13%; 42-55%
B/0 CC; 13%; 50-55%
With common CC HX aligned to Unit 1, ____ supplies U1 A and B safety loops and __________ safety loop. U2 supplies U2s ________only.
U1; U2 A train; B safety train loop only