Circ Water

Question 1

Cooling tower pump normal indication

Answer 1

800 amps @ 40-45 psi discharge pressure

Question 2

Cooling tower pump power supplies

Answer 2

P-39A - F bus

P-39B - G bus

Question 3

Cooling tower pump start permissives

Answer 3

Condenser inlet waterbox full
No standing pump trips
Emergency stop button not pushed
Lubrication water >8 gpm
Waterbox inlet valve closed
Pump discharge valve closed

Question 4

What happens when C/T pump control switch is taken to start

Answer 4

Condenser inlet starts to open
Pump starts when condenser inlet is 33% open
Pump discharge valve starts to open to a preset throttle position (approximately 43%)

Question 5

What happens when C/T pump control switch is taken to stop

Answer 5

Pump discharge valve starts to close
Pump trips when discharge valve gets to 33% closed
Pump discharge valve fully closes

Question 6

What happens when C/T pump emergency stop push button is pushed

Answer 6

Immediately trips pump
Pump discharge valve closes fully
Control Room alarm

Question 7

C/T pump seal and cooling water supply

Answer 7

Normally from filtered service water

Self sealing if filtered service water is lost

Question 8

C/T pump seal/cooling water alarm

Answer 8

18 gpm

Question 9

C/T pump trips

Answer 9

Differential current
Bus undervoltage
Ground current
Overcurrent

Question 10

C/T pump discharge valves MO-5305/5306 functions

Answer 10

Control C/T basin level
Interlocks to open/close on pump start/stop
Won’t auto close if pump is tripped locally from the breaker

Question 11

Waterbox inlet valves MO-5301/5302 interlock

Answer 11

Open on C/T pump start

Question 12

Steps to take if waterbox inlet valve leakage is present

Answer 12

Operate the valve to flush the seat
Attempt to seat the valve
Drain the C/T

Question 13

Dilution water pump power supplies

Answer 13

P-40A - C bus

P-40B - E bus

Question 14

Dilution water pumps capacity

Answer 14

40,000 gpm

Question 15

Dilution water pump trips

Answer 15

overcurrent
undervoltage
SIS (load shed)

Question 16

Interlock associated with radwaste discharge and dilution water pumps

Answer 16

Radwaste discharge CV-1054 won’t open unless a dilution water pump is running

Question 17

Dilution water pump discharge pressure limitation

Answer 17

Less than 14 psi to prevent flow vibrations

Question 18

Dilution water pump discharge to mixing basin MO-5311/5312 function

Answer 18

Used during pump starts

Only 1 open at a time

Question 19

Dilution water pump discharge valves MO-5313/5314 function

Answer 19

Open or close, no throttling
60 second stroke time
Thermal overload has 116 second time delay to allow valve to fully stroke in an overload condition

Question 20

C/T fill MO-3515/5316

Answer 20

60 second stroke time

Thermal overload has 116 second time delay to allow valve to fully stroke in an overload condition

Question 21

C/T fan trips

Answer 21

Turbine trip
High vibration
Overload

Question 22

C/T fan controls

Answer 22

Controls will only start 1 fan on each LCC at a time
Individual - select which fan(s) are started/stopped. Push start/stop button to start/stop selected fans
Master - start/stop all fans
Fans will not automatically trip on a turbine trip if master start sequence is in progress

Question 23

C/T fan control Init/reset function

Answer 23

Warm reboot that takes < 2 minutes
Used to:
Clear PPC alarms
Lamp test
Re-establish communications with the towers

Lose indications of C/T bypass valves and level indication
Will not reposition any components

Question 24

C/T bypass valves MO-5340/5341 function

Answer 24

Routes C/T pump discharge from over the top to the bottom of the tower

Question 25

C/T blowdown valves MO-5326A/B function

Answer 25

Lower C/T level by routing water from the C/T to the mixing basin
CR alarm if blowdown flow exceeds 43,000 gpm from either tower

Question 26

What is the Circ Water System interrelationship with the Pressurizer level control program?

Answer 26

P-40A, Dilution Water Pump, breaker on “C” Bus can provide an alternate source of power to the Pressurizer Heaters. Breaker will trip on Pressurizer low-low level of 36%