Circulating Water (CW) Flashcards
What will block a CW pump start? How is this bypassed?
The associated loop condenser outlet valve closed will block CW pump start in that loop.
Can bypass with pushbutton on B07.
How will UV-11 respond to a loss of all running CW pumps in a loop?
UV-11 will auto close when there are no running pumps in a CW loop.
If taken to open then UV-11 will open regardless.
What are the starting interlocks associated with the CW pump discharge valves?
CW pump discharge valves:
* 1st pump start IN A LOOP Pump starts and its associated pump discharge goes to 44% open
* 2nd pump start IN A LOOP pump starts and disch valve** goes to 44%. waits for 3 min** and then goes to 100%, after 2nd pump discharge goes 100% then the 1st pump valve goes to 100%
* 1st pump stopped IN A LOOP (with 2 pumps running) Pump switch to stop, associated discharge valve goes to 8% open, the associated pump will trip, and discharge valve full closes. Discharge valve is interlocked closed for 2 min
* Discharge valve of the 2nd pump auto closes to 44% if the cross-tie valve is full open AND only 1 CW Pump is running in the other loop or cross-tie is not FULL open.
What is the interlock to open the CW Condenser outlet valves (CWN-HV-9/10)?
Pressure switches must indicate that the waterboxes are full.
What cools the CW pump bearing and motor lube oil coolers?
(TC) Turbine Cooling Water
What happens to the HI vibration trip of the CW tower fans on fan start?
It is bypassed for 30 seconds.
State what happens when the first CW pump in a loop is stopped.
What does this prevent?
On pump stop:
that pump disch valve starts to close.
At 8% open, the associated pump trips and the valve finishes closing.
This disch valve is interlocked closed for 2 min.
Following pump stop, the running pump discharge valve in the SAME loop will auto close to 44% if:
The cross tie valve is not full open OR
The cross tie valve is full open AND only 1 pump is running in the other loop.
Prevents runout of the running CW pump in the loop
Where can you emergency stop a Circulating Water Pump?
Control Room and locally at the pump breaker
