Crew is preparing to start a second Main Condensate pump in preparation for starting a main feedwater pump. Initial conditions are:
“A” CNM pump running
“B” and “C” CNM pumps in AUTO-AFTER-STOP
What action is the BOP operator required to take with the “B” CNM pump control switch at MB6 to start the pump?
Take switch to START. Hold in START until motor current indicates pump is operating. Release switch
Plant at 100%. HOTWELL SODIUM HI annunciator received.
What is the most likely source of the sodium; and what is the major concern with sodium in the hotwell?
Likely source is main circulating water system. Concern is corrosion in SG U-tubes
Plant is 100%.
Which pumps do NOT provide NPSH to the main feedwater pumps?
seal water booster pumps
Plant efficiency is increased by preheating of the secondary water supplied to the steam generators.
Which of the following items associated with the main condensate system performs this preheating function?
feed water heaters
BOP observes the condenser desuperheating spray valve is open. What condition could be the cause of this?
load rejection in progress
HOTWELL LEVEL HI/LO comes in
COND PP AUTO TRIP/OVERCURRENT comes in
What caused the operating main condensate pump to trip?
low hot well level of <5” above bottom
The inlet isolation valve to the feed system long recycle valve is normally shut to prevent what?
over pressurization of the long recycle piping
What condition would result in damage to the TDMFP seals?
temp of the condensate pump discharge exceeds 150F
What will auto start a standby condensate pump?
the breaker of a condensate pump trips OPEN
What percentage of the total condensate flow supplied to the suction of the main feed pumps is supplied from the two operating main condensate pumps?
63%
A load rejection occurs. What signal causes the desuperheating spray valve to auto open?
auto opens when the steam dump valve arms
What is the designed seal water header pressure from CNM-PCV34/106?
20-25 psig
A SGTR occurred. What are the three methods to be used for the clean up operation?
breaking main condenser vacuum and discharging contents of the hotwell via TK-10 or TK-11
pumping the hotwell to a temporary waste processing unit
place condensate system on SHORT RECYCLE with demins in service for activity removal
When is a second main condensate pump required to be operating?
when a main feed pump is operating
One of the main condensate pumps trip
Standby pump does not start
Main feed pump suction and discharge pressures are decreasing
What effect will this have on the main feed water system?
all main feed pumps will trip after time delay on low feed suction pressure. Result in LO-LO SG level reactor trip
What is the purpose of the double tube sheet construction in the main condenser waterboxes?
seal water supplies between the tube sheets is at a higher pressure than circ water, leaks will be from seal water to circ
COND DEMIN DP HI comes in
Polisher system DP reads 65 psid and stable
What is the corrective action or this alarm?
throttle condensate demin bypass valve to reduce to less than 60 psid
“A” and “B” main condensate pumps are running.
COND PP AUTO TRIP/OVERCURRENT comes in
“A” pump tripped
How will the “C” condensate pump respond, and what actions are required?
“C” should have auto started. Operators required to check feed system and if necessary take manual control of the feed pump master speed controller
What is the expected discharge pressure of the condensate pump?
500 psig
