CCW Flashcards
LCO 3.7.7 “CCW System” requirements
2 CCW trains shall be operable
CCW safety related loads
SDC HX
ESS seal cooling
CCW non-safety related loads
PCP leak off and oil coolers Letdown HX SFP HX Evaps Waste gas compressors CRDM seals Charging pump oil coolers P-55A fluid drive Vac degas pumps seal cooling Shield cooling HX PCS sample coolers
General CCW temp/press ratings
65-140 F
150 psi
CCW flow requirements
Normal - 4367 gpm
SDC - 7179 gpm
SIS - 1697 gpm
CHP/RAS - 4573 gpm
Normal CCW operation
1 pump running, 2 in standby
2 HX’s in service
Normal TCV’s throttle service water flow to control CCW temp 72-88 F
SDC CCW operation
2 pumps running, 1 in standby
2 HX’s in service
Placed in service when PCS <265 psi and 300 F
CCW pump power supplies
P-52A/C - C bus
P-52B - D bus
CCW pump flow capacity
6000 gpm
CCW pump auto starts
Low header pressure - 80 psi with pump in standby
SIS
NSD sequencer
DBA sequencer
CCW pump auto stops
Load shed
Overcurrent
CCW pump CR controls
Close - starts pump, takes it out of standby
Trip - stops pump, takes it out of standby
CCW pump standby feature
Push button
Allows auto start at 80 psi header pressure
How can CCW pump standby be disabled
Take pump hand switch to trip
Pump start
Undervoltage on pump’s respective bus
CCW HX max flow
4700 gpm corresponds to DP of:
E-54A - 24.1 psid
E-54B - 22.0 psid
CCW HX preferred DP
1 pump - 6-8 psid
2 pumps - 12-16 psid
RIA-0915 CCW rad monitor function
Monitors CCW pump discharge
Swaps CCW surge tank vent from atmosphere to VGCH when high rad is detected
Where can CCW HX inlet CV-0945/0946 be operated from and how do they fail
Fail open
Operated from CR or C-33
CCW HX TCV CV-0821/0822 function
Control SW flow through CCW HX to control CCW temp
Fail closed
CCW HX temp alarm set points
71-89 F
Where can SDC HX inlet CV-0937/0938 be operated from and how do they fail
Fail open
Operated from CR or C-33
Open on SIS, and can’t be closed until SIS is reset
How does CCW to SFP and Evaps CV-0944A fail and how does it respond on SIS
Fails closed
Closes on SIS
Stays closed until SIS is reset, or handswitch is taken to bypass to allow cooling of SFP
CV-0944A control switch positions
Open - opens valve unless SIS is present
Close - closes valve
Bypass - Opens valve if SIS is present, closes valve if SIS isn’t present
CCW to Rad Waste Evaporators CV-0944/CV-0977B function
Fails closed
No indication of valve position in CR, only indication is on C-105
Closes on SIS to isolate CCW flow to non-essential loads
ESS Pumps CCW Supply/Return CV-0913/CV-0950 function
Fails open
Operated from CR or C-33
Normally open, causing locked in alarm in the CR
ESS Pumps CCW Supply CV-0949/CV-0948/CV-0947 function
Fails open
Operated from CR or C-33
Normally electrically locked open
ESS pumps CCW low flow alarm setpoints
WESG - 9-11 gpm
EESG - 4-6 gpm
Indicates loss of cooling water flow from either CCW or SW depending on which one is aligned.
WESG is higher than EESG because there are more pumps in WESG
CCW to and from Containment CV-0910/CV-0911/CV-0940 function
Fails open to ensure loss of air/power won't isolate CCW to CTMT Closes on CHP Right channel - 0940 Left channel - 0911 Either channel - 0910
Differences between CV-0910 CCW to CTMT and CV-0911/0940 CCW from CTMT
CCW to CTMT has a check valve, so no accumulator
CCW from CTMT valves have accumulators good to hold valve closed for 4 hours with a loss of air
CCW to/from CTMT control switches
Close - Valve closes as long as no loss of air/power
Open - Valve opens regardless of CHP signal
Auto - Valve is open until CHP signal present, then valve will close until CHP signal is clear
T-3, CCW Surge Tank, normal operating range
47-74%
Tank is big enough so a CCW temp increase from 60 F to 140 F won’t cause a high level alarm
T-3, CCW Surge Tank, alarm setpoints
35-93%
T-3, CCW Surge Tank, sources of inleakage
SDC HX SFP HX Letdown HX PCP seals CRD seals
T-3, CCW Surge Tank, sources of out leakage
Evaps Charging pumps lube oil coolers P-55A fluid drive Vac Degas Pumps Shield cooling HX PCP lube oil coolers Waste gas compressors PCS sample cooler ESS pump seals
CCW surge tank fill CV-0918 function
No Handswitch, only indication
Opens at 47% to fill tank from T-81
Closes at 74%
Fails closed
CCW surge tank vent CV-0915 function
No Handswitch, only indication
Fails to VGCH
Normally aligned to atmosphere, re-aligns to VGCH on high rad signal
CCW response to SIS with offsite power
All 3 pumps start
OPEN:
• CV-0937/CV-0938, SDC HX Cooling Inlets
• CV-0913, ESS Pumps CCW Supply (normally open)
• CV-0950, ESS Pumps CCW Return (normally open)
Close:
• CV-0944A, CCW to SFP & RW Evaporators
• CV-0944, CCW to Rad Waste Evaporators
• CV-0977B, CCW Return From Rad Waste Evaporators
CCW response to SIS with loss of offsite power
P-52A & B start after 23 seconds
P-52C starts after 40 seconds if low pressure condition
OPEN:
• CV-0937/CV-0938, SDC HX Cooling Inlets
• CV-0913, ESS Pumps CCW Supply (normally open)
• CV-0950, ESS Pumps CCW Return (normally open)
Close:
• CV-0944A, CCW to SFP & RW Evaporators
• CV-0944, CCW to Rad Waste Evaporators
• CV-0977B, CCW Return From Rad Waste Evaporators
CCW response to a loss of offsite power
P-52A & B start after 23 seconds
P-52C starts after 40 seconds if low pressure condition
CCW response to CHP
All 3 pumps start
OPEN:
• CV-0937/CV-0938, SDC HX Cooling Inlets
• CV-0913, ESS Pumps CCW Supply (normally open)
• CV-0950, ESS Pumps CCW Return (normally open)
Close:
• CV-0944A, CCW to SFP & RW Evaporators
• CV-0944, CCW to Rad Waste Evaporators
• CV-0977B, CCW Return From Rad Waste Evaporators
• CV-0910, CCW to CTMT
• CV-0911, CCW from CTMT
• CV-0940, CCW from CTMT
LCO 3.7.7 “CCW System” applicability
Modes 1-4
LCO 3.7.7 “CCW System” required actions if less than 100% of the required post accident CCW cooling capability available
Enter LCO 3.0.3 IMMEDIATELY
What are the requirements for 100% required CCW post accident cooling with only 1 CCW pump?
1 CCW containment header valve, CV-0910, CV-0911, or CV-0940, operable
AND
2 CCW isolation valves for non-safety related loads outside containment, CV-0944A and CV-0944 or (CV-0977B)
What are the requirements for 100% required CCW post accident cooling with only 2 CCW pumps?
1 CCW containment header valve, CV-0910, CV-0911, or CV-0940, operable
OR
2 CCW isolation valves for non-safety related loads outside containment, CV-0944A and CV-0944 or (CV-0977B)
What are the consequences of having CCW to/from containment isolation valves (CV-0910, CV-0911, and CV-0940) in open position instead of auto?
Valves will not close on CHP
What are the consequences of not having 2 CCW pumps in service when stroking open SDC heat exchanger inlet valves?
Standby CCW pump could start
What are the consequences if CCW heat exchanger outlet temperatures get too high?
PCP seal temperatures will elevate
