CVCS Charging

Question 1

What is the power supply for CHN-501

Answer 1

PHA-M35 via passthrough in NHN-M72

Question 2

What automatic functions are there for CHN-501

Answer 2

-Will auto close on Lo-Lo VCT level 5%
-Will auto open when VCT Lo-Lo resets AND CHN-536
is closed

Question 3

What does the CH provide to CVCS

Answer 3

• RCS makeup
• RCP Seal Inj.
• PZR aux spray

Question 4

Where can the CH pumps take suction from?

Answer 4

• VCT via CHN-501
• Blended Makeup via CHN-527
• Directly from BAMP via CHN-514
• RWT Gravity Feed from CHN-536
• Alternate Suct. from RWT via CHB-327

Question 5

Where can the CH pumps discharge to?

Answer 5

-Charging header
-HPSI A cold leg
-HPSI B hot leg
(a cold, be hot)

Question 6

How are the Charging pumps protected from cavitation damage

Answer 6

Low Suction press trip at 13 psia (CH pump will be anti-pumped after trip)

Question 7

What are the modes of operation for the CH pumps

Answer 7

-Auto-After-START
     Does not respond to PLCS
-Auto-After-Stop
     Operated by the PLCS
-Stop
     Opens the pump breaker
-Pull To Lock
     Prevents the pump from running under any cond.

Question 8

How do you clear a CH pump anti-pump condition

Answer 8

Take the Hand switch to STOP

Question 9

What HU trap is associated with CH pump running lights

Answer 9

The lights are breaker position and does NOT mean the pump is running

Question 10

What is the power supply for CH indicating lights

Answer 10

PK

Question 11

Following a LOP what is the status of the CH pumps
Always Running-
Normal Running-
STBY-

Answer 11

• Anti-Pump
• Anti-Pump
• No effect

Question 12

Following a LOOP what is the status of the CH pumps
Always Running-
Normal Running-
STBY-

Answer 12

• Anti-Pump
• Restarted by PLCS
• no effect

Question 13

Following a SIAS what is the status of the CH pumps
Always Running-
Normal Running-
STBY-

Answer 13

• No Effect
• No Effect
• No Effect

Question 14

Following a LOP W/ SIAS what is the status of the CH pumps
Always Running-
Normal Running-
STBY-

Answer 14

• Load Shed Will restart after 40 sec. b/c SIAS
• Load Shed Will restart after 40 sec. b/c SIAS
• Controlled by PLCS

Question 15

Following a LOOP W/ SIAS what is the status of the CH pumps
Always Running-
Normal Running-
STBY-

Answer 15

• Load Shed Will restart after 40 sec. b/c SIAS
• Load Shed Will restart after 40 sec. b/c SIAS
• Controlled by PLCS

Question 16

How long can CH pumps run without seal water

Answer 16

Up to 50 hours

Question 17

What are indications of gas binding of a CH pump

Answer 17

• Loss of pump suction
• Flow/press fluctuations
• Isolation of letdown due to Regen HX temp.

Question 18

What is CHN-524, what is its normal position and why

Answer 18

• Charging to CNTMT isolation valve
• Normally OPEN with power removed
• commitment to NRC to prevent isolating Aux Spray

Question 19

What is the purpose of CHN-239

Answer 19

prevents the loss of Aux Spray if CHN-240 fails open

Question 20

What is the purpose of CHN-240

Answer 20

maintains CH header backpressure for Aux Spray approx. 105 psid

Question 21

What is the purpose of CHA-205 & CHB-203

Answer 21

Aux Spray valves provide PZR press. control when normal control is not available

Question 22

What is the power supply for Aux Spray valves

Answer 22

PK

Question 23

What auto action is associated with Seal Inj. Iso. valve CHN-231

Answer 23

Closes on Temp Hi/Lo 150 or 70*F

Question 24

What is the Fail position for CHN-241, 242, 243, 244 Seal inj. flow control valves?

Answer 24

Fail OPEN on loss of:

• Air
• Power to solenoids (NKN-D42)
• Power to flow controller (NNN-D11/12)

Question 25

What HU trap is associated with Seal Inj. flow controllers

Answer 25

They are reverse acting, | 100% output closes the valve

Question 26

What will cause CHA/B-505/506 Seal Bleed off CNTMT iso valves to close

Answer 26

- Loss of Air - Loss of power (PK) - CSAS (can be overridden)

Question 27

At what temperatures does the Regen HX alarm, & Isolate

Answer 27

- Alarms at 395*F | - Isolates at 413*F

Question 28

Describe the relation b/w CH flow, LD flow, and Bleedoff flow

Answer 28

``` CH = LD + Bleedoff 88 = 76-ish + 12-ish ```

Question 29

What SESS alarms are associated with CH

Answer 29

CHA/B-505/506 will cause a Blue SEAS light if not FULLY closed with actuation signal present

Question 30

What is required to make CH pumps "Functional" online

Answer 30

At least 2 charging pumps shall be functional | -Enter TLCO - Immediately

Question 31

What is required to make CH/ boration "Functional" shutdown

Answer 31

At least 1 CH pump OR 1 HPSI OR 1 LPSI shall be functional -Suspend Core Alts - Immediately -Suspend (+) reactivity ops - Immediately

Question 32

What is required for Aux Spray to be "Functional"

Answer 32

Both Aux Spray Valves shall be Functional | -Enter TLCO - Immediately