E21 - LPCS

Question 1

What pressure does Inj valve open?

Answer 1

476 psig

Question 2

what will trip LPCS motor?

Answer 2

LSS

Motor Protection

Question 3

When does min flow valve open? close?

Answer 3

opens with pump running, and <1333 gpm

closes @ >1376 gpm

Question 4

How long is allowable to run LPCS on min flow?

Answer 4

30 minutes

Question 5

Does injection valve receive auto open signal on initiation?

Answer 5

yes, but does not open until <476 psig

Question 6

When will inj valve auto close?

Answer 6

NEVER

Question 7

When will the suction valve auto open?

Answer 7

NEVER. it will never auto close or open

Question 8

what flow should not be exceeded to prevent pump damage?

Answer 8

9100

Question 9

What is motor cold and how many start attempts?

Answer 9

80 minutes idle, 2 starts allowed

Question 10

what is motor hot? How many start attempts allowed?

Answer 10

Pump running for 30 minutes

1 restart allowed. additional allowed after 20 minutes idle

Question 11

What is the flow rate of LPCS?

Answer 11

7115 gpm @ 290 psid, 7450 gpm @ 125 psid

Question 12

What low pressure pumps start first and when? when do the other pumps start?

Answer 12

2. 5 seconds - LPCS/RHR C

7. 5 seconds - RHR A/B

Question 13

what does the min/flow line restrict flow to?

Answer 13

1250 gpm

Question 14

what flow will the jockey pump provide?

Answer 14

40 gpm @ 47 psig

Question 15

what’s the purpose of test return valve?

Answer 15

used for full flow testing returning to suppression pool

Question 16

when does LPCS initiate?

Answer 16

• 150.3” Rx level

1. 39 psig DW pressure

Question 17

what level is required in suppression pool for NPSH

Answer 17

> 14.5’ or

18’ 4 1/2” to be operable

Question 18

what cools LPCS pump room?

Answer 18

SSW A

Question 19

When can the inj valve F005 be manually opened after initiation?

Answer 19

<530 psig

Question 20

If pressure drops below 530 psig (manually open setpoint after initiation), how long after it goes back up can it still be manually opened?

Answer 20

15 minutes

Question 21

what pressure can LPCS inject at?

Answer 21

< 476 psig (pump starts… valve opens at 476)

Question 22

What is the suction source for LPCS?

Answer 22

Suppression pool

Question 23

What is the purpose of LPCS?

Answer 23

Automatically initiate to restore and maintain Rx water level to mitigate effects of a LOCA.
Sprays inside core shroud and directly onto fuel bundles.

Question 24

LPCS power supply?

Answer 24

15AA

Question 25

Purpose of the LPCS jockey pump?

Answer 25

keeps discharge line full to prevent water hammer and minimize injection time

Question 26

what is the additional purpose of the jockey pump?

Answer 26

provides fill water to div 1 suppression pool instrument reference leg

Question 27

what provides the manual over-ride of LPCS?

Answer 27

Loss of 15AA bus
Loss of logic power
Div 1 ECCS initiation signal is reset