ECCS

Question 1

RHR P and T requirements

Answer 1

P < 360

T < 350

Question 2

Where can RHR take suction?

What cools the RHR for each source?

Answer 2

HLs 1 and 4 - CCW
RWST - nothing
Sump - CCW

Question 3

Where can RHR discharge?

Answer 3

All cold legs
Loops 2 and 3 HLs
CVCS
RWST
SIP & CCP suction

Question 4

Normal flow path for RHR

Answer 4

Loops 1 and 4 HLs
Pump
HX
Cold legs and CVCS

Question 5

RHR flow path for flooding the cavity

Answer 5

RWST
Pump
HX
Cold legs

Question 6

RHR flow path for draining the cavity

Answer 6

Loops 1 and 4 HLs
Pump
HX
RWST

Question 7

RHR flow path for cold leg recirc

Answer 7

Sump
Pump
HX
Cold legs, SIP, CCP

Question 8

What legs does RHR connect to the RCS (injection and suction)?

Answer 8

Inject
All cold legs
HLs 2 and 3

Suction
HLs 1 and 4

Question 9

What legs does SIP connect to (injection and suction)?

Answer 9

Injects to all cold legs

Injects to HL 1 and 4

Question 10

What legs does CCP connect to (injection and suction)?

Answer 10

Injects to all cold legs

Question 11

Where do SIP and CCP take suction from in injection vs recirc?

Answer 11

RWST

RHR discharge

Question 12

Injection pressure in the accumulators

Answer 12

650

Question 13

What is PZR level controlled to during ECCS actuation?

Answer 13

None. All pumps are at 100% and controlled by RCS backpressure.

Question 14

When can you terminate SI?

Answer 14

PZR > 4%
PZR P stable or increasing
Sub cooling > 30 F
Total AFW flow > 260k

Question 15

Why about the ECCS requires rods to insert after a trip?

Answer 15

It was sized only for decay heat removal.

Question 16

Fist 4 steps of E0

Answer 16

Verify reactor trip (DRPI, breakers, IR flux)
Verify turbine trip (stop valves)
Power to vital AC (diesels)
Check if SI actuated (annunciators)

Question 17

What happens after a SIS?

not all inclusive list

Answer 17

Reactor trip -> turbine trip
FWIS & AFW starts
All ECCS pumps start
CCP signs to RWST
ESW pumps start

Question 18

3 modes of ECCS and where pumps align / discharge

Answer 18

Injection:
- All align to RWST
- All inject to CLs
Cold recirc:
- RHR aligns to sump, SIPs and CCPs align to RHR
- All inject to CLs
Hot recirc:
- Same alignment as Cold recirc
- RHR and SIP inject to HLs, CCP to CLs