ML20155G506

Proposed Tech Specs Re ECCS Actuation Instrumentation - LPCI A/B RHR Pump Start Time Delay Requirements & CS Sys A/B Pump Start Delay Requirements

ML20155G506
Person / Time
Site:	Vermont Yankee
Issue date:	11/02/1998
From:	VERMONT YANKEE NUCLEAR POWER CORP.
To:
Shared Package
ML20155G496	List: ML20155G492 ML20155G506
References
NUDOCS 9811090071
Download: ML20155G506 (7)

Text

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VYNPS TABLE 3.2.1 ,

EMERGENCY CORE COOLING SYSTEM AC1UATION INSTRUMCfTATION Core Spray - A & B (Note 1)

Minimum Number of Required Action When operable Instrument Minimum Conditions Channels per Trip for operation System Trio Function Trio Level Settina are Not satisfied 2 High Drywell Pressure 1 2 5 psig Note 2 2 ,

Low-Low Reactor vessel Water __82.5*

> above top of Note 2 Level enriched fuel 1 Low Reactor Pressure 300 1 P 5 350 psig Note 2 l (PT-2-3-56C/D(H))

2 Low Reactor Pressure 300 1 P 5 350 psig Note 2 l

(PT-2-3-56A/B(H) & 52C/D(H))

1 (14A-K16A & B) onds he.pij Note 2 2 - Fu=y (E-so-1A/B) Discharge >100 psig Note 5 Pressure Auxiliary Power Monitor -- Note $ t 1

Note 5 I 1 Pump Bus Power Monitor --

Trip System Logic -- Note 5 1

I 9911090071 981102~

PDR ADOCK 05000271 P PDR t ja Anendment No. 44, 68, 449, 441,144,M2

VYNPS TABLE 3.2.1 ~

(Cont'd)

D4EROENCY CORE COOLitK2 SYSTEM ACWATION INSTRUMENTATIotl Low Pressure Coolant Injection System A & B (Note ~1)

Required Action When Hinimum Number of Minimum conditions Operable Instrument. for Operation Channele per Trip are Not Satisfied System Trio Function Trio Level Settina 300 g p g 350 peig Note 2 1- Low Reactor Pressure l

. (PT-2-3-56C/D(H))

$ 2.5 peig Note 2 2 High Drywell Pressure (PT-10-101A-D(H)) .

182.5" above top of Note 2 2 Low-Low Reactor vessel Water enriched fuel Level M Delay (10A-K51A & J 0 seconds [ [ Note 5 Note 5 1 Reactor Vessel Shroud Level 12/3 core height Note 5 1 Time Delhy (10A-K72A,p B) 560 seconds 3 $ (, f f Note 5 1 '! == h (10A-K50A & B) haeconde " Note"2-n==u Pressure 100 g p 5 150 psig 1

(PS-2-128A & B) Note 5 RHR Pump A & C Discharge A100 peig 2 per pump Pressuro ' Note 2 High Drywell Pressure $ 2.5 psig

• 2 (PT-10-101A-D(S1))

r Amendment flo. H , 44. 68, He,

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VYNPS l

Egg, 3 . 5. (Cont'd) n e Degraded Grid Protective System has been installed be to assure thatsubjected to sustaine safety-related electrical equipment will notThis systemthe incorporates voltage relays on 41 degraded voltage. minimum voltage Dnergency Buses 3 and 4 which damage areety-related of saf set to actuate at equipment. l required to prevent for 10 seconds, eitherBased relayupon willan If Degraded Grid conditions exist l actuate an alarm to alert operators of this condition.of these conditions the ope disconnect the off-site power. In addition, if an ESP signal is for assessment initiated in conjunction with low voltage below the relay seepoint 10 seconds, the off-site power will be automatically disconnected.

The Reactor Core Isolation Cooling (RCIC) System provides makeup water to or replace the reactor vessel during shutdown and isolation to supplementthe use of the Emergency C of a the normal makeup sources withoutThe RCIC Reactor System is initiated vessel highautomatically water upon rece Systems.

reactor vessel low-low water level signal. However, the system level signal results in shutdown of the RCIC System. reactor vessel low-low water level signal.

on a subsequent will restart suction from the condensate We RCIC System is normally lined up to takeSuetion will automatically switch over from t tank storage storage tank. tank to the suppression pool on low condensate storage level.

Upon receipt of a LOCA initiation signal, if normal AC power is available, all RHR pumps both Core Spray pumps start simultaneously with no intentional time delay. If normal AC power is not available, RHR pumps A and D start immediately on restoration of power, RHR pumps B and C start within 3 to 5 seconds of restoration of power and both Core Spray pumps start within 8 to 10 seconds of restoration of power. The purpose of these time delays is to stagger the star the RHR and Core Spray pumps on the associated Division I and Division 2 Buses, thus limiting i

the starting transients on the 4.16 kV emergency buses. De time delay functions are only necessary when power is being supplied from the standby power sources (EDGs). The time delays remain in the pump start logic at all times as the time delay relay contact is in pa the Auxiliary Power Monitor relay contact. Either contact closure will initiate pump start. Thus, the time delays do not affect low pressure ECCS pump operation with normal AC power j available. With normal AC power not available, the pump start relays which would have started the B and C RHR pumps and both Core Spray pumps are blocked by the Auxiliary Power Monitor contacts and the pump start time delay relays become the controlling devices.

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79 Amendment No. 94, 111 1 f

VERMONT YANKEE NUCLEAR POWER CORPORATION Docket No.50-27i BV'Y 98 18 .

, Page 1 of 1 '

ATTACHMENT 4 Revised New Technical Specification Paaae 1

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g p3 TABLE 3.2.1 .

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EMERGENCY CORE COOLING SYSTEM ACTUATION INSTRUMENTAT*ON- ,

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.i Core Spray - A & B (Note 1) [

Minimum Number of Required Action When }

Operable Instrument Minimum Conditions  ;

Channels per Trip . for Operation .!

System Trip Function Trip Level Setting are Not Satisfied  !

2 High Drywell Pressure $2.5 psig- Note 2 [

2 Low-Low Reactor Vessel Water >82.5" above top of Note 2 .

Level enriched fuel j 1 Low Reactor Pressure 300 $ P $ 350 psig. . Note 2 I (PT-2-3-56C/D(M)) f 2 Low Reactor Pressure 300 $ P $ 350 psig Note 2 (PT-2-3-56A/B(M) & 52C/D(M))

l 1 Pump Start Time Delay 8 $ t $ 10 seconds Note 2 (14A-K16A & B) 2 . Pump (P-46-1A/B) Discharge >100 psig- Note 5 I Pressure i L

1 . Auxiliary Power Monitor --

Note 5 {,

1 Pump Bus Power Monitor --

Note 5 [

2 Trip System Logic --

Note 5  :

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i Amendment No. 44, 68, . 4-14, 4M, 444, -142- 38 [

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VYNPS TABLE a.2.1 (Cont'd) ,

EMERGENCY CORE COOLING SYSTE.M ACTUATION INSTRUMENTATION Low Pressure Coolant Injection System A & B (Note'1)-

Minimum Number of Required Action When -[

Operable Instrument Minimum conditions .

. Channels per Trip for Operation System Trip Function Trip Level Setting are Not Satisfied  !

1 Low Reactor Pressure 300 $ p $ 350 psig Note 2.

(PT-2-3-56C/D(Mi) 1 2 High Drywell Pressure $2.5 psig Note 2 (PT-10-101A-D(M))

2 Low-Low Reactor Vessel Water 282.5" above top of Note 2 Level enriched fuel 1 Reactor Vessel Shroud Level 22/3 core height Note 5 1 Time Delay (10A-K72A & B) <60 secands Note 5 1 Pump-Start Time Delay 3 $ t 3 5 seconds Note 5

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l (10A-K50A & B) 1 Low Reactor Pressure 100 $ p 5 150 psig Note 2 (PS-2-128A & B) 2 per pump RHR Pump A & C Discharge 2100 psig Note 5 Pressure 2 High Drywell Pressure $2.5 psig Note 2 (PT-10-101A-D(S1))

Amendment No. 44, 44, 68, 444, 44e 39 i

VYNPS BASES: ' 3.2~ (Cont'd)

The Degraded Grid Protective System has been installed to assure that safety-related electrical equipment will not be subjected to sustained degraded voltage. This system incorporates voltage relays on 4160 Volt Emergency Buses 3 and 4 which are set to actuate at the minimum voltage required to prevent damage of safety-related equipment.

If Degraded Grid conditions exist for 10 seconds, either relay will actuate an alarm to alert operators of this condition. Based upon an assessment of these conditions the operator may choose to manually disconnect the off-site power.

In addition, if an ESF signal is initiated in conjunction with low voltage below the relay setpoint for 10 seconds, the off-site power will be automatically disconnected.

The Reactor Core Isolation Cooling (RCIC) System provides makeup water to the ]

reactor vessel during shutdown and isolation to supplement or replace the normal '

makeup sources without the use of the Emergency Core Cooling Systems. The RCIC j System is initiated automatically upon receipt of a reactor vessel low-low we.cer l level signal. Reactor vessel high water level signal results in shutdown of the l RCIC System. However, the system will restart on a subsequent reactor vessel low-low water level signal. The RCIC System is normally lined up to take

' suction from the condensate storage tank. Suction will automatically switch over from the condensate storage tank to the suppression pool on low condensate storage tank level.

Upon receipt of a LOCA initiation signal, if normal AC power is available, all )

RHR pumps and both Core Spray pumps start simultaneously with no intentional  !

time delay. If normal AC power is not available, RHR pumps A and D start l immediately on restoration of power, RHR pumps B and C start within 3 to 5 seconds of restoration of power and boch Core Spray pumps statt within 8 to 10 seconds of restoration of power. The purpose of these time delays is to stagger  ;

the start of the RHR and Core Spray pumps on the associated Division 1 and 1 Division 2 Buses, thus limiting the starting transients on the 4.16 kV emergency buses. The time delay functions are only necessary when power is being supplied from the standby power sources (EDGs). The time delays remain in the pump start logic at all times as the time delay relay contact is in parallel with the I Auxiliary Power Monitor relay contact. Either contact closure will initiate pump start. Thus, the time delays do not affect low pressure ECCS pump operation with normal AC power available. With normal AC power not available, the pump start relays which would have started the B and C RHR pumps and both Core Spray pumps are blocked by the Auxiliary Power Monitor contacts and the pump start time delay relays become the controlling devices.

l Amendment No. M, 4M 79