ML20153F420

Corrected Proposed Tech Specs Bases Page B 3.8-94 Re SVC Protection Sys

ML20153F420
Person / Time
Site:	Clinton
Issue date:	09/23/1998
From:	ILLINOIS POWER CO.
To:
Shared Package
ML20153F414	List: ML20153F420
References
NUDOCS 9809290122
Download: ML20153F420 (1)

Text

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4 , . Attachment 2 to U-603084

,. Page 4 of 4 SVC Protection Systems B 3.8.11

[ BASE 3 APPLICABLE sources, are designed to provide sufficient capacity, SAFETY ANALYSES capability, redundancy and reliability to ensure the ,

(continued) availab'ility of necessary power to ESF systems so that the I fuel, reactor coolant system, and containment design limits are not exceeded. The RAT and ERAT SVCs provide voltage support, when required, from the associated offsite source .

circuits to the ESF busses and equipment supplied by those l circuits. At the same time, failure and risk analyses performed for the SVCs demonstrate that a protection system for each SVC is necessary to protect ESF equipment from l potential SVC failure modes that could damage or degrade the i Class 1E equipment. OPERABILITY of the SVC Protection l Systems is thus consistent with minimizing the potential for 1 SVC failures to damage or degrade required ESF equipment.

Probabilistic risk assessment has shown the SVC Protection i Systems to be important for the protection of required ESF l systems and equipment. Therefore, the SVC Protection Systems satisfy Criterion 4 of the NRC Policy Statement.

LC0 Both redundant protection subsystems of a required SVC g

protection system are required to be OPERABLE to ensure no single failure will preclude protection on a valid signal.

Total SVC Protection System failure introduces the possibility of ESF equipment failure or degradation of ESF equipment connected or capable of being automatically ,

connected to the busses supp,orted by the SVC(s). each oh

~

Ot is J An SVC rotectionSystemisconsideredOPERABLEwhen[both l SVC pr ection subsystem +# capable of automatically I opening M associated SVC main circuit breaker 1 n 1 response to postulated SVC failures that could potentia 17y degrade or damage ESF equipment. OPERABILITY of an SVC protection subsystem exists when it is energized and all essential components are OPERABLE, including the associated relays and ,

sensors (e.g., current transformers and potential transformers).

(continued) 9809290122 980923

( PDR ADOCK 05000461 P PDR CLINTON B 3.8-94 Revision No.

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