ML20071N657

Proposed TS Page 15.3.7-7,providing Clarification of Standby Emergency Power LCO

ML20071N657
Person / Time
Site:	Point Beach
Issue date:	08/01/1994
From:	WISCONSIN ELECTRIC POWER CO.
To:
Shared Package
ML20071N656	List: ML20071N652 ML20071N657
References
NUDOCS 9408080115
Download: ML20071N657 (1)

Text

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The. bus 4ie-breaker' specifications.h' ave provisions th tithe'requiridfredundant' decay heat.retcoval for the' shutdown: unit and the~ required redundantishared engineered safety features forlthe other unit arel operable. The specification that' applies onlyl to the'. defueled condition does not have the. provisionf for.the required redundant decay heatLremoval. for. the shutdown unit. lItL has1 provision L foe verifying,the adequacy of La' single; trainf ofL spent fuel'poolt coolincyinLlieu .oftthe consideration.lof: decay; heat. removal for. a reactor Lin cold ! shutdown; The Point Beach DC electrical system has been modified so that each of the four main DC distribution buses, which are shared between the two units, has its own power supplies consisting of a safety-related station battery (DOS, D06, D105, 0106) and a battery charger. In addition to these bus-specific power supplies, a swing safety-related battery (D305) is installed which is capable of being connected to any one of the four main DC distribution buses. Swing battery chargers are also provided. Under normal circumstances, one battery and one battery charger are connected in each main DC distribution bus. The battery charger normally shall be in service on each battery so that the batteries will always be at full charge in anticipation of a loss-of-AC power incident. Under unusual circumstances, two of the five safety-related batteries may be out of service for a limited period of time provided one of the two out-of-service batteries is returned to service within the time periods specified in Specif' ;ation 15.3.7.B. I .hi . These limiting conditions for operation ensure that adequate DC power will always be available for starting the emergency generators and other emergency uses.

The emerge'ncy ' die'selige'nefatorsiafeith'efsoutbeslof; standby emerg'erickjower? The support systems necessary to be operable to ensure the operability of the emergency diesel generators (EDGs) are the EDG starting air system, E.DG fuel oil system, EDG ventilation system, and EDG DC control power. The standby" emergency power supply for a.4160? Volt and assobiated 480 Volt safeguards busLconsistslof an operable EDG, including. all' required support. systems,7and anioperable: output.

br.eaker to that 4160 Vol.t safeguards;. bus. '

The LCOsifor the!standbi emergency l power supplies require 1the redudda'ntistsridbi emergency power supplies to' be started within'24. h.ours of;entrylinto'thsse LCOs.

If: the standby emergency pwer supplyLLCO is exited l wit'iin 24? hours,jthen startiny t

of the redundant. standby ecrgency power supplies is._not required. :.If;the.tC0 was entered due to"a standby emergency power supply failure;and the LC0 wasr exited within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, then an evaluation must be: completed aslsoon;as..Lpossible'.' w ithin 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of entry into the LCO-to show that the redundant standby ~ power supplies are not susceptible to thatifailure by common cause'or the redundant standby emergency' power supplles must be started to' prove that: failure by common.cau'sb does not exist within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of entry into the LCO.

The EDG starting air system is considered operable when 1) all three starting air bottles in each bank are operable, 2) the starting air banks can be maintained at a minimum pressure of 165 psig, 3) the air bank crossconnect valve is shut unless 9400080115 940003 PDR P ADOCK 05000266 PDR Unit 1 - Amendment No. 15.3.7-7 Unit 2 - Amendment No.