ML19262B995

LER 79-102/03L-0:on 791221,during Mode 1 Operation,Core C Protection Calculator Failed.Caused by Speed Input Failure. Since Failure Was in Conservative Direction,Unit Returned to Svc

ML19262B995
Person / Time
Site:	Arkansas Nuclear
Issue date:	01/18/1980
From:	Pendergraft R ARKANSAS POWER & LIGHT CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML19262B990	List: ML19262B989 ML19262B995 ML19262B997
References
LER-79-102-03L, LER-79-102-3L, NUDOCS 8001220392
Download: ML19262B995 (1)

Text

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NRC PORM 3E4 U. S. NUCLE AR REGUL ATORY COMMISSION (7 77)

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80 EVENT DESCRIPTION AND PROBABLE CONSEOUENCES h o a I During Mode 1 coeration. "C" Core Protection Calculator (CPC) failed. I gi All remaining CPC's were operable. The channel "C" DNBR and LPD trips iTI'TlI were hvnassed niacing the reactor trin logic in a 2 out of 3 secuence. I icisii This occurrence is similar to LER 50-368/79-082 . Reportable Per i rTrd1 T.S.6.9.1.9'.b. i o i l I i c ia l I .

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4J 43 as er CAUSE DESCR.PTION AND CORREC rtVE ACT6ONS h s o l Investigation revealed a failed speed input as the cause of the CPC i m I failure. 30 minutes after failure, speed indication returned to normal. i

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> 3 1 vative direction. the unit was returned to service. Within'three hours g i of initial failure, unit was operational per T.S. table 3.3- 1 Action 2a.,

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