05000368/LER-1979-102-03, /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

/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: 05000368/LER-1979-102, Forwards LER 79-102/03L-0 & Updated LER 79-008/03X-1 05000368/LER-1979-102-03, /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
References
LER-79-102-03L, LER-79-102-3L, NUDOCS 8001220392
Download: ML19262B995 (1)

LER-1979-102, /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

Event date:
Report date:
3681979102R03 - NRC Website

text

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"C" Core Protection Calculator (CPC) failed.

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a 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

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30 minutes after failure, speed indication returned to normal. i No cause of failure could be determined.

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