05000368/LER-1980-060, Updated LER 80-060/03X-2:800730 & 1202,D Core Protection Calculator Failed.C Core Protection Calculator Failed on 801120.Watchdog Timer Timed Out Preventing Console Communications.Core Protection Calculator Sys Reinitialized

Updated LER 80-060/03X-2:800730 & 1202,D Core Protection Calculator Failed.C Core Protection Calculator Failed on 801120.Watchdog Timer Timed Out Preventing Console Communications.Core Protection Calculator Sys Reinitialized

ML19351F394
Person / Time
Site:	Arkansas Nuclear
Issue date:	01/07/1981
From:	Bramlett L ARKANSAS POWER & LIGHT CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML19351F380	List: 05000368/LER-1980-060, Updated LER 80-060/03X-2:800730 & 1202,D Core Protection Calculator Failed.C Core Protection Calculator Failed on 801120.Watchdog Timer Timed Out Preventing Console Communications.Core Protection Calculator Sys Reinitialized
References
LER-80-060-03X, LER-80-60-3X, NUDOCS 8101120389
Download: ML19351F394 (1)

LER-1980-060, Updated LER 80-060/03X-2:800730 & 1202,D Core Protection Calculator Failed.C Core Protection Calculator Failed on 801120.Watchdog Timer Timed Out Preventing Console Communications.Core Protection Calculator Sys Reinitialized

Event date:
Report date:
3681980060R00 - NRC Website

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1. 4 R(,QH T 0 4 T E 80 EVENT DESCRirTION AND PRC8 ASLE CONSEQUENCES h (HD IDuring Mode 1 coeration. the "D" Core Protection Calculator (CPC) failed 1 EIT) lon 7/30/80 and 12/2/80.

The "C" CPC failed on 11/20/80.

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ITrips were bypassed on the affected CPC channel, placing the Reactor i

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Similar LER's for CPC "C" are 50-368/80-002,79-098, i 179-096: For the "D" CPC is 50-368/80-008: for "A" CPC are 50-368/80-51, I

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