ML17266A091

LER 79-025/03L-0 on 790720:variable High Power Trip Setpoint in Core Protection Calculator Failed to Track Reactor Power. Caused by Power Supply in Core Protection Calculator Failing Due to Filter Capacitor Failure

ML17266A091
Person / Time
Site:	Saint Lucie
Issue date:	08/17/1979
From:	Schoppman M FLORIDA POWER & LIGHT CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML17207A322	List: ML17207A321 ML17266A091
References
LER-79-025-03L, LER-79-25-3L, NUDOCS 7908300711
Download: ML17266A091 (1)

Text

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8VSNT OSSCRIPTION ANO RO8ASI.8 CONSSOUS5VCSS ~10 Ouring power reduction, the variable high power trip setpoint on channel "C" in the core protection calculator failed to track reactor power.

~03 Action in accordance with Technical Specification 3.3.1.1 was initiated.

A;0 5 volt power supply was repaired and the channel restored to operable condition within the time 'limit s ecified. There was no adverse affect plant. Three channels remained operable and no additional action 'n'he This was the first occurrence of this type.

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The tion due to a failed power supply in the core protection calculator. The ower suo 1 failed because of a failed filter capacitor. The cause of. the capacitor failure is not known. The most probable cause is normal end of life of an electronic component.

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'.0'A7318 OP PRSPAR cR M. A. Schoppman (305) 552-3802