05000267/LER-1981-033-03, /03L-0:on 810427,helium Circulator 1C Speed/Wobble Modifier Malfunctioned Causing Loss of Plant Protective Sys Functions to High Speed Trip Circuits.Caused by Electronic Circuit Unbalance.Spare Speed Element Installed

/03L-0:on 810427,helium Circulator 1C Speed/Wobble Modifier Malfunctioned Causing Loss of Plant Protective Sys Functions to High Speed Trip Circuits.Caused by Electronic Circuit Unbalance.Spare Speed Element Installed

ML20004D666
Person / Time
Site:	Fort Saint Vrain
Issue date:	05/27/1981
From:	Gahm J PUBLIC SERVICE CO. OF COLORADO
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20004D656	List: 05000267/LER-1981-033, Forwards LER 81-033/03L-0.Detailed Event Analysis Encl 05000267/LER-1981-033-03, /03L-0:on 810427,helium Circulator 1C Speed/Wobble Modifier Malfunctioned Causing Loss of Plant Protective Sys Functions to High Speed Trip Circuits.Caused by Electronic Circuit Unbalance.Spare Speed Element Installed
References
LER-81-033-03L, LER-81-33-3L, NUDOCS 8106090631
Download: ML20004D666 (1)

LER-1981-033, /03L-0:on 810427,helium Circulator 1C Speed/Wobble Modifier Malfunctioned Causing Loss of Plant Protective Sys Functions to High Speed Trip Circuits.Caused by Electronic Circuit Unbalance.Spare Speed Element Installed

Event date:
Report date:
2671981033R03 - NRC Website

text

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LICENSEE EVENT REPORT

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8 60 68 OoCKET NUMSER 68 69 EVENT OATE 74 75 AEPORT D ATE SQ tVENT DESCRIPTION AND PROSABLE CONSEQUENCES h l o 12 l l A malfunction of helium circulator 1C speed modifier caused loss of olant protective j

g o,3, l system function of high speed trips to one of three channels.

Reportable per Fort St.l f

to64l I Vrain Technical Specification AC 7.5.2(b)2 operation under a degraded mode of l

3 a,3 ; lLC0 4.4.1, Table 4.4-3.

No affect on plant operation.

Probable consequence was loss l I of high speed circulator trip function to one of three channels.

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1o is l i o 17 I I available and operable. No affect on public health or safety.

Similar reports l

RO 78-15, RO 79-41, and R0 80-71.

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