05000298/LER-1981-008-03, /03L-0:on 810426,reactor Vessel Level Switch LIS-72C,Switch-4,caused Continuous Annunciator 9-3-1/8-2 Alarm.Caused by Failure of Yarway Model 4418C Level Indicating Switch,Due to Film Buildup Between Contacts

/03L-0:on 810426,reactor Vessel Level Switch LIS-72C,Switch-4,caused Continuous Annunciator 9-3-1/8-2 Alarm.Caused by Failure of Yarway Model 4418C Level Indicating Switch,Due to Film Buildup Between Contacts

ML20004D686
Person / Time
Site:	Cooper
Issue date:	05/26/1981
From:	Marker D NEBRASKA PUBLIC POWER DISTRICT
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20004D674	List: 05000298/LER-1981-008, Forwards LER 81-008/03L-0.Detailed Event Analysis Encl 05000298/LER-1981-008-03, /03L-0:on 810426,reactor Vessel Level Switch LIS-72C,Switch-4,caused Continuous Annunciator 9-3-1/8-2 Alarm.Caused by Failure of Yarway Model 4418C Level Indicating Switch,Due to Film Buildup Between Contacts
References
LER-81-008-03L, LER-81-8-3L, NUDOCS 8106090647
Download: ML20004D686 (1)

LER-1981-008, /03L-0:on 810426,reactor Vessel Level Switch LIS-72C,Switch-4,caused Continuous Annunciator 9-3-1/8-2 Alarm.Caused by Failure of Yarway Model 4418C Level Indicating Switch,Due to Film Buildup Between Contacts

Event date:
Report date:
2981981008R03 - NRC Website

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8 60 61 OOCKET NUM8ER 68 69 EVENT DATE 14 75 REPOR T DATE 80 EVENT DESCRIPTION AND PROBABLE CONSEQUENCES O'o Iol2l l During a routine reactor cold shutdown for refueling, reactor vessel level switch l g o i3i l LIS-72C, switch #4, was causing annunciator 9-3-1/8-2 to alarm with reactor vessel l lolAl l level at approximately 140"-150", (alarm point -37"). The redundant level switches l l o I s l I were operable. There were no adverse affects to public health and safety.

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