05000270/LER-1981-011-03, /03L-0:on 810806 & 07,RCS Subcooling Margin Monitor Was Inoperable & Backup Method Unavailable.Caused by out-of-svc Unit 2 Operator Aid Computer Due to Malfunction of AGRA2 Group Relay Board & Matrix Card

/03L-0:on 810806 & 07,RCS Subcooling Margin Monitor Was Inoperable & Backup Method Unavailable.Caused by out-of-svc Unit 2 Operator Aid Computer Due to Malfunction of AGRA2 Group Relay Board & Matrix Card

ML20010F828
Person / Time
Site:	Oconee
Issue date:	09/04/1981
From:	Kutzer J DUKE POWER CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20010F823	List: 05000270/LER-1981-011, Forwards LER 81-011/03L-0 05000270/LER-1981-011-03, /03L-0:on 810806 & 07,RCS Subcooling Margin Monitor Was Inoperable & Backup Method Unavailable.Caused by out-of-svc Unit 2 Operator Aid Computer Due to Malfunction of AGRA2 Group Relay Board & Matrix Card
References
LER-81-011-03L-01, LER-81-11-3L-1, NUDOCS 8109110384
Download: ML20010F828 (1)

LER-1981-011, /03L-0:on 810806 & 07,RCS Subcooling Margin Monitor Was Inoperable & Backup Method Unavailable.Caused by out-of-svc Unit 2 Operator Aid Computer Due to Malfunction of AGRA2 Group Relay Board & Matrix Card

Event date:
Report date:
2701981011R03 - NRC Website

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l f o 121 [On August 6 and 7,- 1981, the Unit 2 Opetator Aid Computer was out of service [

gresulting in inoperability of RCS Subcooling Margin Monitor and unavailability

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,,of a backup method to determine subcooling margin outside narrow range temper-l l

r ture indications (520 F - 620 F). This incident did not affect the operating, a

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6, 1981, which was corrected by replacing affected boards. August 7, 1981

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