ML20010F828

LER 81-011/03L-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

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: ML20010F822 ML20010F828
References
LER-81-011-03L-01, LER-81-11-3L-1, NUDOCS 8109110384
Download: ML20010F828 (1)

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

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,o,3, gresulting in inoperability of RCS Subcooling Margin Monitor and unavailability l ,, ,,of a backup method to determine subcooling margin outside narrow range temper-l g3,,, rature indications (520 F - 620 F). This incident did not affect the operating,

,,g,g status of Unit 2; thus, ti.e health and safety of the public were nct affected.

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l cAusE cEsemartics ANo c:anEc nvE ACTICNS Ii 4 a j [This incident was the result of a malfunction of AGRA2 group relay board and i

,,,,,imatrix card causing erratic readinm of points in the analog system on August ,

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

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