ML19316A442

LER 77-017/03L-01:on 771229,control Rod 4,group 6,dropped Into Core Causing Power Runback to 55%.Caused by Stator R70-046133 Short Due to Moisture Buildup & O-ring Seal Failure.Stator & O-ring Seals Were Replaced

ML19316A442
Person / Time
Site:	Oconee
Issue date:	02/28/1978
From:	Ken Wilson DUKE POWER CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19316A443	List: ML19316A442
References
LER-77-017-03L, LER-77-17-3L, NUDOCS 7912110706
Download: ML19316A442 (1)

Text

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o 2 I nivr!ne ormal oneration w'hile control rnd 4 2roon 6 was being withdrawn. I ib TTl I fr drneced into the core cauqine a nower ronback to 5 5 ?. . Attempts to raise i E I rod were unsuccessful. It was determined that a short in the stator caused g I"iTil I the rod to drop. The reactor was shutdown for replacement of the stator.  ;

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