ML19274E484

LER 79-005/03L-0 on 790218:malfunction in Computer Resulted in Control Element Assembly Pulse Counting Position Being Inoperable.Cause Traced to Circuit Card in Computer Memory; No Fault Discerned.Card Contacts Cleaned

ML19274E484
Person / Time
Site:	Millstone
Issue date:	03/16/1979
From:	NORTHEAST UTILITIES
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19274E483	List: ML19274E482 ML19274E484
References
LER-79-005-03L, LER-79-5-3L, NUDOCS 7903260246
Download: ML19274E484 (1)

Text

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[a 2 [ During steady state power operation, the plant computer experienced a nalfunction g This resulted in CEA pulse counting position being g

[TiITl [ and was taken out of service.

[~oE l inoperable. In accordance with Technical Specification action statcaent 3.1.3.d, l HJ Loperation continued and the conputer failure was corrected. The conputer and the g g,,) l CEA pulse counting indication system was restored to operable status within 5-1/2  ;

Sinilar events LER's 77-41/3L, 9/26/77; 78-12/3L, 6/27/78; 78-21/3L, _ g o 7

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[Il0[ll Q 4t 47 JJ 3's CAUSE DESCmPTION AND CORHECTIVE AC NONS h Ilowever, no fiiT_) [_Tip failure was traced to a circuit card in the conputer nenary. [

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~ W I fault could be found in the circuit card. The card contacts were cleaned and the g,,,; l card was reinstalled. The conputer was restarted and normal operation restored.  ;

I 3 l With the conputer out of service, the linear heat rate surveillance was nonitored in  ;

- i 4 g accordance with Technical Specification 4.2.1.2 utilizing the excore detector systen. ;

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