ML19270F459

LER 79-002/03L-0 on 790116:following Return to sub-critical Conditions,Investigations Showed Faulty Position Indication for Control Element Assembly 63,indicating About 6 Steps High.Caused by Position Indication Unit Drift

ML19270F459
Person / Time
Site:	Millstone
Issue date:	02/08/1979
From:	Bates R NORTHEAST UTILITIES
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19270F458	List: ML19270F457 ML19270F459
References
LER-79-002-03L, LER-79-2-3L, NUDOCS 7902130130
Download: ML19270F459 (1)

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. L) LVE NT OATE _74 75 REFORT DAf t t!G EvrNT oESCnmTioN AND Pnob AGLE CONSEoVENcES h o 2] 1 Surveillance testinsdurinq reactor startup revealed _the CEA thtion Inhibit (CMI) I

- interlock did not function properly. Followina a return to sub-critical conditions l

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Io la1 L investigations showed faulty position indication for CEA 63, indicating about 6 ,

steps high, exceeding the limits of technical specifications Section 3.1.3.3.  ;

With the position indication for CEA 63 corrected and the CMI functioning properly,,

the reactor startup was resu-'ed.

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