05000336/LER-1979-031-03, /03L-0:on 790930,control Element Assembly Motion Inhibit Circuit Declared Inoperable Following Loss of Metrascope Indication of Control Element Assembly Position. Caused by Metrascope Component Failure

/03L-0:on 790930,control Element Assembly Motion Inhibit Circuit Declared Inoperable Following Loss of Metrascope Indication of Control Element Assembly Position. Caused by Metrascope Component Failure

ML19254E511
Person / Time
Site:	Millstone
Issue date:	10/25/1979
From:	Bates R NORTHEAST UTILITIES
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19254E498	List: 05000336/LER-1979-030-03, /03L-0:on 790929,engineered Safety Feature Channel a Sensor Cabinet Trip Bistables All Tripped Due to Loss of Power.Caused by Failed Overvoltage Protector on Channel A-15 Volt Power Supply,Causing Fuse to Blow.Parts Replaced 05000336/LER-1979-031-03, /03L-0:on 790930,control Element Assembly Motion Inhibit Circuit Declared Inoperable Following Loss of Metrascope Indication of Control Element Assembly Position. Caused by Metrascope Component Failure ML19254E497
References
LER-79-031-03L, LER-79-31-3L, NUDOCS 7911010408
Download: ML19254E511 (1)

LER-1979-031, /03L-0:on 790930,control Element Assembly Motion Inhibit Circuit Declared Inoperable Following Loss of Metrascope Indication of Control Element Assembly Position. Caused by Metrascope Component Failure

Event date:
Report date:
3361979031R03 - NRC Website

text

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HEPOa T DAT E C0 EVENT DESCHIPTION AND PRO 9ABLE CONSEOUENCES h 1 During routine operations, the CEA Motion Inhibit (CMI) circuit was declared I

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g with technical specifications, section 3.1.3.1.b all CEA's were maintained fully l

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Total time out of

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l The faulty part, an operational amplifier (UA747-14 pin chip) in the clock-amplifier i

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,,,3, ; The requirements of Technical Specification 3.1.3.3 for CEA position were complied

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