05000336/LER-1979-001-03, /03L-0 on 790105:during Normal Operation,Failure of Inverter 4 Interrupted 120V Vital AC Power to Channel D Components.Inverter Malfunction Caused by Failure of Several Capacitors (C1) & Oscillator Board (SC1-PL-1163)

/03L-0 on 790105:during Normal Operation,Failure of Inverter 4 Interrupted 120V Vital AC Power to Channel D Components.Inverter Malfunction Caused by Failure of Several Capacitors (C1) & Oscillator Board (SC1-PL-1163)

ML19261A705
Person / Time
Site:	Millstone
Issue date:	02/02/1979
From:	Bates R NORTHEAST UTILITIES
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19261A702	List: 05000336/LER-1979-001, Forwards LER 79-001/03L-0 05000336/LER-1979-001-03, /03L-0 on 790105:during Normal Operation,Failure of Inverter 4 Interrupted 120V Vital AC Power to Channel D Components.Inverter Malfunction Caused by Failure of Several Capacitors (C1) & Oscillator Board (SC1-PL-1163)
References
LER-79-001-03L, LER-79-1-3L, NUDOCS 7902060296
Download: ML19261A705 (1)

LER-1979-001, /03L-0 on 790105:during Normal Operation,Failure of Inverter 4 Interrupted 120V Vital AC Power to Channel D Components.Inverter Malfunction Caused by Failure of Several Capacitors (C1) & Oscillator Board (SC1-PL-1163)

Event date:
Report date:
3361979001R03 - NRC Website

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8 60 61 OOCKET NUMBER 68 63 EVENT DATE 14 75 REPORT DATE 80 EVENT DESCRIPTION AND PROBAOLE CONSEQUENCES h l During routine power operation, the failure of inverter No. 4 resulted in an Ia 2

The l interruption of 120 volt vital AC power to channel D RPS and ESAS cc -ponents.

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l channel D RPS trips for High Power, local Power Density, High Pressurizer Pressure g

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I and High Containment Pressure, and the ESAS trip for High Containment Pressure were

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disabled, were subsequently inhibited and operation continued in accorJance with _

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3 l Technical Specifications Section 3.3.1.1, Table 3.3-1, Action 2b, and action 3.3.2.1, ia 7

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Solid State Controls, Inc.; Model SV12150/TS-150NB.

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I in the channel D RPS and ESAS cabinets which were replaced and operation continued.

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