ML19242B209

LER 79-031/01X-0 on 790731:undervoltage Circuitry A-4 Logic Would Not Initiate & 15-volt Power Supplies to a & B Actuation Drawers Were Found de-energized.Cause & Corrective Action Under Investigation

ML19242B209
Person / Time
Site:	Calvert Cliffs
Issue date:	08/01/1979
From:	Harold Denton BALTIMORE GAS & ELECTRIC CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
LER-79-031-01X, LER-79-31-1X, NUDOCS 7908070678
Download: ML19242B209 (2)

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I I LER /9-31/lX DOCKET NO. 50-317 EVI.NT DATE 07-31-79 REPORT DATE 08-01-79 AT TACliMENT EVENT DESCRIPTION /ND PROBTBLE CONSEOUENCES: (CONTINUE D) by 3:00 p.m.

As a consecuence of these power supplies being de-energized, the "A" and "B" UV logic would not have actuated in the event an initiating signal had occurred.

Testing had been perforced at 0600 the same r'orning in which the UV "A"-4 logic was actuated; it is, therefore, assured that the de-energization occurred within the 7!3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> period prior to the discovery of the event at 1.30 p.m.

This is not a repetitive event.

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