05000293/LER-1979-027-01, /01T-0 on 790727:reactor Scram Occurred as Result of Loss of All Offsite Power.Caused by Lightning Striking Offsite Distribution Lines.Resulting Backflash Caused High Speed Relay Operation for Line to Ground Fault

/01T-0 on 790727:reactor Scram Occurred as Result of Loss of All Offsite Power.Caused by Lightning Striking Offsite Distribution Lines.Resulting Backflash Caused High Speed Relay Operation for Line to Ground Fault

ML19207A405
Person / Time
Site:	Pilgrim
Issue date:	08/10/1979
From:	Fulton J BOSTON EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19207A404	List: 05000293/LER-1979-027, Forwards LER 79-027/01T-0 05000293/LER-1979-027-01, /01T-0 on 790727:reactor Scram Occurred as Result of Loss of All Offsite Power.Caused by Lightning Striking Offsite Distribution Lines.Resulting Backflash Caused High Speed Relay Operation for Line to Ground Fault
References
LER-79-027-01T, LER-79-27-1T, NUDOCS 7908170423
Download: ML19207A405 (1)

LER-1979-027, /01T-0 on 790727:reactor Scram Occurred as Result of Loss of All Offsite Power.Caused by Lightning Striking Offsite Distribution Lines.Resulting Backflash Caused High Speed Relay Operation for Line to Ground Fault

Event date:
Report date:
2931979027R01 - NRC Website

text

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7 l On.luly 27, 1979 at 0101 hours0.00117 days <br />0.0281 hours <br />1.669974e-4 weeks <br />3.84305e-5 months <br />. a reactor scram occurred as a result of a loss of all o[f -

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[ site power. The Diesel Generators fune oned as required and'asqu ned emergency loads.

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{ the reactor to a shutdown condition.

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~}T]l The cause of this event was lightning utriking the of f-site distribution lines causing j

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j 8 S 11 12 13 WERSONNT L INJUHIE5 80 NUUD E R DESCRIPTION 41 E 1o 1010 J@l N.A.

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