ML19319B880

LER 78-057/01T-0:on 780607,found That Memory Logic,Giving Offsite Power Protection,Can Be Defeated.Caused by Procedure Deficiency.Procedure Modified Disallowing Backfeeding Feeder Bus from Essential Bus.Design Mod Being Investigated

ML19319B880
Person / Time
Site:	Davis Besse
Issue date:	06/20/1978
From:	Albert J TOLEDO EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML19319B877	List: ML19319B876 ML19319B880
References
LER-78-057-01T, LER-78-57-1T, NUDOCS 8001280735
Download: ML19319B880 (1)

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[j~E] l It van discoverud that the memor/ J ogi.c which gives thn-loss of of fnite poteue orotec-The fcc. der breaker could have banin j g l tiua could hu defeated under certein operations.

to supply the annential bus and back __l .

g g,}nually closnd tn allow the diet;el gennenLur TF the esnunLial hu a was backfeeding ]

gg l Leed the fneduc 'ous throur,h the feeder breaker.

SFAS ac runt.iuu. the SFAS snnuencer would ,n.:t j PW} [,the. feuder bus sir.itltaneously vi r.h att levels were actuated, j

[p'lT} (Start sud the loads tmuld be imediately loaded as the incident l

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