05000318/LER-1979-016-03, /03L-0 on 790520:while Inserting Group 5 Control Element Assemblies,Cea 36 Dropped to Bottom of Core.Caused by Spike in 15 Volt Power Supply.Design Mod to Be Installed During Next Refueling Outage

/03L-0 on 790520:while Inserting Group 5 Control Element Assemblies,Cea 36 Dropped to Bottom of Core.Caused by Spike in 15 Volt Power Supply.Design Mod to Be Installed During Next Refueling Outage

ML19270G039
Person / Time
Site:	Calvert Cliffs
Issue date:	05/25/1979
From:	Davis S, Miernicki M BALTIMORE GAS & ELECTRIC CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19270G034	List: 05000318/LER-1979-016, Forwards LER 79-016/03L-0 05000318/LER-1979-016-03, /03L-0 on 790520:while Inserting Group 5 Control Element Assemblies,Cea 36 Dropped to Bottom of Core.Caused by Spike in 15 Volt Power Supply.Design Mod to Be Installed During Next Refueling Outage
References
LER-79-016-03L-01, LER-79-16-3L-1, NUDOCS 7906010207
Download: ML19270G039 (1)

LER-1979-016, /03L-0 on 790520:while Inserting Group 5 Control Element Assemblies,Cea 36 Dropped to Bottom of Core.Caused by Spike in 15 Volt Power Supply.Design Mod to Be Installed During Next Refueling Outage

Event date:
Report date:
3181979016R03 - NRC Website

text

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8 60 61 DOCK ET NUYBER 68 69 EVENT CATE 74 75 HEPORT DATE 50 EVENT DESCRIPTION AND PROBABLE CONSEGUENCES h At 1142 while insertino aroun 5 control eierent assemblies (CEA's), CEA 36 I

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drocoed to the botton of the core.

In accordance wi th T.S. 3.1.3.1.f, i

I reactor cower was reduced to less than 70% at 1222.

At 1242 CEA 36 was l

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withdrawn and realigned with its grouo.

LER 78-48 (U-1) and 79-12 (U-2) l o

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33 34 3b 37 40 43 42 43 44 47 CAUSE DESCRIPTION AND CCARECTIVE ACTIONS h l The droceed rod is assumed to be the result of a soike in the 15 volt oower i

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l next refuelina outage.

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