05000318/LER-1979-030-03, /03L-0:on 790805,control Element Assemblies 6,7, 49,51 & 53 Failed to Initiate Motion Inhibit Function. Caused by Drifting of Motion Inhibit Setpoint Voltage Levels.Setpoints Will Be Reduced

/03L-0:on 790805,control Element Assemblies 6,7, 49,51 & 53 Failed to Initiate Motion Inhibit Function. Caused by Drifting of Motion Inhibit Setpoint Voltage Levels.Setpoints Will Be Reduced

ML19253B057
Person / Time
Site:	Calvert Cliffs
Issue date:	08/31/1979
From:	Heibel R, Rizzo P BALTIMORE GAS & ELECTRIC CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19253B054	List: 05000318/LER-1979-030, Forwards LER 79-030/03L-0 05000318/LER-1979-030-03, /03L-0:on 790805,control Element Assemblies 6,7, 49,51 & 53 Failed to Initiate Motion Inhibit Function. Caused by Drifting of Motion Inhibit Setpoint Voltage Levels.Setpoints Will Be Reduced
References
LER-79-030-03L, LER-79-30-3L, NUDOCS 7909140430
Download: ML19253B057 (1)

LER-1979-030, /03L-0:on 790805,control Element Assemblies 6,7, 49,51 & 53 Failed to Initiate Motion Inhibit Function. Caused by Drifting of Motion Inhibit Setpoint Voltage Levels.Setpoints Will Be Reduced

Event date:
Report date:
3181979030R03 - NRC Website

text

NnC FORM 366 U. S. NUCLE AR REGULATORY COMMISSION (17/8 LICENSEE EVENT REPORT CONTROL BLOCK: l l

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8 60 61 DOCK ET NUMBER 68 69 EVENT DATE 74 75 REPORT DATE 80 EVENT OESCRIPTION AND PRO 9 ABLE CONSEQUENCES h o 2 L At 0250 durino the nerformance of a routine surveillance test. it was discovered I

o 3 l that Control Element Assemblies (CEA's) 6, 7, 49, 51 and 53 failed to initiate a I

CEA l'oition Inhibit (CMI) function when these CEAs deviated from their arouos by 1

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Lo s I creater than 7.5 inches. The CEAs were fully withdrawn and the CEA drive system I

o e I was raintained off as recuired by T.S.3.1.3.1. until the CEA circuit was reoaired I

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LER 79-25 (U-2) describes a similar occurrence.

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The setroints will be 3 7 l reduced as previcusly described in LER 79-25/3L for plant decket no. 50-318.

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