ML19253A838

LER 79-024/03L-0:on 790802,reactor Protection Sys Channel D Trips for Thermal Margin/Low Pressure & Local Power Density Failed in Tripped Condition.Caused by Failed multiplier- Divider Computation Module.Module Replaced & Svc Restored

ML19253A838
Person / Time
Site:	Millstone
Issue date:	08/31/1979
From:	Bates R NORTHEAST UTILITIES
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19253A835	List: ML19253A834 ML19253A838
References
LER-79-024-03L-01, LER-79-24-3L-1, NUDOCS 7909110503
Download: ML19253A838 (1)

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i 2 l During routine plant, operation, the Reactor Protection System Chantel D trins for i

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3 l thermal margin / low pressure and local power density failed in the tripped condition. I j., 4 LnI cc rdance with technical specifications Section 3.3.1.1, Table 3.3-1, Action i F- 5 g 2.b, the trips for thermal margin / low pressure, local power density and power level I

,, g [ high were bypassed on Channel 0 and operation continued. t 1 l7 l I i a i I 8 9 0 S Y S T E *.' ,'; CAUSE CO*.' P. VALVE CO?E .s! SUBCODE CO'.*PC'.E N T CODE SU3CCOE SU3C03 E oo 8 9 I II AJ 8 LfJ@ LrJ @ Li l tl i s l T l a l u l8 LyJ@ IlJ @

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