ML19209C030

LER 79-033/03L-0:790907,high Power & Thermal Power Low Pressure pre-trip & Trip Alarms Received on Reactor Protection Sys.Causes Unknown.Possibly Due to Moist or Dirty Detector Cables

ML19209C030
Person / Time
Site:	Calvert Cliffs
Issue date:	10/08/1979
From:	Davis S, Rizzo P BALTIMORE GAS & ELECTRIC CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19209C026	List: ML19209C030
References
LER-79-033-03L, LER-79-33-3L, NUDOCS 7910110415
Download: ML19209C030 (1)

Text

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D ATE 80 EVENT DESCRIPTION AND PROBABLE CONSEQUENCES h o 2 l At 1740 the coerator started receivino hiOh power and thermal cower / low oressure I o 3 l (TM/LP) are-trips and trip alams on reactor protection system (RPS), Channel C. l l Channel C high power and TM/LP trip units were bypassed per T.S.3.3.1.1. for I o 4 o s I troubleshooting. The trip units were returned to service at 0940 on 9/8/79. l o s l The three redundant channels remained operable during the event. This has not l

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o 7 l been determined to be a recetitive event.

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i o l Symptoms above are sporP.dic. Linear power range detector 1-NE-007 subchannel l

, , signals were found to be noisy. Suspect dirty or moist detector cables. ?iainten- i ance Reouest No. 0-79-408 records problem for further work durino the refuelino

, ,  ; outaae commencino October,1979.  ;

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