ML19275A285

LER 79-078/03L-0:on 790828,refueling Water Tank Level Indicator Read 2.7% Less than Computer Point Indication. Caused by Current Loop Opening When Indicator Head Was Lifted.Resistor Location Corrected & Indicator Recalibr

ML19275A285
Person / Time
Site:	Arkansas Nuclear
Issue date:	09/26/1979
From:	Shively C ARKANSAS POWER & LIGHT CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML19275A279	List: ML19275A278 ML19275A285 ML19275A286
References
LER-79-078-03L, LER-79-78-3L, NUDOCS 7910030460
Download: ML19275A285 (1)

Text

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60 6l DOCaffNywegn edi EVENT DArg to it Hp poe4 T D ATE 80 EVENT DESCRIPTION AND PROB ADLE CONSEQUENCES O'o FETT', I During Mode 1 operation, it was discovered that the Refueling h'ater Tank i ioi2i Level indicator, 2LI-56-, was reading 2.7% less than the computer point l A Iindication. h' hen the indicator was removed from service for recalibra- J In i s t i tion, a RAS trip sinnal was initiated placing the Channel "B" PPS in a  !

lo I61 I trinned condition. The remainine PPS channels remained operable. There i lo Iil I have been no similar occurrences. Reportable per T.S.6.9.1.9b. I O e l l

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se CAusE des:RmTioN Ano CoRREC flVE ACTIONS ii Io i iInvestigation revealed that the trip was caused by the current loop i ITTTl I opening when the indicator lead was lifted. A previous modification to i u.,p._j1the SIGMA indicator had removed a parallel resistor in the PPS rather 1

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. Icorrected, the indicator recalibrated, and the PPS channel returned to ,

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' ' 'o u..., ,o N AME OF PREPARER Chris N. Shively ,,,g, , 501/968-2519