05000368/LER-1979-078-03, /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

/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: 05000368/LER-1979-078-03, /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 05000368/LER-1979-079-03, /03L-0:on 790904,containment Bldg Sump Level Indicator Was Inoperable.Caused by Loss of Power Due to Power Supply Being Inadvertently Switched Off.Power Supply Was re-energized within 13-h & Caution Cord Attached ML19275A278
References
LER-79-078-03L, LER-79-78-3L, NUDOCS 7910030460
Download: ML19275A285 (1)

LER-1979-078, /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

Event date:
Report date:
3681979078R03 - NRC Website

text

NRC FORM %6 U 5 NUCLE AR REGULATORY COMMIS$10N 87 77)

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60 6l DOCaffNywegn edi 69 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.

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