ML19254F500

LER 79-041/03L-0:on 791004,after Control Rod Bank D Was Withdrawn Several Steps,Analog Rod Position Indicators Demonstrated All Rods within +/- 5 Steps of Each Other. Caused by Instrument Drift.Indicators Recalibr

ML19254F500
Person / Time
Site:	Beaver Valley
Issue date:	11/01/1979
From:	Werling J DUQUESNE LIGHT CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19254F497	List: ML19254F496 ML19254F500
References
LER-79-041-03L, LER-79-41-3L, NUDOCS 7911090540
Download: ML19254F500 (1)

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, NRC PORM 366 U. S. P/ JCLE AR REGULATORY COMMISSION mm LICENSEE EVENT REPORT CONTROL BLOCK: l l l l l l lh (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION) l l 3

o 4 9 l P l UCENSEE A l B COOg lV l S l 1 l@l to tS 0 l0 l- l UCENst0 l0 mi,ueEM l0 l 0 l0 l- l0 l 02$ l@l4 2e l1 l1 l1TvPE ucENSE (140l@lsi car se @

CON *7 IIIII 7 8 1"Rc M

L l@l 0 l 5 OOCK 68 l CETlNUMS 010 ER l 31363 l 469 @lEVENT II 010l DATE 4l 7l 91@l1 34 75 l 1DATE hEPORT l 0 l 180l 7 l 9 l@)

EVENT CESCRIPTION AND PROBA8LE CONSEQUENCES h o :; [At 0700 hours0.0081 days <br />0.194 hours <br />0.00116 weeks <br />2.6635e-4 months <br /> Control Rod Bank D was withdrawn several steps to a demand position ofl C 1212 steps. At 0730 hours0.00845 days <br />0.203 hours <br />0.00121 weeks <br />2.77765e-4 months <br />, the Analog Rod Position Indicators were indicating all of [

O 4 Ithe Bank D rods were within +/- 5 steps of each other, although 5 of the Bank D rodsl O s twere slightly less than the required 200 steps. Movable incore detectors were used [

O 6 fto determine that no misalignment of the rods in Bank D existed. Repetitive. The f I'5Til lhealth and safety of the ceneral oublic were not ieopardized as the rody were not I I

o a Inisaliened.

OCE COO $ C E COMPONENT CODE SUSCODE $ E O 9 lR l B lh W@ W@ lI lN l S l T l R l U l@ y@ l Z l@ 20 e e iO si i2 i3 is i9 SEQUENTIAL OCCURRENCE REPORT REVISION EVENT YEAR REPORT %. CCOE TYPE NO.

LER/Ro

@ ,RE g l287l229l {) l 0l4 l 1 l 24 y

27 l0l3l 28 29 lL l 30 l--.)

31 l0 l 32

, 23 26 N ACT C 0 P T M TH HOURS 22 SE i FOR 8. SU E* MANUFAC RER lE 33 l@lZ34 l@ l35 Zl@ W@ l 010 0l0l g@ lY]g J @

36 37 40 el 42 43 lM 44 l0 { 3 l547l@

CAUSE DESCRIPTION AND CORRECTIVE ACTIONS h ITT6 l IThe incident resulted from indication instrument drift. The indicators were l

@ Irecalibrated and returned to service. A channel check verified all rod position I indicators were within ti.s allowable 12 steps of the demand position. I i 7 I

fiTT1 I I

i 4 I 9 so ST U %PCWER OTHER STAWS S O EH OISCOVERY DESCRIPTION i 5 l E !@ l0 l 4 l 7 l@[ F/A l W @l Operator observation l f s ey:TY Co$ TENT RELEASED OF RELEASE AMOUnr/ OF ACTivlTY LOCATION OF RELEASE W We 9 h [2,j@ n N/A l l N/A l 10 44 as so PER$0NNEL EXPCSURES NUM6ER TYPE DESCRIPTION ITlT) l 0 l 0 l Ojhl Z l@l N/A l

,ER So~~ E aN,UR'iE S NuMeER CESCRiPriONh E 10l0l01@l 8 9 12 N/A -

[ t 3 ) 80 l

7 li LOSS OF on CAU.CE TO FACILITY -) [. (

TYPE DE SCRIPTION

@ W@l F S 9 to N/A 80 I RIPTION

@ SSUED 7 8 9 W @l10 OE N/A

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I 68 69 lllllllllllIl5 80 5

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.412-643-1258  ?

NAME OF PREPARER

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