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{{#Wiki_filter:e!'CCELERATEDDISTRIBUTIONDEMONRATIONSYSTEM'EGULATORYINFORMATIONDISTRIBUTIONSYSTEM(RIDS)ACCESSIONNBR:9112170532DOC.DATE:91/12/11NOTARIZED:NODOCKETFACIL:50-244RobertEmmetGinnaNuclearPlant,Unit1,RochesterG05000244AUTH.NAME'AUTHORAFFILIATIONBACKUS,W.H.RochesterGas&ElectricCorp.MECREDY,R.C.RochesterGas&ElectricCorp..RECIP.NAMERECIPIENTAFFILIATION*
{{#Wiki_filter:e!'CCELERATED DISTRIBUTION DEMONRATION SYSTEM'EGULATORY INFORMATION DISTRIBUTION SYSTEM(RIDS)ACCESSION NBR:9112170532 DOC.DATE:
91/12/11NOTARIZED:
NODOCKETFACIL:50-244 RobertEmmetGinnaNuclearPlant,Unit1,Rochester G05000244AUTH.NAME'AUTHORAFFILIATION BACKUS,W.H.
Rochester Gas&ElectricCorp.MECREDY,R.C.
Rochester Gas&ElectricCorp..RECIP.NAME RECIPIENT AFFILIATION
*


==SUBJECT:==
==SUBJECT:==
LER91-009-00:on911111,steamgeneratorfeedwaterisolations'ccurredonbothsteamgenerators.Causedbyperturbationsof~advanceddigitalfeedwatercontrolsys.Feedwaterregulatingvalvesmanuallycontrolled.W/911211ltr.DISTRIBUTIONCODE:IE22TCOPIESRECEIVED:LTRgENCLgSIZE:i(7TITLE:50.73/50.9LicenseeEventReport(LER),IncidentRpt,etc.DNOTES:LicenseExpdateinaccordancewith10CFR2,2.109(9/19/72).05000244ARECIPIENTIDCODE/NAMEPD1-3LAJOHNSON,AINTERNAL:ACNWAEOD/DSP/TPAB.NRR/DET/ECMB9HNRR/DLPQ/LHFB10NRR/DOEA/OEABNRR/DST/SELB8DNRR~ST/SPLB8DlN1LE01EXTERNAL:EG&GBRYCE,J.HNRCPDRNSICPOORE,W.COPIESLTTRENCL111122111111111111111'1331111RECIPIENTIDCODE/NAMEPD1-3PDAEOD/DOAAEOD/ROAB/DSPNRR/DET/EMEB7ENRR/DLPQ/LPEB10NRR/DREP/PRPB11NRR/DST/SICB8H3NRR/DST/SRXB8ERES/DSIR/EIBLSTLOBBYWARDNSICMURPHY,G.ANUDOCSFULLTXTCOPIESLTTRENCL1111221.11122111111111111DDDNOTETOALL"RIDS'ECIPIENTS:DDPLEASEHELPUSTOREDUCEi'i'ASTE!CONTACTTHEDOCUlii!EiiTCONTROLDESK,ROOliIPl-37(EXT.2M79)TQLILIih!INAl'EYOURNAiIF.FROii1DISTRIBUTIONLISTSFORDOCUiiIENTSYOUDON'TNEED!FULLTEXTCONVERSIONREQUIREDTOTALNUMBEROFCOPIESREQUIRED'TTR31ENCL31 ake0 ROCHESTERGASANDELECTRICCORPORATIONns~~~'w~~st,ss@ssee9EASTAVENUE,ROCHESTERN.K14649-0001",ROBERTCMECREDYVicePsesidensCfnnns'ueiessPsodueBunTELEPiSONEAREACUE7s65462700December11,1991U.S.NuclearRegulatoryCommissionDocumentControlDeskWashington,DC20555
LER91-009-00:on 911111,steam generator feedwater isolations'ccurred onbothsteamgenerators.
Causedbyperturbations of~advanceddigitalfeedwater controlsys.Feedwater regulating valvesmanuallycontrolled.W/911211 ltr.DISTRIBUTION CODE:IE22TCOPIESRECEIVED:LTR gENCLgSIZE:i(7TITLE:50.73/50.9 LicenseeEventReport(LER),IncidentRpt,etc.DNOTES:License Expdateinaccordance with10CFR2,2.109(9/19/72).
05000244ARECIPIENT IDCODE/NAME PD1-3LAJOHNSON,A INTERNAL:
ACNWAEOD/DSP/TPAB.NRR/DET/ECMB 9HNRR/DLPQ/LHFB10 NRR/DOEA/OEAB NRR/DST/SELB 8DNRR~ST/SPLB8DlN1LE01EXTERNAL:
EG&GBRYCE,J.H NRCPDRNSICPOORE,W.COPIESLTTRENCL111122111111111111111'1331111RECIPIENT IDCODE/NAME PD1-3PDAEOD/DOAAEOD/ROAB/DS PNRR/DET/EMEB 7ENRR/DLPQ/LPEB10 NRR/DREP/PRPB11 NRR/DST/SICB8H3 NRR/DST/SRXB 8ERES/DSIR/EIB LSTLOBBYWARDNSICMURPHY,G.A NUDOCSFULLTXTCOPIESLTTRENCL1111221.11122111111111111DDDNOTETOALL"RIDS'ECIPIENTS:
DDPLEASEHELPUSTOREDUCEi'i'ASTE!
CONTACTTHEDOCUlii!EiiT CONTROLDESK,ROOliIPl-37(EXT.2M79)TQLILIih!INAl'EYOURNAiIF.FROii1DISTRIBUTION LISTSFORDOCUiiIENTS YOUDON'TNEED!FULLTEXTCONVERSION REQUIREDTOTALNUMBEROFCOPIESREQUIRED'TTR 31ENCL31 ake0 ROCHESTER GASANDELECTRICCORPORATION ns~~~'w~~st,ss@ssee9EASTAVENUE,ROCHESTER N.K14649-0001
",ROBERTCMECREDYVicePsesidens Cfnnns'ueiessPsodueBun TELEPiSONE AREACUE7s65462700December11,1991U.S.NuclearRegulatory Commission DocumentControlDeskWashington, DC20555


==Subject:==
==Subject:==
LER91-009,AutomaticFeedwaterControlPerturbations,DueTo'lectromagneticNoiseSpikesFromUnrelatedRelayActuation,CausedSteamGeneratorFeedwaterIsolationonHighLevelR.E.GinnaNuclearPowerPlantDocketNo.50-244Inaccordancewith10CFR50.73,LicenseeEventReportSystem,item.(a)(2)(iv),whichrequiresareportof,"anyeventorconditionthatresultedinmanualorautomaticactuationofanyEngineeredSafetyFeature(ESF),includingtheReactorProtectionSystem(RPS)",theattachedEventReportLER91-009isherebysubmitted.Thiseventhasinnowayaffectedthepublic'shealthandsafety.Verytrulyyours,RobertC.MecredyxcoU.S.NuclearRegulatoryCommissionRegionI475AllendaleRoadKingofPrussia,PA19406GinnaUSNRCSeniorResidentInspector 0I NACtera000ISASIUCENSEEEVENTREPORT(LER)U*NUOLCARRICULATQR'vcoeal~At<<IIOVIDOMSNO,SIMOIOrrlxSIRISI/Sr/ttfACILITYNA<<rtIllR.E.GinnaNuclearPowerPlantDOCXITNVMIIRQlo6ooo244>as09'"AutomaticFeedwaterControlPerturbations,DueToElectromagneticNoise.SpikesFromUnrelatedRelaActuationmusedSteamGeneratorFeedwaterIsolationonHihLvelIVINTOATIISILIRNVMICRIMAltORTOATSITIOTHI1fACILI'TillINVOLVIOQlMONTrrOAYYCARYCAJI~IOVIrlrl*L")AIVRIQrrNVMIIArlerrreIAMONTHOAYYCARfACrLIT'rHAMILOOCXITNVMIIRISI0600091910090012119106000OtC1ATINCMOOCIIILIYIL098~i>rio,.W)Wi$~g'.+THII1lfORTIISVSMITTCOtURSVANTTS0.<<0SIII00.<<004IIIIIIIS0.0004IIIIIIISS.IM4IIIIIMISIACI4IIIIIHISO.IMle)llllrlSS.IMirl,MMlrlllIMMNIQIM.TSUIQII4M.TIleIQIIIIM.TSNIQIIX4M.TSVIQIlleIM.TS4IQIIrlM.T04IQllrllM.TSNIQIIHXIIAIM.TSNIQ)lralltlM.TSIIIQllel0THI1IOVI1SirINTSOf10Cf1f<ICrrreieeeererereerarle<<eeeeNIIITLTllel0THc1/S<<ee<<V4AAreerr~erierrre4Tr<<LNRCfareLICINSIICONTACTtO1THISLIRlltlNAMtTILltHONINVMSIRWesleyH.BackusARIACOOtTechnicalAssistanttotherationsManaer315524-4446COM<<LITCONILINCf01IACHCOM<<ONINTfAILURCOtICRIIIOINTHISRltORTllllCAVStSYSTSMCOMtOHINTMANVfAOTURIRAPrr"""~">""+CAVSISYSTSMCOMtONCNTTONtROI.5":ij>S.<~,~86:'jjpQ%.(@~kgMANVfAOTURINltORTASLTONtROSe~rg~@4~@IVtfLtMINTALRtt01TIXtlCTIOIIIIYCtlllfer,reer<<rraIX<</CTIOSVSMISSIONOATIINOLIITAAOTII<<erraIrofireea,I~..rterer<<errNfINaeer<<vrre<<rrrtrteerarre<<ewll~ICXflCTIOLvll<<ISCIONOATII'IIIMOHTHCAYYIAROnNovember11,1991atapproximately1214EST,withthereactoratapproximately98%fullpower,steamgeneratorfeedwaterisolationsoccurredonbothsteamgenerators.Thesefeedwaterisolationswerecausedbyperturbationsoftheadvanceddigitalfeedwatercontrolsystemwhichincreasedfeedwaterflowtot1'teamgenerators.Immediateoperatoractionwastomanuallycontrolthefeedwaterregulatingvalvestoreducesteamgeneratorlevelsandstabilizetheplant.Theunderlyingcauseoftheeventwasdeterminedtobeelectro-magneticnoisespikesaffectingtheadvanceddigitalfeedwatercontrolsystem.Correctiveactiontakenwastomodifyspecificrelaycircuitsthatwerecausingthesespikes.NACfaaSMIIASI Il IIACSeeMI000ILICENSEEEVENTREPORT(LER)TEXTCONTINUATIONV.I.IIVCLCAAAlOVLATOAV<<OMMHNISI/AtPAOVKOOMAMll%0&I04a>>tiACSll)IWSI'ACILITYIIAMCIIIOOCKETIIVM~EAl11LlllIIVMOIIIIII'NOVINT<Al,'ttV4%8UA~AOIIIIR.E.GinnaNuclearPowerPlantTQTTIII~~%MA~.~y480OAVNACAnil~'ilIITI24491-009-0002or0PRE-EVENTPLANTCONDITIONSTheplantwasatapproximately98%steadystatereactorpowerwithnomajoractivitiesinprogress.TheMaintenanceDepartmentwasperformingtroubleshooting,todeterminethesourceofelectromagneticnoise,spikesintheAdvancedDigitalFeedwaterControlSystem(ADFCS).Thetroubleshoot-ingwasbeingperformedundertheguidanceofWorkOrderpackagef9122181.Unexplainedelectromagnetic'noisespikeproblemswereidentifiedpreviouslyascoincidingwiththestartofthedieselfirepump,andwhichhadminoreffectontheADFCScontrolfunctions.TheADFCSwasinstalledduringthe1991"AnnualRefuelingandMaintenanceOutage.TheseelectromagneticnoisespikeswerefirstnoticedonJune4,1991,whenaminorfeedwaterperturbationoccurred,followingadieselfirepumpstart.SinceJune4,spikeshaveoccurredalmosteverytimethediesel'firepumphasstarted.TheADFCS.hashandledspikeswithnonoticeablefeedwaterperturbations,exceptfortwo(2)occasions.Theseoccasions,thefirstonJune4,1991andthesecondonSeptember13,1991,werehandledbytheADFCSinautomaticandnooperatoractionwasrequired.Therehasbeenanongoingsearchforthepossiblesourceofthiselectromagneticnoisespikesothatitcouldbecorrected.Aspartofthisongoingsearch,theElectricalEngineeringDepartmentevaluatedtheircabletraydatabaseandidentifiedcircuitE174asapossiblesource.CircuitE174isthe125VoltDCpowerfeedtothefirerelaypanelandsharessomecabletrayswithADFCSinputcables,mostnotably,thefeedwaterheaderpressureinputstoADFCS'P501andP502).'IACAOAMAAAital  
LER91-009,Automatic Feedwater ControlPerturbations, DueTo'lectromagnetic NoiseSpikesFromUnrelated RelayActuation, CausedSteamGenerator Feedwater Isolation onHighLevelR.E.GinnaNuclearPowerPlantDocketNo.50-244Inaccordance with10CFR50.73,LicenseeEventReportSystem,item.(a)(2)(iv),
whichrequiresareportof,"anyeventorcondition thatresultedinmanualorautomatic actuation ofanyEngineered SafetyFeature(ESF),including theReactorProtection System(RPS)",theattachedEventReportLER91-009isherebysubmitted.
Thiseventhasinnowayaffectedthepublic'shealthandsafety.Verytrulyyours,RobertC.MecredyxcoU.S.NuclearRegulatory Commission RegionI475Allendale RoadKingofPrussia,PA19406GinnaUSNRCSeniorResidentInspector 0I NACtera000ISASIUCENSEEEVENTREPORT(LER)U*NUOLCAR RICULATQR'v coeal~At<<IIOVID OMSNO,SIMOIOrrlxSIRISI/Sr/ttfACILITYNA<<rtIllR.E.GinnaNuclearPowerPlantDOCXITNVMIIRQlo6ooo244>as09'"Automatic Feedwater ControlPerturbations, DueToElectromagnetic Noise.SpikesFromUnrelated RelaActuation musedSteamGenerator Feedwater Isolation onHihLvelIVINTOATIISILIRNVMICRIMAltORTOATSITIOTHI1fACILI'Till INVOLVIOQlMONTrrOAYYCARYCAJI~IOVIrlrl*L
")AIVRIQrrNVMIIArlerrreIAMONTHOAYYCARfACrLIT'rHAMILOOCXITNVMIIRISI 0600091910090012119106000OtC1ATINCMOOCIIILIYIL098~i>rio,.W)Wi$~g'.+THII1lfORTIISVSMITTCO tURSVANTTS0.<<0SIII 00.<<004IIIIIIIS0.0004IIIIIII SS.IM4IIIIIMISIACI4IIIIIHISO.IMle)llllrlSS.IMirl, MMlrlllIMMNIQIM.TSUIQII4 M.TIleIQIIIIM.TSNIQIIX4 M.TSVIQIlleIM.TS4IQIIrlM.T04IQllrllM.TSNIQIIHXIIAI M.TSNIQ)lralltl M.TSIIIQllel 0THI1IOVI1SirINTSOf10Cf1f<ICrrreieeeererereerarle<<eeeeNIIITLTllel0THc1/S<<ee<<V4AAreerr~erierrre4Tr<<LNRCfareLICINSIICONTACTtO1THISLIRlltlNAMtTILltHONI NVMSIRWesleyH.BackusARIACOOtTechnical Assistant totherationsManaer315524-4446COM<<LITCONILINCf01IACHCOM<<ONINT fAILURCOtICRIIIO INTHISRltORTllllCAVStSYSTSMCOMtOHINTMANVfAOTURIRAPrr"""~">""+CAVSISYSTSMCOMtONCNT TONtROI.5":ij>S.<~,~86:
'jjpQ%.(@~kgMANVfAOTURINltORTASLTONtROSe~rg~@4~@
IVtfLtMINTALRtt01TIXtlCTIOIIIIYCtlllfer,reer<<rraIX<</CTIOSVSMISSIONOATIINOLIITAAOTII<<erraIrofireea,I~..rterer<<errNf INaeer<<vrre<<rrr trteerarre
<<ewll~ICXflCTIOLvll<<ISCIONOATII'IIIMOHTHCAYYIAROnNovember11,1991atapproximately 1214EST,withthereactoratapproximately 98%fullpower,steamgenerator feedwater isolations occurredonbothsteamgenerators.
Thesefeedwater isolations werecausedbyperturbations oftheadvanceddigitalfeedwater controlsystemwhichincreased feedwater flowtot1'teamgenerators.
Immediate operatoractionwastomanuallycontrolthefeedwater regulating valvestoreducesteamgenerator levelsandstabilize theplant.Theunderlying causeoftheeventwasdetermined tobeelectro-magneticnoisespikesaffecting theadvanceddigitalfeedwater controlsystem.Corrective actiontakenwastomodifyspecificrelaycircuitsthatwerecausingthesespikes.NACfaaSMIIASI Il IIACSeeMI000ILICENSEEEVENTREPORT(LER)TEXTCONTINUATION V.I.IIVCLCAAAlOVLATOAV
<<OMMHNISI
/AtPAOVKOOMAMll%0&I04a>>tiACSll)IWSI'ACILITYIIAMCIIIOOCKETIIVM~EAl11LlllIIVMOIIIIII'NOVINT<Al,
'ttV4%8UA~AOIIIIR.E.GinnaNuclearPowerPlantTQTTIII~~%MA~.~y480OAVNACAnil~'ilIITI24491-009-0002or0PRE-EVENT PLANTCONDITIONS Theplantwasatapproximately 98%steadystatereactorpowerwithnomajoractivities inprogress.
TheMaintenance Department wasperforming troubleshooting, todetermine thesourceofelectromagnetic noise,spikesintheAdvancedDigitalFeedwater ControlSystem(ADFCS).Thetroubleshoot-ingwasbeingperformed undertheguidanceofWorkOrderpackagef9122181.
Unexplained electromagnetic
'noisespikeproblemswereidentified previously ascoinciding withthestartofthedieselfirepump,andwhichhadminoreffectontheADFCScontrolfunctions.
TheADFCSwasinstalled duringthe1991"AnnualRefueling andMaintenance Outage.Theseelectromagnetic noisespikeswerefirstnoticedonJune4,1991,whenaminorfeedwater perturbation
: occurred, following adieselfirepumpstart.SinceJune4,spikeshaveoccurredalmosteverytimethediesel'firepumphasstarted.TheADFCS.hashandledspikeswithnonoticeable feedwater perturbations, exceptfortwo(2)occasions.
Theseoccasions, thefirstonJune4,1991andthesecondonSeptember 13,1991,werehandledbytheADFCSinautomatic andnooperatoractionwasrequired.
Therehasbeenanongoingsearchforthepossiblesourceofthiselectromagnetic noisespikesothatitcouldbecorrected.
Aspartofthisongoingsearch,theElectrical Engineering Department evaluated theircabletraydatabaseandidentified circuitE174asapossiblesource.CircuitE174isthe125VoltDCpowerfeedtothefirerelaypanelandsharessomecabletrayswithADFCSinputcables,mostnotably,thefeedwater headerpressureinputstoADFCS'P501 andP502).'IACAOAMAAAital  


NIICPe<<<<1~044II.'ICENSEEEVENTREPORTILER)TEXTCONTINUATION<<U.S.NUCLIAAAIOULAT01TCOMMITeION/AAAAOV%0OMINOTISOWIOAT)eAt1%$~III1$I'ACILITYNAMIIIIR.E.GinnaNuclearPowerPlantTQ(TIA'<<<<44NMCO4~.<<<<MMM41<<<<MNOMIC/Oral~TIIITIDOC%ITNUNMtNITIosooo244LlllNUMOl1IIIvTAA,'AQVANT<<AL1(V4<<O<<<<41<<<<4191-00900~AOIIS030'9WestinghouseElectricCorporation(themanufactureroftheADFCS)wascontactedandcouldnotexplaintheADFCSexcursionsbasedon,dataavailable.InconjunctionwiththeElectricalEngineeringDepartment,WestinghousehadpreviouslyrecommendedthattheshieldingandgroundingschemesforallADFCSinputsbechecked.TheseinputswerecheckedinAugust,1991.ThischeckindicatedthatallADFCSinputsarecorrectlyshieldedandgrounded.DESCRIPTIONOFEVENTA.DATESANDAPPROXIMATETIMESOFMAZOROCCURRENCES:00November11,1991,1214EST:EventDateandApproximateTime.November11,1991,1214EST:DiscoveryDateandApproximateTime.oNovember15,1991:CauseofEMPnoisespikeidentifiedandsuppressedtoacceptablelevels.WGBFZ:OnNovember11,1991,atapproximately1214EST,withthereactoratapproximately98%fullpower,thedieselfirepumpwasstarted,asrequiredforADFCStroubleshootingperWork.Orderf9122181.Approximatelythirty(30)secondsafterthedieselfirepumpwasstartedan"ADFCSSystemTrouble"alarm(G-22)wasreceived.TheControlRoomoperatorresponsibleforfeedwatercontrolhadpre-positionedhimselfinfrontofthe"A"and"B"S/GMainFeedwaterRegulatingValves(FRV)controlpanelpriortothestartofthedieselfirepump.~<<1CADAMTQAA<<tel  
NIICPe<<<<1~044II.'ICENSEE EVENTREPORTILER)TEXTCONTINUATION
<<U.S.NUCLIAAAIOULAT01T COMMITeION
/AAAAOV%0OMINOTISOWIOAT)eAt1%$~III1$I'ACILITY NAMIIIIR.E.GinnaNuclearPowerPlantTQ(TIA'<<<<44NMCO4~.<<<<MMM41<<<<MNOMIC/Oral~TIIITIDOC%ITNUNMtNITIosooo244LlllNUMOl1IIIvTAA,'AQVANT<<AL 1(V4<<O<<<<41<<<<4191-00900~AOIIS030'9Westinghouse ElectricCorporation (themanufacturer oftheADFCS)wascontacted andcouldnotexplaintheADFCSexcursions basedon,dataavailable.
Inconjunction withtheElectrical Engineering Department, Westinghouse hadpreviously recommended thattheshielding andgrounding schemesforallADFCSinputsbechecked.TheseinputswerecheckedinAugust,1991.Thischeckindicated thatallADFCSinputsarecorrectly shieldedandgrounded.
DESCRIPTION OFEVENTA.DATESANDAPPROXIMATE TIMESOFMAZOROCCURRENCES:
00November11,1991,1214EST:EventDateandApproximate Time.November11,1991,1214EST:Discovery DateandApproximate Time.oNovember15,1991:CauseofEMPnoisespikeidentified andsuppressed toacceptable levels.WGBFZ:OnNovember11,1991,atapproximately 1214EST,withthereactoratapproximately 98%fullpower,thedieselfirepumpwasstarted,asrequiredforADFCStroubleshooting perWork.Orderf9122181.
Approximately thirty(30)secondsafterthedieselfirepumpwasstartedan"ADFCSSystemTrouble"alarm(G-22)wasreceived.
TheControlRoomoperatorresponsible forfeedwater controlhadpre-positioned himselfinfrontofthe"A"and"B"S/GMainFeedwater Regulating Valves(FRV)controlpanelpriortothestartofthedieselfirepump.~<<1CADAMTQAA<<tel  


1IICSeam~I$4$lLICENSEEEVENTREPORTILER)TEXTCONTINUATIONV.S.IIVCLCA1AIOVLATOAYCOSSSSt%IOIIrASSAOYCOOU~IIOSI$0&IOSTIIAI1$$~ITI%$AACILITYNASISI1I-OOCKSTIIVIAOIAIllL$1NLAN$1I~ISSOUS>S<ALASYCK)UU1'UA~A4$ISIR.E.GinnaNuclearPowerPlantTQ(T/ITmewAIASS1~.~e4004HVJYACAMID~YlIIllosooo24491-009-0004or09Atthistime,theControlRoomoperatornoticedthatboththe"A"and"B"SteamGenerator(S/G)mainfeedwaterflowswerepeggedhigh.withboth"A"and"B"S/GMainFeedwaterRegulatingValvescontinuingtoopenfurther.Thecondensatelowpressureheater.bypassvalveopenedautomaticallyandthestandbycondensatepumpstartedautoma'tically(toincreasemainfeedwaterpumpsuctionpressure).MainFeedwaterpumpsuctionpressurewasdecreasingduetotheincreasedfeedwaterflowtotheS/Gs.The"A"and"B"S/GlevelscontinuedtoincreaseandbeforetheControlRoomoperatorcouldshift'theFRVstomanual,ADFCSautomaticallyshiftedtheFRVstomanual.WhiletheControlRoomoperatorwasmanuallyloweringthesetpointsfortheFRVcontrollers,tocontrolS/Glevel,thefollowingalarmsannunciatedandfeedwaterisolationo'ccurredonbothS/Gs;G-4(S/GAHILEVELCHANNELALERT67%)andG-6(S/GBHILEVELCHANNEL,ALERT67%).Immediatelyfollowingthefeedwaterisolation,thecondensateboosterpumpstrippedonhigh*pressure.Aloadde'creasewasinitiatedat10%/hourtolessentheimpactofunstableS/Glevels.MainfeedwatertotheS/Gswascontrolledinmanualinordertostopsecondarysystemoscillationsthatwereoccurringduetotheevent.DuringtheS/Glevelstabile.zation,S/Gfeedwaterisolationoccurredseveraltimes.TheS/Glevelsweresubsequentlystabilizedandmainfeedwatercontrolwasreturnedtoautomatic.Aftermainfeedwatercontrolwasreturnedtoautomatictheloaddecreasewasterminated.Totalloaddecreasewasapproximately0.54fullpowerduringtheevent.Subsequently,thecondensatelowpressureheaterbypassvalvewasclosed,thecondensateboosterpumpswererestored,andthestandbycondensatepumpwassecuredandrealignedforautomaticstandby.~~VACSOAVSSAAi$4$l  
1IICSeam~I$4$lLICENSEEEVENTREPORTILER)TEXTCONTINUATION V.S.IIVCLCA1AIOVLATOAY COSSSSt%IOII rASSAOYCOOU~IIOSI$0&IOSTIIAI1$$~ITI%$AACILITYNASISI1I-OOCKSTIIVIAOIAIllL$1NLAN$1I~ISSOUS>S<AL ASYCK)UU1'UA~A4$ISIR.E.GinnaNuclearPowerPlantTQ(T/ITmewAIASS1~.~e4004HVJYACAMID~YlIIllosooo24491-009-0004or09Atthistime,theControlRoomoperatornoticedthatboththe"A"and"B"SteamGenerator (S/G)mainfeedwater flowswerepeggedhigh.withboth"A"and"B"S/GMainFeedwater Regulating Valvescontinuing toopenfurther.Thecondensate lowpressureheater.bypassvalveopenedautomatically andthestandbycondensate pumpstartedautoma'tically (toincreasemainfeedwater pumpsuctionpressure).
MainFeedwater pumpsuctionpressurewasdecreasing duetotheincreased feedwater flowtotheS/Gs.The"A"and"B"S/Glevelscontinued toincreaseandbeforetheControlRoomoperatorcouldshift'theFRVstomanual,ADFCSautomatically shiftedtheFRVstomanual.WhiletheControlRoomoperatorwasmanuallyloweringthesetpoints fortheFRVcontrollers, tocontrolS/Glevel,thefollowing alarmsannunciated andfeedwater isolation o'ccurred onbothS/Gs;G-4(S/GAHILEVELCHANNELALERT67%)andG-6(S/GBHILEVELCHANNEL,ALERT67%).Immediately following thefeedwater isolation, thecondensate boosterpumpstrippedonhigh*pressure.
Aloadde'crease wasinitiated at10%/hourtolessentheimpactofunstableS/Glevels.Mainfeedwater totheS/Gswascontrolled inmanualinordertostopsecondary systemoscillations thatwereoccurring duetotheevent.DuringtheS/Glevelstabile.zation, S/Gfeedwater isolation occurredseveraltimes.TheS/Glevelsweresubsequently stabilized andmainfeedwater controlwasreturnedtoautomatic.
Aftermainfeedwater controlwasreturnedtoautomatic theloaddecreasewasterminated.
Totalloaddecreasewasapproximately 0.54fullpowerduringtheevent.Subsequently, thecondensate lowpressureheaterbypassvalvewasclosed,thecondensate boosterpumpswererestored, andthestandbycondensate pumpwassecuredandrealigned forautomatic standby.~~VACSOAVSSAAi$4$l  


II1CI<e<ws~l043ILICENSEEEVENTREPORTILER1TEXTCONTINUATIONVS.1VCLSA11SOVLATO1YCOMMISSIONATT1DVCOOVS<<OSISO&10lS>et<1%$~ISISS1ACILITTIIAMtIIIDOC%STIIVMOS1lllLSIIIIVMOI1ISISSOVT<<T<ALrr~AOIISIR.E.GinnaNuclearPowerPlantTuTnr<<r<rr<Aeer<rr<rrr,~~A<rcI<<r<<<~LvIITIo5ooo24491-0Q9-0005o>09CINOPERABLESTRUCTURES,COMPONENTS',ORSYSTEMSTHATCONTRIBUTEDTOTHEEVENT:None.'.OTHERSYSTEMSORSECONDARYFUNCTIONSAFFECTED:E.None.METHODOFDISCOVERY:TheeventwasimmediatelyapparentduetoalarmsandindicationsintheControlRoom.OPERATOR.ACTION:TheControlRoomoperatorstookimmediatemanualactionstocontrolS/Glevels,reducepowerlevel,andstabilizetheplant.Subsequently,theControlRoomoperatorsnotifiedhighersupervisionandtheNuclearRegulatoryCommissionper10CFR50.72,non-emergency,4hournotification.G.SAFETYSYSTEMRESPONSES:The"A"and"B"FRVsclosedautomaticallyfromthefeedwaterisolationsignal.III.CAUSEOF>wrylyA.IMMEDIATECAUSE:Thefeedwaterisolationofthe"A"and"B"S/Gwasduetothe"A"and"B"S/Gnarrowrangelevelsbeing)/=67%.~<AC101M)00A<040<  
II1CI<e<ws~l043ILICENSEEEVENTREPORTILER1TEXTCONTINUATION VS.1VCLSA11SOVLATO1Y COMMISSION ATT1DVCOOVS<<OSISO&10lS>et<1%$~ISISS1ACILITTIIAMtIIIDOC%STIIVMOS1lllLSIIIIVMOI1ISISSOVT<<T<AL rr~AOIISIR.E.GinnaNuclearPowerPlantTuTnr<<r<rr<Aeer<rr<rrr,~~A<rcI<<r<<<~LvIITIo5ooo24491-0Q9-0005o>09CINOPERABLE STRUCTURES, COMPONENTS',
ORSYSTEMSTHATCONTRIBUTED TOTHEEVENT:None.'.OTHERSYSTEMSORSECONDARY FUNCTIONS AFFECTED:
E.None.METHODOFDISCOVERY:
Theeventwasimmediately apparentduetoalarmsandindications intheControlRoom.OPERATOR.
ACTION:TheControlRoomoperators tookimmediate manualactionstocontrolS/Glevels,reducepowerlevel,andstabilize theplant.Subsequently, theControlRoomoperators notifiedhighersupervision andtheNuclearRegulatory Commission per10CFR50.72,non-emergency, 4hournotification.
G.SAFETYSYSTEMRESPONSES:
The"A"and"B"FRVsclosedautomatically fromthefeedwater isolation signal.III.CAUSEOF>wrylyA.IMMEDIATE CAUSE:Thefeedwater isolation ofthe"A"and"B"S/Gwasduetothe"A"and"B"S/Gnarrowrangelevelsbeing)/=67%.~<AC101M)00A<040<  


IIACPereMl044lLICENSEEEVENTREPORT(LER)TEXTCONTINUATIONV.5.IIVCLTAW150VLATOATCISPAII55IISIAPPAOv50Ov5rrOIITC~IOAPTlrprA555ITI,55PACILITTrIAAI5IIIOOCIIKTIIVAIOCAIllL5AIILAPCIAI5!TTarrarrTrALeegVIeIOrrePAO5I5IR.E.GinnaNuclearPowerPlantTSCTnprrrere~rreereep.~oeeoawrTACrrerrrr~VVIITIosooo2441-009-0006av09INTERMEDIATECAUSES:The"A"and"B".S/Gnarrowrangelevelswere>/=67%duetoincreasedfeedwaterflowtobothS/GscausedbyaperturbationoftheADFCS.Theperturbationofth'eADFCSwasapparentlyduetoelectromagneticnoisespikesaffectingthefeedwaterheaderpressureinputstoADFCS,(i.e.P501andP502).C.ROOTCAUSE:-Afterextensivetroubleshooting,itwasdeterminedthatthespikesthataffectedtheADFCSfeedwaterheaderpressureinputswerecausedbythede-energiza-tionofRelayARSO,locatedinthefirerelaypanel.Thisrelay,whichlightsthedieselfirepumptroublelight,de-energizesapproximately10to15secondsafteradieselfirepumpstart.Duringthisde-energization,inductive"kickback"causesanelectro-magneticnoisespiketobegeneratedandinducedintothefeedwaterheaderpressureinputs.Thesignalcablescarryingthefeedwaterheaderpressuretransmitter(PT-.501andPT-502)inputssharesomecommoncabletrayswiththe'DCpowersourcefortheARSOrelay,andanoisespikewasinducedfromtheARSOrelaycabletothefeedwaterheaderpressureinputcables.ANALYSISOF&TENTThisevent.isreportableinaccordancewith10CFR50.73,LicenseeEventReportSystem,item(a)(2)(iv),whichrequiresreportingof,"anyeventorconditionthatresultedinmanualcrautomaticactuationofanyEngineeredSafetyFeature(ESF)includingtheReactorProtectionSystem(RPS)".Thefeedwaterisolationofthe"A"and"B"S/GswasanautomaticactuationofanESFsystem.~rAC~O1rerTATI  
IIACPereMl044lLICENSEEEVENTREPORT(LER)TEXTCONTINUATION V.5.IIVCLTAW150VLATOAT CISPAII55IISI APPAOv50Ov5rrOIITC~IOAPTlrprA555ITI,55PACILITTrIAAI5IIIOOCIIKTIIVAIOCAIllL5AIILAPCIAI5!TTarrarrTrAL eegVIeIOrrePAO5I5IR.E.GinnaNuclearPowerPlantTSCTnprrrere~rreereep.~oeeoawrTACrrerrrr~VVIITIosooo2441-009-0006av09INTERMEDIATE CAUSES:The"A"and"B".S/Gnarrowrangelevelswere>/=67%duetoincreased feedwater flowtobothS/Gscausedbyaperturbation oftheADFCS.Theperturbation ofth'eADFCSwasapparently duetoelectromagnetic noisespikesaffecting thefeedwater headerpressureinputstoADFCS,(i.e.P501andP502).C.ROOTCAUSE:-Afterextensive troubleshooting, itwasdetermined thatthespikesthataffectedtheADFCSfeedwater headerpressureinputswerecausedbythede-energiza-tionofRelayARSO,locatedinthefirerelaypanel.Thisrelay,whichlightsthedieselfirepumptroublelight,de-energizes approximately 10to15secondsafteradieselfirepumpstart.Duringthisde-energization, inductive "kickback" causesanelectro-magneticnoisespiketobegenerated andinducedintothefeedwater headerpressureinputs.Thesignalcablescarryingthefeedwater headerpressuretransmitter (PT-.501andPT-502)inputssharesomecommoncabletrayswiththe'DCpowersourcefortheARSOrelay,andanoisespikewasinducedfromtheARSOrelaycabletothefeedwater headerpressureinputcables.ANALYSISOF&TENTThisevent.isreportable inaccordance with10CFR50.73,LicenseeEventReportSystem,item(a)(2)(iv),
'I MACPereM19441LICENSEEEVENTREPORT(LERITEXTCONTINUATIONV.l.IIVCLCAA1lQULATOAYCOMMI5OQMPAPPAOYlOOMlrrQ)IlQ~IQAl>ceIAlSlrll1$I'ACILITYNAlllIIIQOCKlTHU%%$1lllLIIIMVeell1Illj~OvlrrerALrrlvleIorrA~AOllllR.E.GinnaNuclearPowerPlantTlxTIA'~r~.~ereereMIeIACPerrrr~'llIITIosooo24491-0-9-007os09Anassessmentwasperformedconsideringboththesafetyconsequencesandimplicationsofthiseventwiththefollowingresultsandconclusions:Therewerenooperationalorsafetyconsequencesorimplicationsattributedtothefeedwaterisolationsbecause:oThefeedwaterisolationsoccurredattherequiredS/Glevels.oTheplantwasquicklystabilizedandmanualcontroloftheFRVswasaccomplishedtomitigatethetransient.oAsthefeedwater'solationoccurredasdesigned,theassumptionsoftheFSARforsteamlinebreakweremet.Basedontheabove,-itcanbeconcludedthatthepublic'shealthandsafetywereassuredatalltimes.V.CORRECTIVEACTIONA.ACTIONTAKENTORETURNAFFECTEDSYSTEMSTOPRE-EVIBFZNORMALSTATUS:0TheDieselFirePumpwastemporarilyremovedfromservicependingtheoutcomeofrootcausetroubleshootinganddetermination.(ThepumpwasreturnedtoserviceafteranoisesuppressiondiodewasinstalledacrossrelayAR80).0WhenS/Glevelswerestabilized,subsequenttotheADFCSperturbationtermination,theFRVswereplacedinautomaticcontrol.0AftertheplanthadbeenstabilizedandtheFRVsreturnedtoautomaticcontrol,thecondensatelowpressureheaterbypassvalvewasclosed,thecondensateboosterpumpswererestoredandthestandbycondensatepumpwassecuredandrealignedforautomaticstandby.rrACPOAMel4ll  
whichrequiresreporting of,"anyeventorcondition thatresultedinmanualcrautomatic actuation ofanyEngineered SafetyFeature(ESF)including theReactorProtection System(RPS)".Thefeedwater isolation ofthe"A"and"B"S/Gswasanautomatic actuation ofanESFsystem.~rAC~O1rerTATI  
'I MACPereM19441LICENSEEEVENTREPORT(LERITEXTCONTINUATION V.l.IIVCLCAA1lQULATOAY COMMI5OQM PAPPAOYlOOMlrrQ)IlQ~IQAl>ceIAlSlrll1$I'ACILITY NAlllIIIQOCKlTHU%%$1lllLIIIMVeell1Illj~OvlrrerALrrlvleIorrA~AOllllR.E.GinnaNuclearPowerPlantTlxTIA'~r~.~ereereMIeIACPerrrr~'llIITIosooo24491-0-9-007os09Anassessment wasperformed considering boththesafetyconsequences andimplications ofthiseventwiththefollowing resultsandconclusions:
Therewerenooperational orsafetyconsequences orimplications attributed tothefeedwater isolations because:oThefeedwater isolations occurredattherequiredS/Glevels.oTheplantwasquicklystabilized andmanualcontroloftheFRVswasaccomplished tomitigatethetransient.
oAsthefeedwater
'solation occurredasdesigned, theassumptions oftheFSARforsteamlinebreakweremet.Basedontheabove,-itcanbeconcluded thatthepublic'shealthandsafetywereassuredatalltimes.V.CORRECTIVE ACTIONA.ACTIONTAKENTORETURNAFFECTEDSYSTEMSTOPRE-EVIBFZ NORMALSTATUS:0TheDieselFirePumpwastemporarily removedfromservicependingtheoutcomeofrootcausetroubleshooting anddetermination.
(Thepumpwasreturnedtoserviceafteranoisesuppression diodewasinstalled acrossrelayAR80).0WhenS/Glevelswerestabilized, subsequent totheADFCSperturbation termination, theFRVswereplacedinautomatic control.0Aftertheplanthadbeenstabilized andtheFRVsreturnedtoautomatic control,thecondensate lowpressureheaterbypassvalvewasclosed,thecondensate boosterpumpswererestoredandthestandbycondensate pumpwassecuredandrealigned forautomatic standby.rrACPOAMel4ll  


NAC1vv~(~ILICENSEEEVENTREPORTILER)TEXTCONTINUATION-U,S,NUCLTAAAIOULATOAVCOMAIITSIONA>>AOVlOOUINO)1$0&I04TIct<ACS~IlI'l$FACILITYNAIACIIIOOCAtTNU~tAIllLtANLAA4IAIIIT~OVINTIALv1AAVISlONA~AOIIlIR.E.GinnaNuclearPowerPlantTerrIA~>>A>>A~.~>>>>VV>>VNACAV>>~SUIITIo5oo'o24491-009-0008DFO9B.ACTIONTAKENORPLANNEDTOPREVENTRECURE&NCE:o*Areverse-biaseddiodewastemporarilyinstalledacrossthecoilofAR80onNovember15,1991andsubsequenttestingdeterminedthatthespikesfromtheAR80circuit,affectingADFCSfeedwaterpressureinputsfollowingdieselfirepump,starts,wereeliminated.Thisnoisesuppressiondiode'waspermanentlyinstalledonNovember18,1991.AfterreviewingtheresultsoftroubleshootingandthediscussionwithWestinghouse,thefollowingisanoutlineofthecorrectiveactionsbeingtakenorplannedinresponsetotheADFCSnoisespikingevents:oShortTermResponsea)OperationspersonnelweremadeawarethatonesourceofspikesonADFCSwaseliminated,butthatspikesfromothersources,whilereducedinfrequency.andmagnitude,mightoccur.OperationswillidentifyanynewspikesontheADFCSbysubmittingaWorkRequest/TroubleReport(WR/TR).b)AWR/TRwassubmittedforinstallationofadiodeforthefireboosterpumprelayAR85(whichalsoproducessmallspikesonADFCS).However,thesespikesarenotofthesamemagnitudeasthenoisespikesthatwerecausedbytheDieselFirePumpstarts.oIntermediateTermResponseElectricalEngineeringwillconsultwithWestinghouseconcerningadatabasechangetoincreasetheADFCSslewratefilterconstant.Thisfilterisusedtodampenanyabruptchangestofeedwaterregulatingvalvedemandintheeventthatfeedwaterheaderpressureinputvaluesarerejectedduetonoisespikes.ItisthoughtNACIOAVTAAA~T4ll  
NAC1vv~(~ILICENSEEEVENTREPORTILER)TEXTCONTINUATION-U,S,NUCLTAAAIOULATOAV COMAIITSION A>>AOVlOOUINO)1$0&I04TIct<ACS~IlI'l$FACILITYNAIACIIIOOCAtTNU~tAIllLtANLAA4IAIIIT~OVINTIALv1AAVISlONA~AOIIlIR.E.GinnaNuclearPowerPlantTerrIA~>>A>>A~.~>>>>VV>>VNACAV>>~SUIITIo5oo'o24491-009-0008DFO9B.ACTIONTAKENORPLANNEDTOPREVENTRECURE&NCE:
o*Areverse-biased diodewastemporarily installed acrossthecoilofAR80onNovember15,1991andsubsequent testingdetermined thatthespikesfromtheAR80circuit,affecting ADFCSfeedwater pressureinputsfollowing dieselfirepump,starts,wereeliminated.
Thisnoisesuppression diode'waspermanently installed onNovember18,1991.Afterreviewing theresultsoftroubleshooting andthediscussion withWestinghouse, thefollowing isanoutlineofthecorrective actionsbeingtakenorplannedinresponsetotheADFCSnoisespikingevents:oShortTermResponsea)Operations personnel weremadeawarethatonesourceofspikesonADFCSwaseliminated, butthatspikesfromothersources,whilereducedinfrequency.
andmagnitude, mightoccur.Operations willidentifyanynewspikesontheADFCSbysubmitting aWorkRequest/Trouble Report(WR/TR).b)AWR/TRwassubmitted forinstallation ofadiodeforthefireboosterpumprelayAR85(whichalsoproducessmallspikesonADFCS).However,thesespikesarenotofthesamemagnitude asthenoisespikesthatwerecausedbytheDieselFirePumpstarts.oIntermediate TermResponseElectrical Engineering willconsultwithWestinghouse concerning adatabasechangetoincreasetheADFCSslewratefilterconstant.
Thisfilterisusedtodampenanyabruptchangestofeedwater regulating valvedemandintheeventthatfeedwater headerpressureinputvaluesarerejectedduetonoisespikes.ItisthoughtNACIOAVTAAA~T4ll  


NIICformSOSA(04SISACILITYNASIEIllLICENSEEEVENTREPORTILERITEXTCONTINUATIONCOCKETNUIAOEII(ElU.E,NUCLEA(lAECULATOAYCOSSSIIS3(ONASSAOYEOOUINOTISOW(04fExs(RES'S(SI'ESLE(iNUIAOEAI~I$SCUSNTrALosvrsrorrNONvmO~ACE(j(R.E.GinnaNuclearPowerPlantTExT(rfmoroA(sosrsrosrrsos,omsNsooonor(Y(lcform~'ll(illosooo24491-009-0009OF09thatthisfiltercanalso"LockIn"anerroneousvaluefollowingafeedwaterheadeipressurespike.Increasingthisconstantwillmorequicklyrestoreacorrectvalueforfeedwaterheaderpressure,afteraspikehasdecayed.Thespikeslastlessthanfive(5)seconds.oLongTermResponsea)b)ElectricalEngineeringwillcheckwithWestinghousefortheresultsoftheirreviewofADFCSarbitrationerrorcheckingsoftware.ThisreviewwilldetermineiftheerrorcheckingroutinefortheswitchingtoarbitrationvaluesinsteadoffeedwaterheaderpressurefieldinputvaluesissubstitutingerroneousvaluesforfeedwaterheaderpressureusedinFRVdemandcalculations.ElectricalEngineeringwillevaluatetheroutingoffeedwaterheaderpressureinputcircuits(tothe-ADFCS),andwillidentifyanyadditionalmodificationsthatmayberequiredtoeliminatetheelectromagneticnoisespikeconcern.VX.ADDITXONALNFORMATIONA.FAILEDCOMPONENTS:NoneB.PREVIOUSLERsONSIMILAREVENTS:AsimilarLEReventhistoricalsearchwasconductedwiththefollowingresults:.NodocumentationofimilarLEReventswiththesamerootcausecouldbe.identified.C.SPECIALCO~BFZS:None.NACs01loSSOArS4TI}}
NIICformSOSA(04SISACILITYNASIEIllLICENSEEEVENTREPORTILERITEXTCONTINUATION COCKETNUIAOEII(ElU.E,NUCLEA(lAECULATOAY COSSSIIS3(ON ASSAOYEOOUINOTISOW(04fExs(RES'S(SI'ESLE(iNUIAOEAI~I$SCUSNTrAL osvrsrorr NONvmO~ACE(j(R.E.GinnaNuclearPowerPlantTExT(rfmoroA(sosrsrosrrsos, omsNsooonor (Y(lcform~'ll(illosooo24491-009-0009OF09thatthisfiltercanalso"LockIn"anerroneous valuefollowing afeedwater headeipressurespike.Increasing thisconstantwillmorequicklyrestoreacorrectvalueforfeedwater headerpressure, afteraspikehasdecayed.Thespikeslastlessthanfive(5)seconds.oLongTermResponsea)b)Electrical Engineering willcheckwithWestinghouse fortheresultsoftheirreviewofADFCSarbitration errorcheckingsoftware.
Thisreviewwilldetermine iftheerrorcheckingroutinefortheswitching toarbitration valuesinsteadoffeedwater headerpressurefieldinputvaluesissubstituting erroneous valuesforfeedwater headerpressureusedinFRVdemandcalculations.
Electrical Engineering willevaluatetheroutingoffeedwater headerpressureinputcircuits(tothe-ADFCS),andwillidentifyanyadditional modifications thatmayberequiredtoeliminate theelectromagnetic noisespikeconcern.VX.ADDITXONAL NFORMATION A.FAILEDCOMPONENTS:
NoneB.PREVIOUSLERsONSIMILAREVENTS:AsimilarLEReventhistorical searchwasconducted withthefollowing results:.Nodocumentation ofimilarLEReventswiththesamerootcausecouldbe.identified.
C.SPECIALCO~BFZS:None.NACs01loSSOArS4TI}}

Revision as of 12:10, 29 June 2018

LER 91-009-00:on 911111,steam Generator Feedwater Isolations Occurred on Both Steam Generators.Caused by Perturbations of Advanced Digital Feedwater Control Sys.Feedwater Regulating Valves Manually controlled.W/911211 Ltr
ML17262A680
Person / Time
Site: Ginna Constellation icon.png
Issue date: 12/11/1991
From: BACKUS W H, MECREDY R C
ROCHESTER GAS & ELECTRIC CORP.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-91-009, LER-91-9, NUDOCS 9112170532
Download: ML17262A680 (22)
v • d • e


Text

e!'CCELERATED DISTRIBUTION DEMONRATION SYSTEM'EGULATORY INFORMATION DISTRIBUTION SYSTEM(RIDS)ACCESSION NBR:9112170532 DOC.DATE:

91/12/11NOTARIZED:

NODOCKETFACIL:50-244 RobertEmmetGinnaNuclearPlant,Unit1,Rochester G05000244AUTH.NAME'AUTHORAFFILIATION BACKUS,W.H.

Rochester Gas&ElectricCorp.MECREDY,R.C.

Rochester Gas&ElectricCorp..RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER91-009-00:on 911111,steam generator feedwater isolations'ccurred onbothsteamgenerators.

Causedbyperturbations of~advanceddigitalfeedwater controlsys.Feedwater regulating valvesmanuallycontrolled.W/911211 ltr.DISTRIBUTION CODE:IE22TCOPIESRECEIVED:LTR gENCLgSIZE:i(7TITLE:50.73/50.9 LicenseeEventReport(LER),IncidentRpt,etc.DNOTES:License Expdateinaccordance with10CFR2,2.109(9/19/72).

05000244ARECIPIENT IDCODE/NAME PD1-3LAJOHNSON,A INTERNAL:

ACNWAEOD/DSP/TPAB.NRR/DET/ECMB 9HNRR/DLPQ/LHFB10 NRR/DOEA/OEAB NRR/DST/SELB 8DNRR~ST/SPLB8DlN1LE01EXTERNAL:

EG&GBRYCE,J.H NRCPDRNSICPOORE,W.COPIESLTTRENCL111122111111111111111'1331111RECIPIENT IDCODE/NAME PD1-3PDAEOD/DOAAEOD/ROAB/DS PNRR/DET/EMEB 7ENRR/DLPQ/LPEB10 NRR/DREP/PRPB11 NRR/DST/SICB8H3 NRR/DST/SRXB 8ERES/DSIR/EIB LSTLOBBYWARDNSICMURPHY,G.A NUDOCSFULLTXTCOPIESLTTRENCL1111221.11122111111111111DDDNOTETOALL"RIDS'ECIPIENTS:

DDPLEASEHELPUSTOREDUCEi'i'ASTE!

CONTACTTHEDOCUlii!EiiT CONTROLDESK,ROOliIPl-37(EXT.2M79)TQLILIih!INAl'EYOURNAiIF.FROii1DISTRIBUTION LISTSFORDOCUiiIENTS YOUDON'TNEED!FULLTEXTCONVERSION REQUIREDTOTALNUMBEROFCOPIESREQUIRED'TTR 31ENCL31 ake0 ROCHESTER GASANDELECTRICCORPORATION ns~~~'w~~st,ss@ssee9EASTAVENUE,ROCHESTER N.K14649-0001

",ROBERTCMECREDYVicePsesidens Cfnnns'ueiessPsodueBun TELEPiSONE AREACUE7s65462700December11,1991U.S.NuclearRegulatory Commission DocumentControlDeskWashington, DC20555

Subject:

LER91-009,Automatic Feedwater ControlPerturbations, DueTo'lectromagnetic NoiseSpikesFromUnrelated RelayActuation, CausedSteamGenerator Feedwater Isolation onHighLevelR.E.GinnaNuclearPowerPlantDocketNo.50-244Inaccordance with10CFR50.73,LicenseeEventReportSystem,item.(a)(2)(iv),

whichrequiresareportof,"anyeventorcondition thatresultedinmanualorautomatic actuation ofanyEngineered SafetyFeature(ESF),including theReactorProtection System(RPS)",theattachedEventReportLER91-009isherebysubmitted.

Thiseventhasinnowayaffectedthepublic'shealthandsafety.Verytrulyyours,RobertC.MecredyxcoU.S.NuclearRegulatory Commission RegionI475Allendale RoadKingofPrussia,PA19406GinnaUSNRCSeniorResidentInspector 0I NACtera000ISASIUCENSEEEVENTREPORT(LER)U*NUOLCAR RICULATQR'v coeal~At<<IIOVID OMSNO,SIMOIOrrlxSIRISI/Sr/ttfACILITYNA<<rtIllR.E.GinnaNuclearPowerPlantDOCXITNVMIIRQlo6ooo244>as09'"Automatic Feedwater ControlPerturbations, DueToElectromagnetic Noise.SpikesFromUnrelated RelaActuation musedSteamGenerator Feedwater Isolation onHihLvelIVINTOATIISILIRNVMICRIMAltORTOATSITIOTHI1fACILI'Till INVOLVIOQlMONTrrOAYYCARYCAJI~IOVIrlrl*L

")AIVRIQrrNVMIIArlerrreIAMONTHOAYYCARfACrLIT'rHAMILOOCXITNVMIIRISI 0600091910090012119106000OtC1ATINCMOOCIIILIYIL098~i>rio,.W)Wi$~g'.+THII1lfORTIISVSMITTCO tURSVANTTS0.<<0SIII 00.<<004IIIIIIIS0.0004IIIIIII SS.IM4IIIIIMISIACI4IIIIIHISO.IMle)llllrlSS.IMirl, MMlrlllIMMNIQIM.TSUIQII4 M.TIleIQIIIIM.TSNIQIIX4 M.TSVIQIlleIM.TS4IQIIrlM.T04IQllrllM.TSNIQIIHXIIAI M.TSNIQ)lralltl M.TSIIIQllel 0THI1IOVI1SirINTSOf10Cf1f<ICrrreieeeererereerarle<<eeeeNIIITLTllel0THc1/S<<ee<<V4AAreerr~erierrre4Tr<<LNRCfareLICINSIICONTACTtO1THISLIRlltlNAMtTILltHONI NVMSIRWesleyH.BackusARIACOOtTechnical Assistant totherationsManaer315524-4446COM<<LITCONILINCf01IACHCOM<<ONINT fAILURCOtICRIIIO INTHISRltORTllllCAVStSYSTSMCOMtOHINTMANVfAOTURIRAPrr"""~">""+CAVSISYSTSMCOMtONCNT TONtROI.5":ij>S.<~,~86:

'jjpQ%.(@~kgMANVfAOTURINltORTASLTONtROSe~rg~@4~@

IVtfLtMINTALRtt01TIXtlCTIOIIIIYCtlllfer,reer<<rraIX<</CTIOSVSMISSIONOATIINOLIITAAOTII<<erraIrofireea,I~..rterer<<errNf INaeer<<vrre<<rrr trteerarre

<<ewll~ICXflCTIOLvll<<ISCIONOATII'IIIMOHTHCAYYIAROnNovember11,1991atapproximately 1214EST,withthereactoratapproximately 98%fullpower,steamgenerator feedwater isolations occurredonbothsteamgenerators.

Thesefeedwater isolations werecausedbyperturbations oftheadvanceddigitalfeedwater controlsystemwhichincreased feedwater flowtot1'teamgenerators.

Immediate operatoractionwastomanuallycontrolthefeedwater regulating valvestoreducesteamgenerator levelsandstabilize theplant.Theunderlying causeoftheeventwasdetermined tobeelectro-magneticnoisespikesaffecting theadvanceddigitalfeedwater controlsystem.Corrective actiontakenwastomodifyspecificrelaycircuitsthatwerecausingthesespikes.NACfaaSMIIASI Il IIACSeeMI000ILICENSEEEVENTREPORT(LER)TEXTCONTINUATION V.I.IIVCLCAAAlOVLATOAV

<<OMMHNISI

/AtPAOVKOOMAMll%0&I04a>>tiACSll)IWSI'ACILITYIIAMCIIIOOCKETIIVM~EAl11LlllIIVMOIIIIII'NOVINT<Al,

'ttV4%8UA~AOIIIIR.E.GinnaNuclearPowerPlantTQTTIII~~%MA~.~y480OAVNACAnil~'ilIITI24491-009-0002or0PRE-EVENT PLANTCONDITIONS Theplantwasatapproximately 98%steadystatereactorpowerwithnomajoractivities inprogress.

TheMaintenance Department wasperforming troubleshooting, todetermine thesourceofelectromagnetic noise,spikesintheAdvancedDigitalFeedwater ControlSystem(ADFCS).Thetroubleshoot-ingwasbeingperformed undertheguidanceofWorkOrderpackagef9122181.

Unexplained electromagnetic

'noisespikeproblemswereidentified previously ascoinciding withthestartofthedieselfirepump,andwhichhadminoreffectontheADFCScontrolfunctions.

TheADFCSwasinstalled duringthe1991"AnnualRefueling andMaintenance Outage.Theseelectromagnetic noisespikeswerefirstnoticedonJune4,1991,whenaminorfeedwater perturbation

occurred, following adieselfirepumpstart.SinceJune4,spikeshaveoccurredalmosteverytimethediesel'firepumphasstarted.TheADFCS.hashandledspikeswithnonoticeable feedwater perturbations, exceptfortwo(2)occasions.

Theseoccasions, thefirstonJune4,1991andthesecondonSeptember 13,1991,werehandledbytheADFCSinautomatic andnooperatoractionwasrequired.

Therehasbeenanongoingsearchforthepossiblesourceofthiselectromagnetic noisespikesothatitcouldbecorrected.

Aspartofthisongoingsearch,theElectrical Engineering Department evaluated theircabletraydatabaseandidentified circuitE174asapossiblesource.CircuitE174isthe125VoltDCpowerfeedtothefirerelaypanelandsharessomecabletrayswithADFCSinputcables,mostnotably,thefeedwater headerpressureinputstoADFCS'P501 andP502).'IACAOAMAAAital

NIICPe<<<<1~044II.'ICENSEE EVENTREPORTILER)TEXTCONTINUATION

<<U.S.NUCLIAAAIOULAT01T COMMITeION

/AAAAOV%0OMINOTISOWIOAT)eAt1%$~III1$I'ACILITY NAMIIIIR.E.GinnaNuclearPowerPlantTQ(TIA'<<<<44NMCO4~.<<<<MMM41<<<<MNOMIC/Oral~TIIITIDOC%ITNUNMtNITIosooo244LlllNUMOl1IIIvTAA,'AQVANT<<AL 1(V4<<O<<<<41<<<<4191-00900~AOIIS030'9Westinghouse ElectricCorporation (themanufacturer oftheADFCS)wascontacted andcouldnotexplaintheADFCSexcursions basedon,dataavailable.

Inconjunction withtheElectrical Engineering Department, Westinghouse hadpreviously recommended thattheshielding andgrounding schemesforallADFCSinputsbechecked.TheseinputswerecheckedinAugust,1991.Thischeckindicated thatallADFCSinputsarecorrectly shieldedandgrounded.

DESCRIPTION OFEVENTA.DATESANDAPPROXIMATE TIMESOFMAZOROCCURRENCES:

00November11,1991,1214EST:EventDateandApproximate Time.November11,1991,1214EST:Discovery DateandApproximate Time.oNovember15,1991:CauseofEMPnoisespikeidentified andsuppressed toacceptable levels.WGBFZ:OnNovember11,1991,atapproximately 1214EST,withthereactoratapproximately 98%fullpower,thedieselfirepumpwasstarted,asrequiredforADFCStroubleshooting perWork.Orderf9122181.

Approximately thirty(30)secondsafterthedieselfirepumpwasstartedan"ADFCSSystemTrouble"alarm(G-22)wasreceived.

TheControlRoomoperatorresponsible forfeedwater controlhadpre-positioned himselfinfrontofthe"A"and"B"S/GMainFeedwater Regulating Valves(FRV)controlpanelpriortothestartofthedieselfirepump.~<<1CADAMTQAA<<tel

1IICSeam~I$4$lLICENSEEEVENTREPORTILER)TEXTCONTINUATION V.S.IIVCLCA1AIOVLATOAY COSSSSt%IOII rASSAOYCOOU~IIOSI$0&IOSTIIAI1$$~ITI%$AACILITYNASISI1I-OOCKSTIIVIAOIAIllL$1NLAN$1I~ISSOUS>S<AL ASYCK)UU1'UA~A4$ISIR.E.GinnaNuclearPowerPlantTQ(T/ITmewAIASS1~.~e4004HVJYACAMID~YlIIllosooo24491-009-0004or09Atthistime,theControlRoomoperatornoticedthatboththe"A"and"B"SteamGenerator (S/G)mainfeedwater flowswerepeggedhigh.withboth"A"and"B"S/GMainFeedwater Regulating Valvescontinuing toopenfurther.Thecondensate lowpressureheater.bypassvalveopenedautomatically andthestandbycondensate pumpstartedautoma'tically (toincreasemainfeedwater pumpsuctionpressure).

MainFeedwater pumpsuctionpressurewasdecreasing duetotheincreased feedwater flowtotheS/Gs.The"A"and"B"S/Glevelscontinued toincreaseandbeforetheControlRoomoperatorcouldshift'theFRVstomanual,ADFCSautomatically shiftedtheFRVstomanual.WhiletheControlRoomoperatorwasmanuallyloweringthesetpoints fortheFRVcontrollers, tocontrolS/Glevel,thefollowing alarmsannunciated andfeedwater isolation o'ccurred onbothS/Gs;G-4(S/GAHILEVELCHANNELALERT67%)andG-6(S/GBHILEVELCHANNEL,ALERT67%).Immediately following thefeedwater isolation, thecondensate boosterpumpstrippedonhigh*pressure.

Aloadde'crease wasinitiated at10%/hourtolessentheimpactofunstableS/Glevels.Mainfeedwater totheS/Gswascontrolled inmanualinordertostopsecondary systemoscillations thatwereoccurring duetotheevent.DuringtheS/Glevelstabile.zation, S/Gfeedwater isolation occurredseveraltimes.TheS/Glevelsweresubsequently stabilized andmainfeedwater controlwasreturnedtoautomatic.

Aftermainfeedwater controlwasreturnedtoautomatic theloaddecreasewasterminated.

Totalloaddecreasewasapproximately 0.54fullpowerduringtheevent.Subsequently, thecondensate lowpressureheaterbypassvalvewasclosed,thecondensate boosterpumpswererestored, andthestandbycondensate pumpwassecuredandrealigned forautomatic standby.~~VACSOAVSSAAi$4$l

II1CI<e<ws~l043ILICENSEEEVENTREPORTILER1TEXTCONTINUATION VS.1VCLSA11SOVLATO1Y COMMISSION ATT1DVCOOVS<<OSISO&10lS>et<1%$~ISISS1ACILITTIIAMtIIIDOC%STIIVMOS1lllLSIIIIVMOI1ISISSOVT<<T<AL rr~AOIISIR.E.GinnaNuclearPowerPlantTuTnr<<r<rr<Aeer<rr<rrr,~~A<rcI<<r<<<~LvIITIo5ooo24491-0Q9-0005o>09CINOPERABLE STRUCTURES, COMPONENTS',

ORSYSTEMSTHATCONTRIBUTED TOTHEEVENT:None.'.OTHERSYSTEMSORSECONDARY FUNCTIONS AFFECTED:

E.None.METHODOFDISCOVERY:

Theeventwasimmediately apparentduetoalarmsandindications intheControlRoom.OPERATOR.

ACTION:TheControlRoomoperators tookimmediate manualactionstocontrolS/Glevels,reducepowerlevel,andstabilize theplant.Subsequently, theControlRoomoperators notifiedhighersupervision andtheNuclearRegulatory Commission per10CFR50.72,non-emergency, 4hournotification.

G.SAFETYSYSTEMRESPONSES:

The"A"and"B"FRVsclosedautomatically fromthefeedwater isolation signal.III.CAUSEOF>wrylyA.IMMEDIATE CAUSE:Thefeedwater isolation ofthe"A"and"B"S/Gwasduetothe"A"and"B"S/Gnarrowrangelevelsbeing)/=67%.~<AC101M)00A<040<

IIACPereMl044lLICENSEEEVENTREPORT(LER)TEXTCONTINUATION V.5.IIVCLTAW150VLATOAT CISPAII55IISI APPAOv50Ov5rrOIITC~IOAPTlrprA555ITI,55PACILITTrIAAI5IIIOOCIIKTIIVAIOCAIllL5AIILAPCIAI5!TTarrarrTrAL eegVIeIOrrePAO5I5IR.E.GinnaNuclearPowerPlantTSCTnprrrere~rreereep.~oeeoawrTACrrerrrr~VVIITIosooo2441-009-0006av09INTERMEDIATE CAUSES:The"A"and"B".S/Gnarrowrangelevelswere>/=67%duetoincreased feedwater flowtobothS/Gscausedbyaperturbation oftheADFCS.Theperturbation ofth'eADFCSwasapparently duetoelectromagnetic noisespikesaffecting thefeedwater headerpressureinputstoADFCS,(i.e.P501andP502).C.ROOTCAUSE:-Afterextensive troubleshooting, itwasdetermined thatthespikesthataffectedtheADFCSfeedwater headerpressureinputswerecausedbythede-energiza-tionofRelayARSO,locatedinthefirerelaypanel.Thisrelay,whichlightsthedieselfirepumptroublelight,de-energizes approximately 10to15secondsafteradieselfirepumpstart.Duringthisde-energization, inductive "kickback" causesanelectro-magneticnoisespiketobegenerated andinducedintothefeedwater headerpressureinputs.Thesignalcablescarryingthefeedwater headerpressuretransmitter (PT-.501andPT-502)inputssharesomecommoncabletrayswiththe'DCpowersourcefortheARSOrelay,andanoisespikewasinducedfromtheARSOrelaycabletothefeedwater headerpressureinputcables.ANALYSISOF&TENTThisevent.isreportable inaccordance with10CFR50.73,LicenseeEventReportSystem,item(a)(2)(iv),

whichrequiresreporting of,"anyeventorcondition thatresultedinmanualcrautomatic actuation ofanyEngineered SafetyFeature(ESF)including theReactorProtection System(RPS)".Thefeedwater isolation ofthe"A"and"B"S/Gswasanautomatic actuation ofanESFsystem.~rAC~O1rerTATI

'I MACPereM19441LICENSEEEVENTREPORT(LERITEXTCONTINUATION V.l.IIVCLCAA1lQULATOAY COMMI5OQM PAPPAOYlOOMlrrQ)IlQ~IQAl>ceIAlSlrll1$I'ACILITY NAlllIIIQOCKlTHU%%$1lllLIIIMVeell1Illj~OvlrrerALrrlvleIorrA~AOllllR.E.GinnaNuclearPowerPlantTlxTIA'~r~.~ereereMIeIACPerrrr~'llIITIosooo24491-0-9-007os09Anassessment wasperformed considering boththesafetyconsequences andimplications ofthiseventwiththefollowing resultsandconclusions:

Therewerenooperational orsafetyconsequences orimplications attributed tothefeedwater isolations because:oThefeedwater isolations occurredattherequiredS/Glevels.oTheplantwasquicklystabilized andmanualcontroloftheFRVswasaccomplished tomitigatethetransient.

oAsthefeedwater

'solation occurredasdesigned, theassumptions oftheFSARforsteamlinebreakweremet.Basedontheabove,-itcanbeconcluded thatthepublic'shealthandsafetywereassuredatalltimes.V.CORRECTIVE ACTIONA.ACTIONTAKENTORETURNAFFECTEDSYSTEMSTOPRE-EVIBFZ NORMALSTATUS:0TheDieselFirePumpwastemporarily removedfromservicependingtheoutcomeofrootcausetroubleshooting anddetermination.

(Thepumpwasreturnedtoserviceafteranoisesuppression diodewasinstalled acrossrelayAR80).0WhenS/Glevelswerestabilized, subsequent totheADFCSperturbation termination, theFRVswereplacedinautomatic control.0Aftertheplanthadbeenstabilized andtheFRVsreturnedtoautomatic control,thecondensate lowpressureheaterbypassvalvewasclosed,thecondensate boosterpumpswererestoredandthestandbycondensate pumpwassecuredandrealigned forautomatic standby.rrACPOAMel4ll

NAC1vv~(~ILICENSEEEVENTREPORTILER)TEXTCONTINUATION-U,S,NUCLTAAAIOULATOAV COMAIITSION A>>AOVlOOUINO)1$0&I04TIct<ACS~IlI'l$FACILITYNAIACIIIOOCAtTNU~tAIllLtANLAA4IAIIIT~OVINTIALv1AAVISlONA~AOIIlIR.E.GinnaNuclearPowerPlantTerrIA~>>A>>A~.~>>>>VV>>VNACAV>>~SUIITIo5oo'o24491-009-0008DFO9B.ACTIONTAKENORPLANNEDTOPREVENTRECURE&NCE:

o*Areverse-biased diodewastemporarily installed acrossthecoilofAR80onNovember15,1991andsubsequent testingdetermined thatthespikesfromtheAR80circuit,affecting ADFCSfeedwater pressureinputsfollowing dieselfirepump,starts,wereeliminated.

Thisnoisesuppression diode'waspermanently installed onNovember18,1991.Afterreviewing theresultsoftroubleshooting andthediscussion withWestinghouse, thefollowing isanoutlineofthecorrective actionsbeingtakenorplannedinresponsetotheADFCSnoisespikingevents:oShortTermResponsea)Operations personnel weremadeawarethatonesourceofspikesonADFCSwaseliminated, butthatspikesfromothersources,whilereducedinfrequency.

andmagnitude, mightoccur.Operations willidentifyanynewspikesontheADFCSbysubmitting aWorkRequest/Trouble Report(WR/TR).b)AWR/TRwassubmitted forinstallation ofadiodeforthefireboosterpumprelayAR85(whichalsoproducessmallspikesonADFCS).However,thesespikesarenotofthesamemagnitude asthenoisespikesthatwerecausedbytheDieselFirePumpstarts.oIntermediate TermResponseElectrical Engineering willconsultwithWestinghouse concerning adatabasechangetoincreasetheADFCSslewratefilterconstant.

Thisfilterisusedtodampenanyabruptchangestofeedwater regulating valvedemandintheeventthatfeedwater headerpressureinputvaluesarerejectedduetonoisespikes.ItisthoughtNACIOAVTAAA~T4ll

NIICformSOSA(04SISACILITYNASIEIllLICENSEEEVENTREPORTILERITEXTCONTINUATION COCKETNUIAOEII(ElU.E,NUCLEA(lAECULATOAY COSSSIIS3(ON ASSAOYEOOUINOTISOW(04fExs(RES'S(SI'ESLE(iNUIAOEAI~I$SCUSNTrAL osvrsrorr NONvmO~ACE(j(R.E.GinnaNuclearPowerPlantTExT(rfmoroA(sosrsrosrrsos, omsNsooonor (Y(lcform~'ll(illosooo24491-009-0009OF09thatthisfiltercanalso"LockIn"anerroneous valuefollowing afeedwater headeipressurespike.Increasing thisconstantwillmorequicklyrestoreacorrectvalueforfeedwater headerpressure, afteraspikehasdecayed.Thespikeslastlessthanfive(5)seconds.oLongTermResponsea)b)Electrical Engineering willcheckwithWestinghouse fortheresultsoftheirreviewofADFCSarbitration errorcheckingsoftware.

Thisreviewwilldetermine iftheerrorcheckingroutinefortheswitching toarbitration valuesinsteadoffeedwater headerpressurefieldinputvaluesissubstituting erroneous valuesforfeedwater headerpressureusedinFRVdemandcalculations.

Electrical Engineering willevaluatetheroutingoffeedwater headerpressureinputcircuits(tothe-ADFCS),andwillidentifyanyadditional modifications thatmayberequiredtoeliminate theelectromagnetic noisespikeconcern.VX.ADDITXONAL NFORMATION A.FAILEDCOMPONENTS:

NoneB.PREVIOUSLERsONSIMILAREVENTS:AsimilarLEReventhistorical searchwasconducted withthefollowing results:.Nodocumentation ofimilarLEReventswiththesamerootcausecouldbe.identified.

C.SPECIALCO~BFZS:None.NACs01loSSOArS4TI

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