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{{#Wiki_filter:ACCELERATEDDISTRIBUTIONDEMON~0TIONSYSTEMREGULATORYINFORMATIONDISTRIBUTIONSYSTEM(RIDS)ACCESSIONNBR:9108050066DOC.DATE:91/07/29NOTARIZED:,NOFACIL:50-244RobertEmmetGinnaNuclearPlant,Unit1,,RochesterGAUTH.NAMEAUTHORAFFILIATION.BACKUS,W.H.RochesterGas&ElectricCorp.MECREDY,R.C.'ochesterGas&ElectricCorp.RECIP.NAMERECIPIENTAFFILIATIONDOCKET05000244II
{{#Wiki_filter:ACCELERATED DISTRIBUTION DEMON~0TIONSYSTEMREGULATORY INFORMATION DISTRIBUTION SYSTEM(RIDS)ACCESSION NBR:9108050066 DOC.DATE:
91/07/29NOTARIZED:,
NOFACIL:50-244 RobertEmmetGinnaNuclearPlant,Unit1,,Rochester GAUTH.NAMEAUTHORAFFILIATION
.BACKUS,W.H.
Rochester Gas&ElectricCorp.MECREDY,R.C.
'ochester Gas&ElectricCorp.RECIP.NAME RECIPIENT AFFILIATION DOCKET05000244II


==SUBJECT:==
==SUBJECT:==
LER91-006-00:on910629,EDGAstartedautomaticallyduetoapparentundervoltagesignalfromBus14undervoltagemonitoringsys.Rootcausenotdetermined.Bus14energized&EDGdeclaredoperable.W/910729ltr.DISTRIBUTIONCODE:IE22TCOPIESRECEIVED:LTR!ENCLISIZE:7TITLE:50.73/50.9LicenseeEventReport(LER),IncidentRpt,etc.NOTES:LicenseExpdateinaccordancewith10CFR2,2.109(9/19/72).D05000244ARECIPIENTIDCODE/NAMEPD1-3LAJOHNSON,AINTERNAL:ACNWAEOD/DSP/TPABNRR/DET/ECMB9HNRR/DLPQ/LHFB10NRR/DOEA/OEABNRR/DST/SELBSDNRRfDST~LBSD1REGF~02RGN1FILE01EXTERNAL:EG&GBRYCE,J.HNRCPDRNSICPOORE,W.~7&75Htt<w'(COPIESLTTRENCL111122111111111111111'1331111RECIPIENTIDCODE/NAMEPD1-3PDAEOD/DOAAEOD/ROAB/DSPNRR/DET/EMEB7ENRR/DLPQ/LPEB10NRR/DREP/PRPB11NRR/DST/SICBSH3NRR/DST/SRXBSERES/DSIR/EIBLSTLOBBYWARDNSICMURPHY,G.ANUDOCSFULLTXT'OPIESLTTRENCL111122111122111'11111111DDDNOTETOALL"RIDS"RECIPIENTS:PLEASEHELPUSTOREDUCEWASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROOiv!P1-37(EXT.20079)TOELIMINATEYOURNAMEFROMDISTRIBUTIONLISTSFORDOCU5!EiiTSYOUDON'TNEED!ADDSFULLTEXTCONVERSIONREQUIRED-TOTALNUMBEROFCOPIESREQUIRED:LTTR31ENCL31  
LER91-006-00:on 910629,EDG Astartedautomatically duetoapparentundervoltage signalfromBus14undervoltage monitoring sys.Rootcausenotdetermined.Bus 14energized
&EDGdeclaredoperable.W/910729 ltr.DISTRIBUTION CODE:IE22TCOPIESRECEIVED:LTR
!ENCLISIZE:7TITLE:50.73/50.9 LicenseeEventReport(LER),IncidentRpt,etc.NOTES:License Expdateinaccordance with10CFR2,2.109(9/19/72).
D05000244ARECIPIENT IDCODE/NAME PD1-3LAJOHNSON,A INTERNAL:
ACNWAEOD/DSP/TPAB NRR/DET/ECMB 9HNRR/DLPQ/LHFB10 NRR/DOEA/OEAB NRR/DST/SELB SDNRRfDST~LBSD1 REGF~02RGN1FILE01EXTERNAL:
EG&GBRYCE,J.H NRCPDRNSICPOORE,W.~7&75Htt<w'(COPIESLTTRENCL111122111111111111111'1331111RECIPIENT IDCODE/NAME PD1-3PDAEOD/DOAAEOD/ROAB/DSP NRR/DET/EMEB 7ENRR/DLPQ/LPEB10 NRR/DREP/PRPB11 NRR/DST/SICBSH3 NRR/DST/SRXB SERES/DSIR/EIB LSTLOBBYWARDNSICMURPHY,G.A NUDOCSFULLTXT'OPIES LTTRENCL111122111122111'11111111DDDNOTETOALL"RIDS"RECIPIENTS:
PLEASEHELPUSTOREDUCEWASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROOiv!P1-37(EXT.20079)TOELIMINATE YOURNAMEFROMDISTRIBUTION LISTSFORDOCU5!EiiTS YOUDON'TNEED!ADDSFULLTEXTCONVERSION REQUIRED-TOTALNUMBEROFCOPIESREQUIRED:
LTTR31ENCL31  
~Oo  
~Oo  
)rf/rrrritiirpdtisu'ift'rrlIr'!i!""/I'.;,rrrtii","ROCHESTERGASANDELECTRICCORPORATIONROSERTCh1ECREDYVicePresidentCtnnaNucfearPrnducticrnoe'I'a','','~1th~~'rStale.,89EASTAVENUE,ROCHESTERN.K14649-0001iTELEPHONEAAEACODETIB5462700July29,1991IU.S.NuclearRegulatoryCommissionDocumentControlDeskWashington,-DC20555
)rf/rrrritiirpdtisu'ift'rrlIr'!i!
""/I'.;,rrrtii
","ROCHESTER GASANDELECTRICCORPORATION ROSERTCh1ECREDYVicePresident CtnnaNucfearPrnducticrn oe'I'a','','
~1th~~'rStale.,89EASTAVENUE,ROCHESTER N.K14649-0001 iTELEPHONE AAEACODETIB 5462700July29,1991IU.S.NuclearRegulatory Commission DocumentControlDeskWashington,-
DC20555


==Subject:==
==Subject:==
LER91-006,ApparentVoltageDroponSafeguards480VoltBus14CausesanAutomaticStartofthe"A"EmergencyDieselGeneratorR.E.GinnaNuclearPowerPlantDocketNo.50-244In-accordancewith10CFR50.73,LicenseeEventReportSystem,item(a)(2)(iv),whichrequiresareportof,"anyeventorconditionthatresultedinmanualorautomaticactuationofanyEngineeredSafetyFeature(ESF),"includingtheReactorProtectionSystem(RPS)",theattachedLicenseeEventReportLER91-006isherebysubmitted.Thiseventhasinnowayaffectedthepublic'shealthandsafety.Verytrulyyours,RobertC.MecrdyxcU.S.NuclearRegulatoryCommissionRegionI475AllendaleRoadKingofPrussia,PA19406GinnaUSNRCSeniorResidentInspector9i080s00g,(,PDRADOCKOrt.iot)-4i
LER91-006,ApparentVoltageDroponSafeguards 480VoltBus14CausesanAutomatic Startofthe"A"Emergency DieselGenerator R.E.GinnaNuclearPowerPlantDocketNo.50-244In-accordance with10CFR50.73,LicenseeEventReportSystem,item(a)(2)(iv),
whichrequiresareportof,"anyeventorcondition thatresultedinmanualorautomatic actuation ofanyEngineered SafetyFeature(ESF),"including theReactorProtection System(RPS)",theattachedLicenseeEventReportLER91-006isherebysubmitted.
Thiseventhasinnowayaffectedthepublic'shealthandsafety.Verytrulyyours,RobertC.MecrdyxcU.S.NuclearRegulatory Commission RegionI475Allendale RoadKingofPrussia,PA19406GinnaUSNRCSeniorResidentInspector 9i080s00g,(,
PDRADOCKOrt.iot)-4 i


NACtaslliIOACILICENSEEEVENTREPORT(LERIUANUOLCAAAoovLATCAocc>>se&lcwAttleovtooleoNILOINolovCAOIACO.O)te/~$)ACILITYNA<<)OIllR.E.GinnaNuclearPower.PlantOOCACTeeveeoCAOlo6ooo244iosApparentVoltageDmpOnSafequards480VoltBus14CausesanAutomaticStartoftheA"EmerencDieselGeneratorCVCIITCATO14Lt1NveeocA14Al)O1TOATClllOTlet1)ACILITICCINVOLVCOIOI>>OI>>T>>eOAYYCAAYCAA~COveeee>>AL>>eV>>l11NONTNOAYYCAA)ACIUTYMA>>elAOOCACTAve)il1140600O062991910060007299106000Otl1ATIIIOe)OOtNl~OeeCALtvlL0e~r<<jM<+d>>%wII>>".TIIIC1l)01TICVO<<IITTCO)VACVANTTCO.<<OCNICO.<<OOleIIIII~CO.OOOleIllIIIITo.eoc4IIIII>>ITOAOOlelllllleltiOOCI)IIIIIelTt.eotlelNWI)IIIINMNIICIN.TCNI0IION.TC4IItII~IN.T$4IICIIWlN.'IQeIltl(NI=N.TONIICllelN.TONIICIleoIN.TC4IICIleeNW~O.TONIItlIeellICIN.TCNIltlleloTNC1covl1t<<ICNTootIoct1$:lc<<eeo<<eeaoeaoo)o>>Ia>>ooe)I0IT%7141TC.1141OTlet1li)o)OVleAAeoeee~<<o>>e<<tSTe)L<<ACl<<sLICtNCCCCONTACT)OATillLt1Iltl>>A<<etWesleyH.BackusTechnicalAssistanttotheOperationsManagerAIIOACOOlTILC)leONCNVQOCA31524-4446COeetLCTCONCLINC)01CAC>>lCO<<e)ONCNT)AILUACOtlC1IOCOINTNICAtt01TlltlcAvlcCYOTC<<ecoco)oNCNTe)ANvtAcTVACActoATACLC.+:"ke~~+pju>>.~'TOIe)AOC>>Aj~Yn~k,ee>>'~Qg,CAVltCYOTCIIs'>>>>>>'ehv+v;o>>>>~(e>>Q+PP+c~p,COee)ONCNT>>ANVtAC,TUACACV)YLC4CNTALAttOATCA)CCTCOIlel'YCCIIItee,e<<ee<<e>>CA)CCTCOCV)<<IICCIONCATO)XNO<<ACTAAcTIL<<evls1)00eoas,Ieeooeoeeev>>I)III>>oee<<etvvoeeeItoeeee>>I>>o<<esl114t1)CCTCOwo<<elttloNOATCIlllIIONT>>eCAYYCANOnJune29,1991at1754ESTwiththereactoratapproximately98%fullpower,the"A"EmergencyDieselGeneratorstartedautomaticallyduetoanapparentundervoltagesignalfromtheBus14UndervoltageMonitoringSystem.The"A"EmergencyDieselGenerator,afterstarting,attainedpropervoltageandfrequency.Bydesign,itdidnotcloseintoBus14becauseBus14wasatitspropervoltageandbeingfedfromitsnormalpowersupply.ImmediateoperatoractionwastoverifythatBus14wasenergizedandthatthe"A"EmergencyDieselGeneratorwasoperatingnormally.Subsequently)the"A"EmergencyDieselGeneratorwasstoppedandrealignedforauto-standby.Thecauseoftheeventhas.notbeenpositivelydetermined,althoughoff-siteelectricaldisturbanceispostulated.Sincethecauseofthiseventhasnotbeenpositivelydeterminedatthistime,wewillcontinuetoinvestigatefortheunderlyingcause.Anyfurthercorrectiveactionwilldependonthere'suitsofthisinvestigation.eeACtoesONIOACI  
NACtaslliIOACILICENSEEEVENTREPORT(LERIUANUOLCAAAoovLATCAocc>>se&lcw Attleovto oleoNILOINolovCAOIACO.O)te/
~$)ACILITYNA<<)OIllR.E.GinnaNuclearPower.PlantOOCACTeeveeoCAOlo6ooo244ios ApparentVoltageDmpOnSafequards 480VoltBus14CausesanAutomatic StartoftheA"EmerencDieselGenerator CVCIITCATO14Lt1NveeocA14Al)O1TOATClllOTlet1)ACILITICC INVOLVCOIOI>>OI>>T>>eOAYYCAAYCAA~COveeee>>AL
>>eV>>l11NONTNOAYYCAA)ACIUTYMA>>elAOOCACTAve)il1140600O062991910060007299106000Otl1ATIIIOe)OOtNl~OeeCALtvlL0e~r<<jM<+d>>%wII>>".
TIIIC1l)01TICVO<<IITTCO
)VACVANTTCO.<<OCNICO.<<OOleIIIII~CO.OOOleIllIIIITo.eoc4IIIII>>ITOAOOlellllllel tiOOCI)IIIIIelTt.eotlelNWI)IIIINMNIICIN.TCNI0IION.TC4IItII~IN.T$4IICIIWlN.'IQeIltl(NI=N.TONIICllelN.TONIICI leoIN.TC4IICIleeNW
~O.TONIItlIeellICIN.TCNIltllel oTNC1covl1t<<ICNTootIoct1$:lc<<eeo<<eeaoeaoo)o>>Ia>>ooe)I0IT%7141TC.1141OTlet1li)o)OVleAAeoeee~<<o>>e<<tSTe)L<<ACl<<sLICtNCCCCONTACT)OATillLt1Iltl>>A<<etWesleyH.BackusTechnical Assistant totheOperations ManagerAIIOACOOlTILC)leONC NVQOCA31524-4446COeetLCTC ONCLINC)01CAC>>lCO<<e)ONCNT
)AILUACOtlC1IOCO INTNICAtt01TlltlcAvlcCYOTC<<ecoco)oNCNT e)ANvtAcTVACActoATACLC
.+:"ke~~+pju>>.~'TOIe)AOC>>Aj~Yn~k,ee>>'~Qg, CAVltCYOTCIIs'>>>>>>'ehv+v;o>>>>~(e>>Q+PP+c~p, COee)ONCNT>>ANVtAC,TUACACV)YLC4CNTAL AttOATCA)CCTCOIlel'YCCIIItee,e<<ee<<e>>CA)CCTCOCV)<<IICCION CATO)XNO<<ACTAAcTIL<<evls1)00eoas,Ieeooeoeeev>>I)
III>>oee<<etvvoeee Itoeeee>>I>>o
<<esl114t1)CCTCOwo<<elttloN OATCIlllIIONT>>eCAYYCANOnJune29,1991at1754ESTwiththereactoratapproximately 98%fullpower,the"A"Emergency DieselGenerator startedautomatically duetoanapparentundervoltage signalfromtheBus14Undervoltage Monitoring System.The"A"Emergency DieselGenerator, afterstarting, attainedpropervoltageandfrequency.
Bydesign,itdidnotcloseintoBus14becauseBus14wasatitspropervoltageandbeingfedfromitsnormalpowersupply.Immediate operatoractionwastoverifythatBus14wasenergized andthatthe"A"Emergency DieselGenerator wasoperating normally.
Subsequently) the"A"Emergency DieselGenerator wasstoppedandrealigned forauto-standby.
Thecauseoftheeventhas.notbeenpositively determined, althoughoff-siteelectrical disturbance ispostulated.
Sincethecauseofthiseventhasnotbeenpositively determined atthistime,wewillcontinuetoinvestigate fortheunderlying cause.Anyfurthercorrective actionwilldependonthere'suitsofthisinvestigation.
eeACtoesONIOACI  
~0~0  
~0~0  
~e~H(ICFMmdddA(045)L'ICENSEEEVENTREPORTILERITEXTCONTINUATION3U.d.HUCLCA(IHKOULATOHYCOMM(dd(OHAFFHOVEOOMdHO5150M(04dkF(Added(5((55FACILITYHAMd(IIR.E.GinnaNuclearPowerPlantTEXTIN'cccMcccHmdvckd.vccNMcckncc(4(NCFckmJ(d(4'cl((T(OOC((ETHUMddll(1(0s00024491Ld(IHUMddll(dl5~OVCHZIAL4HVMk-006kdVMIOHHUM0FAOd(5102DFO6PRE-EVE2iTPLANTCONDITIONSTheplantwasatapproximately984steadystatefullpowerwithno'ajoractivitiesinprogress.II.DESCRIPTIONOF%TENTA.DATESANDAPPROXIMATETIMESOPMAJOROCCURRENCES:000June29,1991,1754EDST:EventDateandTimehJune29,1991,1754EDST:DiscoveryDateandTimeJune29,1991,2013EDST:"A"EmergencyDieselGeneratorstoppedandrealignedforAuto-standbyB.EVENT:OnJune29,1991at1754EDST,withthereactoratapproximately98%fullpower,theControlRoomreceivedthefollowingalarms:L-14(Bus14.Undervoltage-Safeguards)andJ-24(EmergencyDieselGen1APanel).TheControlRoomoperatorsimmediatelyverifiedpropervoltageonBus14andthatthenormalpowersupplybreakerwasclosed.TheControlRoomoperatorsalsoverifiedthatthe"A"EmergencyDieselGeneratorhadstartedanddisplayedpropervoltageandfrequency.Bydesign,the"A"EmergencyDieselGeneratordidnotcloseintoBus,14,asthebusvoltagewasnormalandBus14wasstillbeingsuppliedbyitsnormalpowersupply.HACFOAM544*(Iddl  
~e~H(ICFMmdddA(045)L'ICENSEE EVENTREPORTILERITEXTCONTINUATION 3U.d.HUCLCA(IHKOULATOHY COMM(dd(OH AFFHOVEOOMdHO5150M(04dkF(Added(5((55 FACILITYHAMd(IIR.E.GinnaNuclearPowerPlantTEXTIN'cccMcccHmdvckd.vccNMcckncc(
4(NCFckmJ(d(4'cl((T(OOC((ETHUMddll(1(0s00024491Ld(IHUMddll(dl5~OVCHZIAL4HVMk-006kdVMIOHHUM0FAOd(5102DFO6PRE-EVE2iT PLANTCONDITIONS Theplantwasatapproximately 984steadystatefullpowerwithno'ajoractivities inprogress.
II.DESCRIPTION OF%TENTA.DATESANDAPPROXIMATE TIMESOPMAJOROCCURRENCES:
000June29,1991,1754EDST:EventDateandTimehJune29,1991,1754EDST:Discovery DateandTimeJune29,1991,2013EDST:"A"Emergency DieselGenerator stoppedandrealigned forAuto-standby B.EVENT:OnJune29,1991at1754EDST,withthereactoratapproximately 98%fullpower,theControlRoomreceivedthefollowing alarms:L-14(Bus14.Undervoltage
-Safeguards) andJ-24(Emergency DieselGen1APanel).TheControlRoomoperators immediately verifiedpropervoltageonBus14andthatthenormalpowersupplybreakerwasclosed.TheControlRoomoperators alsoverifiedthatthe"A"Emergency DieselGenerator hadstartedanddisplayed propervoltageandfrequency.
Bydesign,the"A"Emergency DieselGenerator didnotcloseintoBus,14,asthebusvoltagewasnormalandBus14wasstillbeingsuppliedbyitsnormalpowersupply.HACFOAM544*(Iddl  
~0  
~0  
~0~eNRCSotw295A(042IL'ICENSEEEVENTREPORTILERITEXTCONTINUATIONU.S.NUCLEARREQVLATORYCOMMI55IONASSROVEOOM9NOSISOWI04JEXSIRES,9121/99SACILITYNAME111OOCKETNVMEER121LERNVMQEII19155QUENTIALNUMREVISIONNUMSAOEl21R.E.GinnaNuclearPowerPlantTEXTIIJ~<<>>5~N~.v>>NAS55JNJHRCFOnn2OEA'5IIITIo5ooo244,0060003pF06Subsequently,AuxiliaryoperatorsweredispatchedtochecktheBus14UndervoltageMonitoringSystemcabinetsandtheoperationofthe"A"EmergencyDieselGenerator.Theoperationofthe"A"EmergencyDieselGeneratorwasfoundtobenormal.NoundervoltagetriptargetswereobservedonBus14orBus18(boththesebusesarefedbythe"A"Emergency.DieselGenerator).Duringthisevent,routineactivitieswereoccurringatoff-siteStation204.AtapproximatelythesametimeastheapparentundervoltageconditionoccurredonBus14,a34.5kvcapacitorbankwasbeingremovedfromservice.Thisisaroutineactiontocorrectoff-sitevoltagesituations.Station204'eedsCircuit751,whichwasthenormaloff-sitepowersupplytoBuses14and18.Control=RoomoperatorsnotifiedhighersupervisionandtheNuclearRegulatoryCommissionoftheevent.ToproveoperabilityoftheUndervoltageMonitoringSystem,theResultsandTest(R&T)DepartmentperformedPeriodicTestprocedurePT-9.1(UndervoltageProtection480VoltSafeguardsBusses)onBus14.AfterPT-9.1.wassuccessfullycompleted,the"A"EmergencyDieselGeneratorwasstoppedandrealignedforAuto-standby.C.INOPERABLESTRUC'HIRES,COMPONENTSsORSYSTEMSTHATCONTRIBUTEDTOTHEEVENT:None.D.OTEGsRSYSTEMSORSECONDARYPUNCTIONSAFFECTED:E.None.METHODOPDISCOVERY:TheeventswereimmediatelyapparentduetoalarmsandindicationsintheControlRoom.NRCSORM255AI94ll  
~0~eNRCSotw295A(042IL'ICENSEE EVENTREPORTILERITEXTCONTINUATION U.S.NUCLEARREQVLATORY COMMI55ION ASSROVEOOM9NOSISOWI04JEXSIRES,9121/99SACILITYNAME111OOCKETNVMEER121LERNVMQEII19155QUENTIAL NUMREVISIONNUMSAOEl21R.E.GinnaNuclearPowerPlantTEXTIIJ~<<>>5~N~.v>>NAS55JNJHRCFOnn2OEA'5IIITIo5ooo244,0060003pF06Subsequently, Auxiliary operators weredispatched tochecktheBus14Undervoltage Monitoring Systemcabinetsandtheoperation ofthe"A"Emergency DieselGenerator.
Theoperation ofthe"A"Emergency DieselGenerator wasfoundtobenormal.Noundervoltage triptargetswereobservedonBus14orBus18(boththesebusesarefedbythe"A"Emergency
.DieselGenerator).
Duringthisevent,routineactivities wereoccurring atoff-siteStation204.Atapproximately thesametimeastheapparentundervoltage condition occurredonBus14,a34.5kvcapacitor bankwasbeingremovedfromservice.Thisisaroutineactiontocorrectoff-sitevoltagesituations.
Station204'eedsCircuit751,whichwasthenormaloff-sitepowersupplytoBuses14and18.Control=Roomoperators notifiedhighersupervision andtheNuclearRegulatory Commission oftheevent.Toproveoperability oftheUndervoltage Monitoring System,theResultsandTest(R&T)Department performed PeriodicTestprocedure PT-9.1(Undervoltage Protection 480VoltSafeguards Busses)onBus14.AfterPT-9.1.wassuccessfully completed, the"A"Emergency DieselGenerator wasstoppedandrealigned forAuto-standby.
C.INOPERABLE STRUC'HIRES, COMPONENTS sORSYSTEMSTHATCONTRIBUTED TOTHEEVENT:None.D.OTEGsRSYSTEMSORSECONDARY PUNCTIONS AFFECTED:
E.None.METHODOPDISCOVERY:
Theeventswereimmediately apparentduetoalarmsandindications intheControlRoom.NRCSORM255AI94ll  
.OO  
.OO  
<<ACSottoSSSA~eL'ICENSEEEVENTREPORT(LER)TEXTCONTINUATIONV,S.<<UCLEAIIIlfOULATOIIYCOMMISSIOIIASSAOYEOOMSHO3150MIOIIEXSIAES,SISIl95SACILITYNAMEIllR.E.GinnaNuclearPowerPlantTEXTillnave<<WCe<<nquseCvASOdakevWlYPCArm~'llIITIOOCKETIIUMSEII11Iosooo24LEII<<UMSEIIISI5~4UC<<VIAL'SV<<IONHUM<<'"<<UMf<<9-1-006-00~AOSISI04o~06F.OPERATORACTXON:FollowingtheBus14UndervoltageAlarmandthe"A"EmergencyDieselGeneratorautomaticstart,theCo'ntrolRoomoperatorsimmediatelyverifiedpropervoltageonBus14viathenormalpowersupplyand',thatthe"A"EmergencyDieselGeneratordisplayedpropervoltageandfrequency.Subsequently,Auxiliaryoperatorsweredis'patchedtocheck-theBus14undervoltagemonitoringsystemand"A"EmergencyDieselGeneratoroperation.The"A"EmergencyDieselGeneratoroperationwasnormaland,noundervoltagetriptargetswereobservedonBus14orBus18.'t"The"A"EmergencyDieselGeneratorwassubsequentlystoppedandrealignedforAuto-standby.G.SAFETXSXSTEMRESPONSES:The"A"EmergencyDieselGeneratorautomaticallystartedanddisplayedpropervoltageandfrequency.'IXI.CAUSEOFEV19Fl'.XMM1sDIATECAUSE:Theautomaticactuationofthe-"A"EmergencyDieselGeneratorwasduetoanapparentundervoltagesignalfromtheBus14undervoltagemonitoringsystem.B.ROOTCAUSE:Theunderlying,causeoftheapparentundervoltagesignalfromtheBus14undervoltagemonitoringsystemisnotpositivelydeterminedatthistime..MACSO<<MSSSAI941l  
<<ACSottoSSSA~eL'ICENSEE EVENTREPORT(LER)TEXTCONTINUATION V,S.<<UCLEAIIIlfOULATOIIY COMMISSIOII ASSAOYEOOMSHO3150MIOIIEXSIAES,SISIl95SACILITYNAMEIllR.E.GinnaNuclearPowerPlantTEXTillnave<<WCe<<nquseCvASOdakevWlYPCArm~'llIITIOOCKETIIUMSEII11Iosooo24LEII<<UMSEIIISI5~4UC<<VIAL'SV<<IONHUM<<'"<<UMf<<9-1-006-00~AOSISI04o~06F.OPERATORACTXON:Following theBus14Undervoltage Alarmandthe"A"Emergency DieselGenerator automatic start,theCo'ntrolRoomoperators immediately verifiedpropervoltageonBus14viathenormalpowersupplyand',thatthe"A"Emergency DieselGenerator displayed propervoltageandfrequency.
~0 IIACSovvvv444A14451~eoeL'ICENSEEEVENTREPORT(LERITEXTCONTINUATIONU,E.NUCLEAAAEOULATOAYCOMMIEEIOII/ASSAOVEOOMEIVO1150MIOeEXSIAES,4151/45SACILITYIIAMEIllR.E.GinnaNuclearPawerPlantTExTlllnaveMeceaeevveevLvvMvneeevalvYACSevvnSELAYlIITICOCKETIvUMEEA111osooo244vEAALEIIIIUMEEA14154004VVTIAL~VUM006ntvlelOMVVVM00SAOEIEI050F06IV.ANALYSISOFEVENTTheeventisreportableinaccordancewith10CFR50.73,LicenseeEventReportSystem,item(a)(2)(iv),whichrequires'eportingof,"anyeventorconditionthatresultedinmanualorautomaticactuationofanyEngineeredSafetyFeature(ESF)includingtheReactor.ProtectionSystem(RPS)".Thestartingofthe"A"EmergencyDieselGeneratorwasanautomaticactuationofanESFsystem.Anassessmentwasperformedconsideringboththesafetyconsequencesandimplicationsofthiseventwiththefollowingresultsandconclusions:Therewerenooperationalorsafetyconsequencesorimplicationsattributedtothestartingofthe"A"EmergencyDieselGeneratorbecause:0The"A"EmergencyDieselGeneratoroperatedasdesigned.oBothBus14powersupplies(i.e.normalandemergency)wereeitherinuseoravailablethroughouttheevent.oTheBus14undervoltagemonitoringsystemoperationwasintheconservativedirection,(i.e.theoperationactuatedtheautomaticstartofthe"A"EmergencyDieselGenerator).Basedontheabove,itcanbeconcludedthatthepublic'shealthandsafetywasassuredatalltimes.V.CORRECTIVEACTIONA.ACTIONTAKENTORETURNAFFECTEDSYSTEMSTOPRE-EVENTNORMALSTATUS:oTheR&TDepartmentsuccessfullycompletedPT-9.1onBus14andthe"A"EmergencyDieselGeneratorwasstoppedandalignedforAuto-standby.~VACS0VIM544A14411  
Subsequently, Auxiliary operators weredis'patched tocheck-theBus14undervoltage monitoring systemand"A"Emergency DieselGenerator operation.
~1~0 NAC>armSEEAIHEI~0I.'ICENSEEEVENTREPORT(I.ER)TEXTCONTINUATIONV.S.NVCLEAIIIIEOVLATOIIYCOMMISSIONIAtfAOVEOOMEHO$1$0MIOIE)CrllIES.EISI4$FACILITYNAMEIIIOOCIIETNVMEEIIIEIYEAALEIINVMEEIIIEIIEQVEHTIAL4MIAAEVISIO<NVMIA~ACEISIR.E.GinnaNuclearPowerPlantTEILillmortapeceemewaf.wtaAkenVHACFiwnDELI'IlIITlosooo.244910060006'F06B.ACTXONTAKENORPLANNEDTOPREVENTRECURRENCE:000Astheunderlyingcauseoftheeventhasnotbeendeterminedatthistime,investigationswillcontinuetopositivelydeterminetheunderlyingcauseofthisevent.Anyfurthercorrectiveactionswilldependontheresultsoftheseinvestigations.Electricalsystemmonitoringrecordshavebeenreviewed,andindicatethatremovalofthecapacitorbankresultedinasmallandroutinevoltagetransient.ElectricalsystemmonitoringhasbeenincreasedonCircuit751.0Theinterfacebetweentheundervoltagemonitoringsystemanddieselstartcircuitrywillcontinuetobeevaluated,'todetermineiftheundervoltagesystemisreactingasdesignedforsmallvoltagefluctuations.ADDXTXONALXNFORMATIONA.B.PAXLEDCOMPONENTS:None.PREVXOUSLERsONSIMILAREVENTS:AsimilarLEReventhistoricalsearchwasconductedwiththefollowingresults:NodocumentationofsimilarLEReventswithanundeterminedrootcauseatGinnaStationcouldbeidentified.C.SPECIALCOMMENTSNone.%ACSOIIMSEEAISAl  
The"A"Emergency DieselGenerator operation wasnormaland,noundervoltage triptargetswereobservedonBus14orBus18.'t"The"A"Emergency DieselGenerator wassubsequently stoppedandrealigned forAuto-standby.
G.SAFETXSXSTEMRESPONSES:
The"A"Emergency DieselGenerator automatically startedanddisplayed propervoltageandfrequency.
'IXI.CAUSEOFEV19Fl'.XMM1sDIATE CAUSE:Theautomatic actuation ofthe-"A"Emergency DieselGenerator wasduetoanapparentundervoltage signalfromtheBus14undervoltage monitoring system.B.ROOTCAUSE:Theunderlying, causeoftheapparentundervoltage signalfromtheBus14undervoltage monitoring systemisnotpositively determined atthistime..MACSO<<MSSSAI941l  
~0 IIACSovvvv444A14451~eoeL'ICENSEE EVENTREPORT(LERITEXTCONTINUATION U,E.NUCLEAAAEOULATOAY COMMIEEIOII
/ASSAOVEOOMEIVO1150MIOeEXSIAES,4151/45SACILITYIIAMEIllR.E.GinnaNuclearPawerPlantTExTlllnaveMeceaeevveevLvvMvneeevalvYACSevvnSELAYlIITICOCKETIvUMEEA111osooo244vEAALEIIIIUMEEA14154004VVTIAL~VUM006ntvlelOMVVVM00SAOEIEI050F06IV.ANALYSISOFEVENTTheeventisreportable inaccordance with10CFR50.73,LicenseeEventReportSystem,item(a)(2)(iv),
whichrequires'eporting of,"anyeventorcondition thatresultedinmanualorautomatic actuation ofanyEngineered SafetyFeature(ESF)including theReactor.Protection System(RPS)".Thestartingofthe"A"Emergency DieselGenerator wasanautomatic actuation ofanESFsystem.Anassessment wasperformed considering boththesafetyconsequences andimplications ofthiseventwiththefollowing resultsandconclusions:
Therewerenooperational orsafetyconsequences orimplications attributed tothestartingofthe"A"Emergency DieselGenerator because:0The"A"Emergency DieselGenerator operatedasdesigned.
oBothBus14powersupplies(i.e.normalandemergency) wereeitherinuseoravailable throughout theevent.oTheBus14undervoltage monitoring systemoperation wasintheconservative direction, (i.e.theoperation actuatedtheautomatic startofthe"A"Emergency DieselGenerator).
Basedontheabove,itcanbeconcluded thatthepublic'shealthandsafetywasassuredatalltimes.V.CORRECTIVE ACTIONA.ACTIONTAKENTORETURNAFFECTEDSYSTEMSTOPRE-EVENT NORMALSTATUS:oTheR&TDepartment successfully completed PT-9.1onBus14andthe"A"Emergency DieselGenerator wasstoppedandalignedforAuto-standby.
~VACS0VIM544A14411  
~1~0 NAC>armSEEAIHEI~0I.'ICENSEE EVENTREPORT(I.ER)TEXTCONTINUATION V.S.NVCLEAIIIIEOVLATOIIY COMMISSION IAtfAOVEOOMEHO$1$0MIOIE)CrllIES.
EISI4$FACILITYNAMEIIIOOCIIETNVMEEIIIEIYEAALEIINVMEEIIIEIIEQVEHTIAL 4MIAAEVISIO<NVMIA~ACEISIR.E.GinnaNuclearPowerPlantTEILillmortapeceemewaf.wtaAkenVHACFiwnDELI'IlIITlosooo.244910060006'F06B.ACTXONTAKENORPLANNEDTOPREVENTRECURRENCE:
000Astheunderlying causeoftheeventhasnotbeendetermined atthistime,investigations willcontinuetopositively determine theunderlying causeofthisevent.Anyfurthercorrective actionswilldependontheresultsoftheseinvestigations.
Electrical systemmonitoring recordshavebeenreviewed, andindicatethatremovalofthecapacitor bankresultedinasmallandroutinevoltagetransient.
Electrical systemmonitoring hasbeenincreased onCircuit751.0Theinterface betweentheundervoltage monitoring systemanddieselstartcircuitry willcontinuetobeevaluated,'to determine iftheundervoltage systemisreactingasdesignedforsmallvoltagefluctuations.
ADDXTXONAL XNFORMATION A.B.PAXLEDCOMPONENTS:
None.PREVXOUSLERsONSIMILAREVENTS:AsimilarLEReventhistorical searchwasconducted withthefollowing results:Nodocumentation ofsimilarLEReventswithanundetermined rootcauseatGinnaStationcouldbeidentified.
C.SPECIALCOMMENTSNone.%ACSOIIMSEEAISAl  
~01~f}}
~01~f}}

Revision as of 12:11, 29 June 2018

LER 91-006-00:on 910629,EDG a Started Automatically Due to Apparent Undervoltage Signal from Bus 14 Undervoltage Monitoring Sys.Root Cause Not Determined.Bus 14 Energized & EDG Declared operable.W/910729 Ltr
ML17262A566
Person / Time
Site: Ginna Constellation icon.png
Issue date: 07/29/1991
From: BACKUS W H, MECREDY R C
ROCHESTER GAS & ELECTRIC CORP.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-91-006, LER-91-6, NUDOCS 9108050066
Download: ML17262A566 (16)


Text

ACCELERATED DISTRIBUTION DEMON~0TIONSYSTEMREGULATORY INFORMATION DISTRIBUTION SYSTEM(RIDS)ACCESSION NBR:9108050066 DOC.DATE:

91/07/29NOTARIZED:,

NOFACIL:50-244 RobertEmmetGinnaNuclearPlant,Unit1,,Rochester GAUTH.NAMEAUTHORAFFILIATION

.BACKUS,W.H.

Rochester Gas&ElectricCorp.MECREDY,R.C.

'ochester Gas&ElectricCorp.RECIP.NAME RECIPIENT AFFILIATION DOCKET05000244II

SUBJECT:

LER91-006-00:on 910629,EDG Astartedautomatically duetoapparentundervoltage signalfromBus14undervoltage monitoring sys.Rootcausenotdetermined.Bus 14energized

&EDGdeclaredoperable.W/910729 ltr.DISTRIBUTION CODE:IE22TCOPIESRECEIVED:LTR

!ENCLISIZE:7TITLE:50.73/50.9 LicenseeEventReport(LER),IncidentRpt,etc.NOTES:License Expdateinaccordance with10CFR2,2.109(9/19/72).

D05000244ARECIPIENT IDCODE/NAME PD1-3LAJOHNSON,A INTERNAL:

ACNWAEOD/DSP/TPAB NRR/DET/ECMB 9HNRR/DLPQ/LHFB10 NRR/DOEA/OEAB NRR/DST/SELB SDNRRfDST~LBSD1 REGF~02RGN1FILE01EXTERNAL:

EG&GBRYCE,J.H NRCPDRNSICPOORE,W.~7&75Htt<w'(COPIESLTTRENCL111122111111111111111'1331111RECIPIENT IDCODE/NAME PD1-3PDAEOD/DOAAEOD/ROAB/DSP NRR/DET/EMEB 7ENRR/DLPQ/LPEB10 NRR/DREP/PRPB11 NRR/DST/SICBSH3 NRR/DST/SRXB SERES/DSIR/EIB LSTLOBBYWARDNSICMURPHY,G.A NUDOCSFULLTXT'OPIES LTTRENCL111122111122111'11111111DDDNOTETOALL"RIDS"RECIPIENTS:

PLEASEHELPUSTOREDUCEWASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROOiv!P1-37(EXT.20079)TOELIMINATE YOURNAMEFROMDISTRIBUTION LISTSFORDOCU5!EiiTS YOUDON'TNEED!ADDSFULLTEXTCONVERSION REQUIRED-TOTALNUMBEROFCOPIESREQUIRED:

LTTR31ENCL31

~Oo

)rf/rrrritiirpdtisu'ift'rrlIr'!i!

""/I'.;,rrrtii

","ROCHESTER GASANDELECTRICCORPORATION ROSERTCh1ECREDYVicePresident CtnnaNucfearPrnducticrn oe'I'a',,'

~1th~~'rStale.,89EASTAVENUE,ROCHESTER N.K14649-0001 iTELEPHONE AAEACODETIB 5462700July29,1991IU.S.NuclearRegulatory Commission DocumentControlDeskWashington,-

DC20555

Subject:

LER91-006,ApparentVoltageDroponSafeguards 480VoltBus14CausesanAutomatic Startofthe"A"Emergency DieselGenerator R.E.GinnaNuclearPowerPlantDocketNo.50-244In-accordance with10CFR50.73,LicenseeEventReportSystem,item(a)(2)(iv),

whichrequiresareportof,"anyeventorcondition thatresultedinmanualorautomatic actuation ofanyEngineered SafetyFeature(ESF),"including theReactorProtection System(RPS)",theattachedLicenseeEventReportLER91-006isherebysubmitted.

Thiseventhasinnowayaffectedthepublic'shealthandsafety.Verytrulyyours,RobertC.MecrdyxcU.S.NuclearRegulatory Commission RegionI475Allendale RoadKingofPrussia,PA19406GinnaUSNRCSeniorResidentInspector 9i080s00g,(,

PDRADOCKOrt.iot)-4 i

NACtaslliIOACILICENSEEEVENTREPORT(LERIUANUOLCAAAoovLATCAocc>>se&lcw Attleovto oleoNILOINolovCAOIACO.O)te/

~$)ACILITYNA<<)OIllR.E.GinnaNuclearPower.PlantOOCACTeeveeoCAOlo6ooo244ios ApparentVoltageDmpOnSafequards 480VoltBus14CausesanAutomatic StartoftheA"EmerencDieselGenerator CVCIITCATO14Lt1NveeocA14Al)O1TOATClllOTlet1)ACILITICC INVOLVCOIOI>>OI>>T>>eOAYYCAAYCAA~COveeee>>AL

>>eV>>l11NONTNOAYYCAA)ACIUTYMA>>elAOOCACTAve)il1140600O062991910060007299106000Otl1ATIIIOe)OOtNl~OeeCALtvlL0e~r<<jM<+d>>%wII>>".

TIIIC1l)01TICVO<<IITTCO

)VACVANTTCO.<<OCNICO.<<OOleIIIII~CO.OOOleIllIIIITo.eoc4IIIII>>ITOAOOlellllllel tiOOCI)IIIIIelTt.eotlelNWI)IIIINMNIICIN.TCNI0IION.TC4IItII~IN.T$4IICIIWlN.'IQeIltl(NI=N.TONIICllelN.TONIICI leoIN.TC4IICIleeNW

~O.TONIItlIeellICIN.TCNIltllel oTNC1covl1t<<ICNTootIoct1$:lc<<eeo<<eeaoeaoo)o>>Ia>>ooe)I0IT%7141TC.1141OTlet1li)o)OVleAAeoeee~<<o>>e<<tSTe)L<<ACl<<sLICtNCCCCONTACT)OATillLt1Iltl>>A<<etWesleyH.BackusTechnical Assistant totheOperations ManagerAIIOACOOlTILC)leONC NVQOCA31524-4446COeetLCTC ONCLINC)01CAC>>lCO<<e)ONCNT

)AILUACOtlC1IOCO INTNICAtt01TlltlcAvlcCYOTC<<ecoco)oNCNT e)ANvtAcTVACActoATACLC

.+:"ke~~+pju>>.~'TOIe)AOC>>Aj~Yn~k,ee>>'~Qg, CAVltCYOTCIIs'>>>>>>'ehv+v;o>>>>~(e>>Q+PP+c~p, COee)ONCNT>>ANVtAC,TUACACV)YLC4CNTAL AttOATCA)CCTCOIlel'YCCIIItee,e<<ee<<e>>CA)CCTCOCV)<<IICCION CATO)XNO<<ACTAAcTIL<<evls1)00eoas,Ieeooeoeeev>>I)

III>>oee<<etvvoeee Itoeeee>>I>>o

<<esl114t1)CCTCOwo<<elttloN OATCIlllIIONT>>eCAYYCANOnJune29,1991at1754ESTwiththereactoratapproximately 98%fullpower,the"A"Emergency DieselGenerator startedautomatically duetoanapparentundervoltage signalfromtheBus14Undervoltage Monitoring System.The"A"Emergency DieselGenerator, afterstarting, attainedpropervoltageandfrequency.

Bydesign,itdidnotcloseintoBus14becauseBus14wasatitspropervoltageandbeingfedfromitsnormalpowersupply.Immediate operatoractionwastoverifythatBus14wasenergized andthatthe"A"Emergency DieselGenerator wasoperating normally.

Subsequently) the"A"Emergency DieselGenerator wasstoppedandrealigned forauto-standby.

Thecauseoftheeventhas.notbeenpositively determined, althoughoff-siteelectrical disturbance ispostulated.

Sincethecauseofthiseventhasnotbeenpositively determined atthistime,wewillcontinuetoinvestigate fortheunderlying cause.Anyfurthercorrective actionwilldependonthere'suitsofthisinvestigation.

eeACtoesONIOACI

~0~0

~e~H(ICFMmdddA(045)L'ICENSEE EVENTREPORTILERITEXTCONTINUATION 3U.d.HUCLCA(IHKOULATOHY COMM(dd(OH AFFHOVEOOMdHO5150M(04dkF(Added(5((55 FACILITYHAMd(IIR.E.GinnaNuclearPowerPlantTEXTIN'cccMcccHmdvckd.vccNMcckncc(

4(NCFckmJ(d(4'cl((T(OOC((ETHUMddll(1(0s00024491Ld(IHUMddll(dl5~OVCHZIAL4HVMk-006kdVMIOHHUM0FAOd(5102DFO6PRE-EVE2iT PLANTCONDITIONS Theplantwasatapproximately 984steadystatefullpowerwithno'ajoractivities inprogress.

II.DESCRIPTION OF%TENTA.DATESANDAPPROXIMATE TIMESOPMAJOROCCURRENCES:

000June29,1991,1754EDST:EventDateandTimehJune29,1991,1754EDST:Discovery DateandTimeJune29,1991,2013EDST:"A"Emergency DieselGenerator stoppedandrealigned forAuto-standby B.EVENT:OnJune29,1991at1754EDST,withthereactoratapproximately 98%fullpower,theControlRoomreceivedthefollowing alarms:L-14(Bus14.Undervoltage

-Safeguards) andJ-24(Emergency DieselGen1APanel).TheControlRoomoperators immediately verifiedpropervoltageonBus14andthatthenormalpowersupplybreakerwasclosed.TheControlRoomoperators alsoverifiedthatthe"A"Emergency DieselGenerator hadstartedanddisplayed propervoltageandfrequency.

Bydesign,the"A"Emergency DieselGenerator didnotcloseintoBus,14,asthebusvoltagewasnormalandBus14wasstillbeingsuppliedbyitsnormalpowersupply.HACFOAM544*(Iddl

~0

~0~eNRCSotw295A(042IL'ICENSEE EVENTREPORTILERITEXTCONTINUATION U.S.NUCLEARREQVLATORY COMMI55ION ASSROVEOOM9NOSISOWI04JEXSIRES,9121/99SACILITYNAME111OOCKETNVMEER121LERNVMQEII19155QUENTIAL NUMREVISIONNUMSAOEl21R.E.GinnaNuclearPowerPlantTEXTIIJ~<<>>5~N~.v>>NAS55JNJHRCFOnn2OEA'5IIITIo5ooo244,0060003pF06Subsequently, Auxiliary operators weredispatched tochecktheBus14Undervoltage Monitoring Systemcabinetsandtheoperation ofthe"A"Emergency DieselGenerator.

Theoperation ofthe"A"Emergency DieselGenerator wasfoundtobenormal.Noundervoltage triptargetswereobservedonBus14orBus18(boththesebusesarefedbythe"A"Emergency

.DieselGenerator).

Duringthisevent,routineactivities wereoccurring atoff-siteStation204.Atapproximately thesametimeastheapparentundervoltage condition occurredonBus14,a34.5kvcapacitor bankwasbeingremovedfromservice.Thisisaroutineactiontocorrectoff-sitevoltagesituations.

Station204'eedsCircuit751,whichwasthenormaloff-sitepowersupplytoBuses14and18.Control=Roomoperators notifiedhighersupervision andtheNuclearRegulatory Commission oftheevent.Toproveoperability oftheUndervoltage Monitoring System,theResultsandTest(R&T)Department performed PeriodicTestprocedure PT-9.1(Undervoltage Protection 480VoltSafeguards Busses)onBus14.AfterPT-9.1.wassuccessfully completed, the"A"Emergency DieselGenerator wasstoppedandrealigned forAuto-standby.

C.INOPERABLE STRUC'HIRES, COMPONENTS sORSYSTEMSTHATCONTRIBUTED TOTHEEVENT:None.D.OTEGsRSYSTEMSORSECONDARY PUNCTIONS AFFECTED:

E.None.METHODOPDISCOVERY:

Theeventswereimmediately apparentduetoalarmsandindications intheControlRoom.NRCSORM255AI94ll

.OO

<<ACSottoSSSA~eL'ICENSEE EVENTREPORT(LER)TEXTCONTINUATION V,S.<<UCLEAIIIlfOULATOIIY COMMISSIOII ASSAOYEOOMSHO3150MIOIIEXSIAES,SISIl95SACILITYNAMEIllR.E.GinnaNuclearPowerPlantTEXTillnave<<WCe<<nquseCvASOdakevWlYPCArm~'llIITIOOCKETIIUMSEII11Iosooo24LEII<<UMSEIIISI5~4UC<<VIAL'SV<<IONHUM<<'"<<UMf<<9-1-006-00~AOSISI04o~06F.OPERATORACTXON:Following theBus14Undervoltage Alarmandthe"A"Emergency DieselGenerator automatic start,theCo'ntrolRoomoperators immediately verifiedpropervoltageonBus14viathenormalpowersupplyand',thatthe"A"Emergency DieselGenerator displayed propervoltageandfrequency.

Subsequently, Auxiliary operators weredis'patched tocheck-theBus14undervoltage monitoring systemand"A"Emergency DieselGenerator operation.

The"A"Emergency DieselGenerator operation wasnormaland,noundervoltage triptargetswereobservedonBus14orBus18.'t"The"A"Emergency DieselGenerator wassubsequently stoppedandrealigned forAuto-standby.

G.SAFETXSXSTEMRESPONSES:

The"A"Emergency DieselGenerator automatically startedanddisplayed propervoltageandfrequency.

'IXI.CAUSEOFEV19Fl'.XMM1sDIATE CAUSE:Theautomatic actuation ofthe-"A"Emergency DieselGenerator wasduetoanapparentundervoltage signalfromtheBus14undervoltage monitoring system.B.ROOTCAUSE:Theunderlying, causeoftheapparentundervoltage signalfromtheBus14undervoltage monitoring systemisnotpositively determined atthistime..MACSO<<MSSSAI941l

~0 IIACSovvvv444A14451~eoeL'ICENSEE EVENTREPORT(LERITEXTCONTINUATION U,E.NUCLEAAAEOULATOAY COMMIEEIOII

/ASSAOVEOOMEIVO1150MIOeEXSIAES,4151/45SACILITYIIAMEIllR.E.GinnaNuclearPawerPlantTExTlllnaveMeceaeevveevLvvMvneeevalvYACSevvnSELAYlIITICOCKETIvUMEEA111osooo244vEAALEIIIIUMEEA14154004VVTIAL~VUM006ntvlelOMVVVM00SAOEIEI050F06IV.ANALYSISOFEVENTTheeventisreportable inaccordance with10CFR50.73,LicenseeEventReportSystem,item(a)(2)(iv),

whichrequires'eporting of,"anyeventorcondition thatresultedinmanualorautomatic actuation ofanyEngineered SafetyFeature(ESF)including theReactor.Protection System(RPS)".Thestartingofthe"A"Emergency DieselGenerator wasanautomatic actuation ofanESFsystem.Anassessment wasperformed considering boththesafetyconsequences andimplications ofthiseventwiththefollowing resultsandconclusions:

Therewerenooperational orsafetyconsequences orimplications attributed tothestartingofthe"A"Emergency DieselGenerator because:0The"A"Emergency DieselGenerator operatedasdesigned.

oBothBus14powersupplies(i.e.normalandemergency) wereeitherinuseoravailable throughout theevent.oTheBus14undervoltage monitoring systemoperation wasintheconservative direction, (i.e.theoperation actuatedtheautomatic startofthe"A"Emergency DieselGenerator).

Basedontheabove,itcanbeconcluded thatthepublic'shealthandsafetywasassuredatalltimes.V.CORRECTIVE ACTIONA.ACTIONTAKENTORETURNAFFECTEDSYSTEMSTOPRE-EVENT NORMALSTATUS:oTheR&TDepartment successfully completed PT-9.1onBus14andthe"A"Emergency DieselGenerator wasstoppedandalignedforAuto-standby.

~VACS0VIM544A14411

~1~0 NAC>armSEEAIHEI~0I.'ICENSEE EVENTREPORT(I.ER)TEXTCONTINUATION V.S.NVCLEAIIIIEOVLATOIIY COMMISSION IAtfAOVEOOMEHO$1$0MIOIE)CrllIES.

EISI4$FACILITYNAMEIIIOOCIIETNVMEEIIIEIYEAALEIINVMEEIIIEIIEQVEHTIAL 4MIAAEVISIO<NVMIA~ACEISIR.E.GinnaNuclearPowerPlantTEILillmortapeceemewaf.wtaAkenVHACFiwnDELI'IlIITlosooo.244910060006'F06B.ACTXONTAKENORPLANNEDTOPREVENTRECURRENCE:

000Astheunderlying causeoftheeventhasnotbeendetermined atthistime,investigations willcontinuetopositively determine theunderlying causeofthisevent.Anyfurthercorrective actionswilldependontheresultsoftheseinvestigations.

Electrical systemmonitoring recordshavebeenreviewed, andindicatethatremovalofthecapacitor bankresultedinasmallandroutinevoltagetransient.

Electrical systemmonitoring hasbeenincreased onCircuit751.0Theinterface betweentheundervoltage monitoring systemanddieselstartcircuitry willcontinuetobeevaluated,'to determine iftheundervoltage systemisreactingasdesignedforsmallvoltagefluctuations.

ADDXTXONAL XNFORMATION A.B.PAXLEDCOMPONENTS:

None.PREVXOUSLERsONSIMILAREVENTS:AsimilarLEReventhistorical searchwasconducted withthefollowing results:Nodocumentation ofsimilarLEReventswithanundetermined rootcauseatGinnaStationcouldbeidentified.

C.SPECIALCOMMENTSNone.%ACSOIIMSEEAISAl

~01~f