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{{#Wiki_filter:REGULATORYINFORMATIONDISTRIBUTIONSYSTEM(BIDS>DISTRIBUTIONFORINCOMINGMATERIAL50-387REC:GRIER8HNRCORG:CURTISNWPAPNR5LIGI-lTDOCDATE:09/15/78DATERCVD:09/22/78DOCTYPE:LETTERNOTARIZED:NOCOPIESRECEIVED
{{#Wiki_filter:REGULATORY INFORMATION DISTRIBUTION SYSTEM(BIDS>DISTRIBUTION FORINCOMINGMATERIAL50-387REC:GRIER8HNRCORG:CURTISNWPAPNR5LIGI-lTDOCDATE:09/15/78DATERCVD:09/22/78DOCTYPE:LETTERNOTARIZED:
NOCOPIESRECEIVED


==SUBJECT:==
==SUBJECT:==
LTR1ENCLFURNISHINGSUPPLEMENTTOAPPLICANT"SLTRSOF04/17/73AND07/14/78CONTAININGFINALCONSTRUCTIONDEFICIENCYREPTCONCERNINGDEFICIENCYINEISMICQUALIFICATIONOFMEDIUMVOLTAGEM.TALCLADSAFEGUARDSWITCHGEAR.PLANTNAME:SUSQUEHANNA"<<UNIT1uv%%%%%%%%%%%%%%%DISTRIBUTIONOFTHISMATERIALNOTES:SENDIS(E3CYSFSAR8(ALLAMDTGCONSTRUCTIONDEFICIENCYREPORT<10CFR50.55E)(DISTRIBUTIONCODE8019>REVIEWERINITIAL:XJMDISTRIBUT0BINITIAL~IGASFOLLOWS%%<%%%%%%%%%%%%%%%FORACTION:INTERNAL:EXTERNAL:ASSTDIRVASSALL0%%W/ENCLPRMINER%%W/ENCL.6FILE%%/ENCL0ENCL,GOScSICKRcSTAFF%%W/ENCLDIRECTORDPM%%W/ENCLQAB%%W/ENCLADFORENG%kW/ENCLADFORPLANTSYSTEMS%%W/ENCLSTANDARDSDEV.%%W/ENCLFERDDREHER/IE%%W/ENCLLPDRSNILKESBARREiPA%%M/ENCLTERA<<%W/ENCLNSIC%%W/ENCLACRSCATB%%W/16ENCLBRCI.IIEFLWR03BC%%W/ENCLLICASSTLWR83LA<<W/ENCLNRCPDR%%W/ENCLOELDu~W/ENCLMIPC%%W/ENCLDEPUTYDIRDPM%%W/ENCLDIRECTORDSS%%W/ENCLADFORREACSFTY%%W/ENCLADFORSYS8(PROJ%%W/ENCLKSEYFRIT/IE%%W/ENCLCONTROLNBR:780860147At~THEEND  
LTR1ENCLFURNISHING SUPPLEMENT TOAPPLICANT"S LTRSOF04/17/73AND07/14/78CONTAINING FINALCONSTRUCTION DEFICIENCY REPTCONCERNING DEFICIENCY INEISMICQUALIFICATION OFMEDIUMVOLTAGEM.TALCLADSAFEGUARDS WITCHGEAR.
PLANTNAME:SUSQUEHANNA
"<<UNIT1uv%%%%%%%%%%%%%%%
DISTRIBUTION OFTHISMATERIALNOTES:SENDIS(E3CYSFSAR8(ALLAMDTGCONSTRUCTION DEFICIENCY REPORT<10CFR50.
55E)(DISTRIBUTION CODE8019>REVIEWERINITIAL:XJMDISTRIBUT0B INITIAL~IGASFOLLOWS%%<%%%%%%%%%%%%%%%
FORACTION:INTERNAL:
EXTERNAL:
ASSTDIRVASSALL0%%W/ENCL PRMINER%%W/ENCL
.6FILE%%/ENCL0ENCL,GOScSICKRcSTAFF%%W/ENCL DIRECTORDPM%%W/ENCL QAB%%W/ENCL ADFORENG%kW/ENCL ADFORPLANTSYSTEMS%%W/ENCL STANDARDS DEV.%%W/ENCLFERDDREHER/IE%%W/ENCL LPDRSNILKESBARREiPA%%M/ENCL TERA<<%W/ENCL NSIC%%W/ENCL ACRSCATB%%W/16ENCLBRCI.IIEFLWR03BC%%W/ENCL LICASSTLWR83LA<<W/ENCL NRCPDR%%W/ENCL OELDu~W/ENCL MIPC%%W/ENCL DEPUTYDIRDPM%%W/ENCL DIRECTORDSS%%W/ENCL ADFORREACSFTY%%W/ENCL ADFORSYS8(PROJ%%W/ENCL KSEYFRIT/IE%%W/ENCL CONTROLNBR:780860147 At~THEEND  
~'I  
~'I  
~g~"~~;-),$)I)~~.(gPg~XKDsesTWONORTHNINTHSTREET,ALLENTOWN,PA.18101/g$ITJNE:(215)821-5151NORMANW,CURTISVicePresidentEngineering8Construction821-5381SeptEmber15,1978Mr.BoyceH.GrierDirector,RegionIU.S.NuclearRegulatoryCczanission631ParkAvenueKingofPrussia,Pennsylvania17406CJo>Irrc's'nv>+mCnrnCllPl<onaP1~CDC)SUSQUEEQKASTEAMELECTRICSTATIONF3'EPORTOFADEFICIENT',CYINSEISMICQUAIZFICATIONOFI%DENVOLTAGE,M'TALCLAD,SM."%GUARDSSWITCHGFARDOCKETNO.:50-387LICENSENO:CPPR-101ER100450FILE840-4PLA289'~=I~4\I
~g~"~~;-),$)I)~~.(gPg~XKDsesTWONORTHNINTHSTREET,ALLENTOWN, PA.18101/g$ITJNE:(215)821-5151NORMANW,CURTISVicePresident Engineering 8Construction 821-5381SeptEmber 15,1978Mr.BoyceH.GrierDirector, RegionIU.S.NuclearRegulatory Cczanission 631ParkAvenueKingofPrussia,Pennsylvania 17406CJo>Irrc's'nv>+mCnrnCllPl<onaP1~CDC)SUSQUEEQKA STEAMELECTRICSTATIONF3'EPORTOFADEFICIENT',CY INSEISMICQUAIZFICATION OFI%DENVOLTAGE,M'TALCLAD,SM."%GUARDS SWITCHGFAR DOCKETNO.:50-387LICENSENO:CPPR-101ER100450FILE840-4PLA289'~=I~4\I


==DearMr.Grier:==
==DearMr.Grier:==
ThissupplementsPPSZlettersPLA-246,datedApril17,1978andPLA-271,datedJuly14,1978,andprovidesafinalreportofthesubjectdeficiencyasrecpuzedby10CFR50.55(e).Pleaseadviseshouldyourecureadditionalinformation.Verytrulyyours,N.W.CurtisVicePresident-Engineering6ConstructionAttachmentARS:mcbcc:Mr.J.G.Davis(15)ActingDirector-OfficeofInspection6EnforcementU.S.NuclearReyQatoryCcmiission--Washington,D.C.20555Mr.G.MDonald,Director(1)OfficeofManaganent,,Information6~amContxol'U.S.NuclearRegulatoryCcmtissionWashington,D.C.20555PENNSYLVANIAPOWER8,LIGHTCOMPANYt78p86p1479'e~t  
Thissupplements PPSZlettersPLA-246,datedApril17,1978andPLA-271,datedJuly14,1978,andprovidesafinalreportofthesubjectdeficiency asrecpuzedby10CFR50.55 (e).Pleaseadviseshouldyourecureadditional information.
'Mr.B.H.GrierSept.anber15,1978cc:Mr.RobertM.GalloU.S.NuclearRegulatoryGmxnissionP.O.Box52Shickshinny,Pennsylvania18655 OFADEFICIENCYINSEISMICQUALIFICATIONOFMEDIUMVOLTAGE,MEALCLAD,SAFEGUABDSSWHCHG1RRFORTHESUSQUEHANNASTEAM1KZCTRICSTATICND.P.ParsonsSSESElectricalGroupSupvr.ApprovedBy:..~~~9r~pg.A.M.eSupervisingEngineer-Design-SuscpehannaReviewed:A.R.ScilManager-NuclearQualityAssurancePENNSYLVANIAHMK6LIGHTCCMPANYAL'EZKTQWN,PENNSYLVANIAS1M.'EMBER15,1978 TABLEOFCONTENTSIntroductionDescriptionofDeficiencyAnalysisofSafetyImplicationsCorrectiveActionConclusionPg.lPgs,lg2g3Pg.3Pgs.4,5Pg.5 INTRODUCZIONThisreportispreparedinaccordancewiththerequirementsdescribedinTitle10,CodeofFederalRegulations,Part50,Section50.55(e).PPKwasadvised,throughitsA/E(Bechtel)organization,t1wtWestinghousesupplied,mediumvoltage,metalcladswitchgearwasnotcapableofwithstandingthepostulatedseismiceventforSusquehannaPlant.BechtelwasrequestedtoreviewthesituationandadvisePPsZofitsfindings.OnParch31,1978theNRCwasinformedthatadeficiency,potentiallyreportableunder10CFR50.55(e),wasbeingevaluated,andonApril17,1978,followinganengineeringreview,PALissueditsInterimReportofthedeficiency.Thedeficiencywasdeterminedtobereportableunder10CFR50.55(e)forthefollowingreasons:1.Thedeficiency,wereittoremainuncorrected,couldhaveresultedinasafetyhazardtotheoperationoftheplant.2.Thedeficiencyrepresentedadeficiencyinfinaldesignasapprovedandreleasedforfabricationandinstallation.3.Eightsafety-relatedswitchgearunitshad,beenshippedandacceptedforinstallationbeforethedeficiencywasdiscovered.DJHCRIPTIONOFDEFICIENCYTheSusquehannaPlantwassuppliedeightdeficientsafetyrelatedmediumvoltageswitchgearunitsbyWestinghouse.Fouroftheseswitchgearunitssupplypowerdirectlyto4kvsafetyrelatedequipnent,pumprmtorsandloadcenters,>RichareusedtomitigatetheeffectsofanaccidentinUnitl.
Verytrulyyours,N.W.CurtisVicePresident-Engineering 6Construction Attachment ARS:mcbcc:Mr.J.G.Davis(15)ActingDirector-Office ofInspection 6Enforcement U.S.NuclearReyQatory Ccmiission--
Likewise,fourswitchgearunitsareusedasthesupplyfor4kvsafetyrelatedloadsonUnit2.Eachswitchgearunit,containsthreepotentialtransformercircuits,oneofthecircuitsconsistsof~potentialtransformersconnectedinanopendelta.Theothertwocircuitseachcontainonepotentialtransformerusedtosensesinglephasepotential.Thepotentialtransformersareusedtoobtain120volt,potentialirr3icationforusewithrelaysontheswitchgearunits'heIIediumVoltageYwtalCladSwitchgear(Safeguards)Specification(8856-E-109)requirestheequipmenttomeetseismicrecpdxementsofProjectSpecification8856-6-10,IEEEStandardM.344,andtoreaeinfunctional,koth,duringandafteranOBEorDBE.WestinghouseadvisedBechtelonJanuary24,1978thatthepotentialtransformersecondarydisconnectingcontactassanbliesonequignentsimilartothatsuppliedforSusquehannahadfailedtowithstandrecentseismictests.Westinghousefurtherstatedthat,underseismicconditions,itispossiblethattheslip-fitsecondarycontactscouldbedislodgedfrantheirnormalpositionsresultinginopenor.shortcircuitingofthesecondarycircuits.WestinghouserequestedthatBechtelevaluatetheconditiontodetaanineifitauldconstituteasafetyhazard..Westinghouseconfirmedthattherewerenofailuresofpotentialtransformercircuitsduringtheoriginalseismicqualificationtests.However,thesecircuitsweresubsequent1yredesignedandthenewdesignwasanalyticallyqualified.Situalseismictestsonswitchgearunitsincorporatingthenewdesignresultedinthepotentialtransformercircuitfailures>M.charethesubjectofthisreport.
Washington, D.C.20555Mr.G.MDonald,Director(1)OfficeofManaganent,,Information 6~amContxol'U.S.NuclearRegulatory Ccmtission Washington, D.C.20555PENNSYLVANIA POWER8,LIGHTCOMPANYt78p86p147 9'e~t  
Westinghousealsoconfirmedthattheseianicqualificationofallothercanponentsintheseassembliesremainvalid.MALYSISOFSMOKYIMPLICATIONSTheengineeringevaluationdeterminedthattheopenorshortcircuitingofanyoftheseco~contactscouldresult.inincorrectoperationofaswitchgearunit.Itwasconcludedthattheworstconditionresultsfranthelossofallthreepotentialtransformercircuitsoneachswitchgearbus.Underthiscondition,thetminccmingbusfeedersfrcmthesafeguardtransformers(onefromeachoffsitesource)wouldbeautomaticallydisconnectedfrcmeachswitchgearbusandthedieselgeneratorpowersourceconnectedrestoringpowertothebus.ALOCAoccuringduringorafterthepostulated,seismiceventwouldinitiateaclosingsignaltothemotorfeederbreakersoftheshutdownloads,i.e.RHRandCoreSprayHotors.ThesefeederbreakerswouldcloseandismMiatelytripduetothefalseundervoltageindicationassensedbytheundervoltagerelay.Thecircuitbreakerswouldbeunabletocloseagainbecauseofthepermanentundervoltagetripsignalimposedonthem.Theaboveanalysisassumes'hat,thefailuresconcurrentlyoccuronallredundantm~tchgearhuses.BasedupontheevaluationofBechtelEngineering~itisconcludedthatthisconditionofnotbeingabletosupplypowertotheshutdownloadsunderaDXKconditionconstitutesasafetyhazardtotheoperationoftheplantandrepresentsadeficiencyinfinaldesign.  
'Mr.B.H.GrierSept.anber 15,1978cc:Mr.RobertM.GalloU.S.NuclearRegulatory Gmxnission P.O.Box52Shickshinny, Pennsylvania 18655 OFADEFICIENCY INSEISMICQUALIFICATION OFMEDIUMVOLTAGE,MEALCLAD,SAFEGUABDS SWHCHG1RR FORTHESUSQUEHANNA STEAM1KZCTRICSTATICND.P.ParsonsSSESElectrical GroupSupvr.ApprovedBy:..~~~9r~pg.A.M.eSupervising Engineer-Design-Suscpehanna Reviewed:
A.R.ScilManager-Nuclear QualityAssurance PENNSYLVANIA HMK6LIGHTCCMPANYAL'EZKTQWN, PENNSYLVANIA S1M.'EMBER 15,1978 TABLEOFCONTENTSIntroduction Description ofDeficiency AnalysisofSafetyImplications Corrective ActionConclusion Pg.lPgs,lg2g3Pg.3Pgs.4,5Pg.5 INTRODUCZION Thisreportispreparedinaccordance withtherequirements described inTitle10,CodeofFederalRegulations, Part50,Section50.55(e).PPKwasadvised,throughitsA/E(Bechtel) organization, t1wtWestinghouse
: supplied, mediumvoltage,metalcladswitchgear wasnotcapableofwithstanding thepostulated seismiceventforSusquehanna Plant.Bechtelwasrequested toreviewthesituation andadvisePPsZofitsfindings.
OnParch31,1978theNRCwasinformedthatadeficiency, potentially reportable under10CFR50.55(e),
wasbeingevaluated, andonApril17,1978,following anengineering review,PALissueditsInterimReportofthedeficiency.
Thedeficiency wasdetermined tobereportable under10CFR50.55(e) forthefollowing reasons:1.Thedeficiency, wereittoremainuncorrected, couldhaveresultedinasafetyhazardtotheoperation oftheplant.2.Thedeficiency represented adeficiency infinaldesignasapprovedandreleasedforfabrication andinstallation.
3.Eightsafety-related switchgear unitshad,beenshippedandacceptedforinstallation beforethedeficiency wasdiscovered.
DJHCRIPTION OFDEFICIENCY TheSusquehanna Plantwassuppliedeightdeficient safetyrelatedmediumvoltageswitchgear unitsbyWestinghouse.
Fouroftheseswitchgear unitssupplypowerdirectlyto4kvsafetyrelatedequipnent, pumprmtorsandloadcenters,>RichareusedtomitigatetheeffectsofanaccidentinUnitl.  
: Likewise, fourswitchgear unitsareusedasthesupplyfor4kvsafetyrelatedloadsonUnit2.Eachswitchgear unit,containsthreepotential transformer
: circuits, oneofthecircuitsconsistsof~potential transformers connected inanopendelta.Theothertwocircuitseachcontainonepotential transformer usedtosensesinglephasepotential.
Thepotential transformers areusedtoobtain120volt,potential irr3ication forusewithrelaysontheswitchgear units'heIIediumVoltageYwtalCladSwitchgear (Safeguards)
Specification(8856-E-109) requirestheequipment tomeetseismicrecpdxements ofProjectSpecification 8856-6-10, IEEEStandardM.344,andtoreaeinfunctional, koth,duringandafteranOBEorDBE.Westinghouse advisedBechtelonJanuary24,1978thatthepotential transformer secondary disconnecting contactassanblies onequignent similartothatsuppliedforSusquehanna hadfailedtowithstand recentseismictests.Westinghouse furtherstatedthat,underseismicconditions, itispossiblethattheslip-fitsecondary contactscouldbedislodged frantheirnormalpositions resulting inopenor.shortcircuiting ofthesecondary circuits.
Westinghouse requested thatBechtelevaluatethecondition todetaanine ifitauldconstitute asafetyhazard..Westinghouse confirmed thattherewerenofailuresofpotential transformer circuitsduringtheoriginalseismicqualification tests.However,thesecircuitsweresubsequent1y redesigned andthenewdesignwasanalytically qualified.
Situalseismictestsonswitchgear unitsincorporating thenewdesignresultedinthepotential transformer circuitfailures>M.charethesubjectofthisreport.
Westinghouse alsoconfirmed thattheseianicqualification ofallothercanponents intheseassemblies remainvalid.MALYSISOFSMOKYIMPLICATIONS Theengineering evaluation determined thattheopenorshortcircuiting ofanyoftheseco~contactscouldresult.inincorrect operation ofaswitchgear unit.Itwasconcluded thattheworstcondition resultsfranthelossofallthreepotential transformer circuitsoneachswitchgear bus.Underthiscondition, thetminccmingbusfeedersfrcmthesafeguard transformers (onefromeachoffsitesource)wouldbeautomatically disconnected frcmeachswitchgear busandthedieselgenerator powersourceconnected restoring powertothebus.ALOCAoccuringduringorafterthepostulated, seismiceventwouldinitiateaclosingsignaltothemotorfeederbreakersoftheshutdownloads,i.e.RHRandCoreSprayHotors.ThesefeederbreakerswouldcloseandismMiately tripduetothefalseundervoltage indication assensedbytheundervoltage relay.Thecircuitbreakerswouldbeunabletocloseagainbecauseofthepermanent undervoltage tripsignalimposedonthem.Theaboveanalysisassumes'hat, thefailuresconcurrently occuronallredundant m~tchgear huses.Basedupontheevaluation ofBechtelEngineering~it isconcluded thatthiscondition ofnotbeingabletosupplypowertotheshutdownloadsunderaDXKcondition constitutes asafetyhazardtotheoperation oftheplantandrepresents adeficiency infinaldesign.  
,IP,t,,~
,IP,t,,~
CORRECTIVE'ACTIONActionTakentoContxol'Deficient.'ItemsTheactionstakenbyBechtelpriortothesuhnittaloftheinterimreportofthedeficiencybyPP&LaredomunentedinPZA-246datedApril17,1978.Inadditiontothemeasurespreviouslyidentified,andintheinterestofobtainingdocumentedevidenceofBechtelPxojectEngineering'sevaluationofthecondition'scause,correctiveactionrequired,andreportabilityunder10CFR50.55(e),BechtelQAgeneratedIhnagerrentCorrectiveActionRequestNo.1-22datedMarch28,1978.CorrectiveActionto'Control'Resolution'of'theDeficienciesWestinghousehassuppliedmodificationkitswhichprovideforeliminatingthestationaxy,secondarydisconnectingcontactassembliesfromthepotentialtransformercircuits.Twenty-four(24)(threekitsforeachoftheeightsafety-relatedswitchgearunits)potentialtransfoxmersecondaryfieMrmdificationkits(WestinghouseStyleNo.628F14G01)havebeenprovided.TheserrodificationkitshavebeeninstalledbyBechtelfieldelectricianspertheinstructionsonWestinghousedrawing628F146.ThesechangesweremadeunderthesupervisionoftheWestinghouseEngineeringServicePersonnel.Themodificationconsistsofhardwiringthesecondaryarablecontacttoatexminalblockviaawiringharness.ThePTsecondarycircuitsarethenconnectedtothefieldsideoftheterminalblock.Thesecondarystationarycontactsareremovedentirely,thuseliminatingthesourceoftheseismicfailure.  
CORRECTIVE
~~I(~Westinghousehasseianicallyqualifiedthepotentialtransformerswiththe@edifiedsecondarycontactarrangement.DonznentedevidenceofthisqualificationhasbeenprovidedtoBechtelthrougharevisiontotheoriginalqualificationreport.COVZIJSXONSl4xlificationshavebeenmadetoaU.theWestinghousesafety-related,medianvoltageswitchgearunitscontainingpotentialtransformersandpurchasedunderP.O.8856-E-109ACforSusquehannaSteamElectricStation.TheBechtelgeneratedhMnconfoxmanceReport(NCRhM.2514)willnotbeclosedoutuntilBechtelQualityContxolhasperformedtheattendantinspectionsandhasverifiedthatthemxlificationkitsrareinstalledaccordingtodesignrequirements-Theandifiedswitchgearunitsarequalifiedtomeetthepostulatedseismicevent.forSusquehannaanddocumentationofthisseismicqualificationhasbeenreceivedandwillbereviewedbyBechtelEngineering.Bechtel'sacceptanceofthisdocumentationwillresultinanacceptablydocumentedrevisiontotheWestinghouseSeianicQualificationReport.Theswitchgearunits~aspresentlymodified,arecompatiblewithpurchaseorder,PSARandFSARrequiranents.}}
'ACTIONActionTakentoContxol'Deficient.'Items TheactionstakenbyBechtelpriortothesuhnittal oftheinterimreportofthedeficiency byPP&Laredomunented inPZA-246datedApril17,1978.Inadditiontothemeasurespreviously identified, andintheinterestofobtaining documented evidenceofBechtelPxojectEngineering's evaluation ofthecondition's cause,corrective actionrequired, andreportability under10CFR50.55(e),
BechtelQAgenerated Ihnagerrent Corrective ActionRequestNo.1-22datedMarch28,1978.Corrective Actionto'Control'Resolution
'of'theDeficiencies Westinghouse hassuppliedmodification kitswhichprovideforeliminating thestationaxy, secondary disconnecting contactassemblies fromthepotential transformer circuits.
Twenty-four (24)(threekitsforeachoftheeightsafety-related switchgear units)potential transfoxmer secondary fieMrmdification kits(Westinghouse StyleNo.628F14G01) havebeenprovided.
Theserrodification kitshavebeeninstalled byBechtelfieldelectricians pertheinstructions onWestinghouse drawing628F146.Thesechangesweremadeunderthesupervision oftheWestinghouse Engineering ServicePersonnel.
Themodification consistsofhardwiringthesecondary arablecontacttoatexminalblockviaawiringharness.ThePTsecondary circuitsarethenconnected tothefieldsideoftheterminalblock.Thesecondary stationary contactsareremovedentirely, thuseliminating thesourceoftheseismicfailure.  
~~I(~Westinghouse hasseianically qualified thepotential transformers withthe@edifiedsecondary contactarrangement.
Donznented evidenceofthisqualification hasbeenprovidedtoBechtelthrougharevisiontotheoriginalqualification report.COVZIJSXONS l4xlifications havebeenmadetoaU.theWestinghouse safety-related, medianvoltageswitchgear unitscontaining potential transformers andpurchased underP.O.8856-E-109AC forSusquehanna SteamElectricStation.TheBechtelgenerated hMnconfoxmance Report(NCRhM.2514)willnotbeclosedoutuntilBechtelQualityContxolhasperformed theattendant inspections andhasverifiedthatthemxlification kitsrareinstalled according todesignrequirements-Theandifiedswitchgear unitsarequalified tomeetthepostulated seismicevent.forSusquehanna anddocumentation ofthisseismicqualification hasbeenreceivedandwillbereviewedbyBechtelEngineering.
Bechtel's acceptance ofthisdocumentation willresultinanacceptably documented revisiontotheWestinghouse SeianicQualification Report.Theswitchgear units~aspresently
: modified, arecompatible withpurchaseorder,PSARandFSARrequiranents.}}

Revision as of 05:15, 29 June 2018

Susquehanna Units 1 and 2 - Letter Supplementing Pp&L Letters Dated April 17, 1978 and July 14, 1978 and Attaching a Final Report of a Deficiency in Seismic Qualification of Medium Voltage, Metal Clad, Safeguards Switchgear
ML18024A056
Person / Time
Site: Susquehanna  Talen Energy icon.png
Issue date: 09/15/1978
From: Curtis N W
Pennsylvania Power & Light Co
To: Grier B H
NRC Region 1
References
Download: ML18024A056 (12)
v • d • e


Text

REGULATORY INFORMATION DISTRIBUTION SYSTEM(BIDS>DISTRIBUTION FORINCOMINGMATERIAL50-387REC:GRIER8HNRCORG:CURTISNWPAPNR5LIGI-lTDOCDATE:09/15/78DATERCVD:09/22/78DOCTYPE:LETTERNOTARIZED:

NOCOPIESRECEIVED

SUBJECT:

LTR1ENCLFURNISHING SUPPLEMENT TOAPPLICANT"S LTRSOF04/17/73AND07/14/78CONTAINING FINALCONSTRUCTION DEFICIENCY REPTCONCERNING DEFICIENCY INEISMICQUALIFICATION OFMEDIUMVOLTAGEM.TALCLADSAFEGUARDS WITCHGEAR.

PLANTNAME:SUSQUEHANNA

"<<UNIT1uv%%%%%%%%%%%%%%%

DISTRIBUTION OFTHISMATERIALNOTES:SENDIS(E3CYSFSAR8(ALLAMDTGCONSTRUCTION DEFICIENCY REPORT<10CFR50.

55E)(DISTRIBUTION CODE8019>REVIEWERINITIAL:XJMDISTRIBUT0B INITIAL~IGASFOLLOWS%%<%%%%%%%%%%%%%%%

FORACTION:INTERNAL:

EXTERNAL:

ASSTDIRVASSALL0%%W/ENCL PRMINER%%W/ENCL

.6FILE%%/ENCL0ENCL,GOScSICKRcSTAFF%%W/ENCL DIRECTORDPM%%W/ENCL QAB%%W/ENCL ADFORENG%kW/ENCL ADFORPLANTSYSTEMS%%W/ENCL STANDARDS DEV.%%W/ENCLFERDDREHER/IE%%W/ENCL LPDRSNILKESBARREiPA%%M/ENCL TERA<<%W/ENCL NSIC%%W/ENCL ACRSCATB%%W/16ENCLBRCI.IIEFLWR03BC%%W/ENCL LICASSTLWR83LA<<W/ENCL NRCPDR%%W/ENCL OELDu~W/ENCL MIPC%%W/ENCL DEPUTYDIRDPM%%W/ENCL DIRECTORDSS%%W/ENCL ADFORREACSFTY%%W/ENCL ADFORSYS8(PROJ%%W/ENCL KSEYFRIT/IE%%W/ENCL CONTROLNBR:780860147 At~THEEND

~'I

~g~"~~;-),$)I)~~.(gPg~XKDsesTWONORTHNINTHSTREET,ALLENTOWN, PA.18101/g$ITJNE:(215)821-5151NORMANW,CURTISVicePresident Engineering 8Construction 821-5381SeptEmber 15,1978Mr.BoyceH.GrierDirector, RegionIU.S.NuclearRegulatory Cczanission 631ParkAvenueKingofPrussia,Pennsylvania 17406CJo>Irrc's'nv>+mCnrnCllPl<onaP1~CDC)SUSQUEEQKA STEAMELECTRICSTATIONF3'EPORTOFADEFICIENT',CY INSEISMICQUAIZFICATION OFI%DENVOLTAGE,M'TALCLAD,SM."%GUARDS SWITCHGFAR DOCKETNO.:50-387LICENSENO:CPPR-101ER100450FILE840-4PLA289'~=I~4\I

DearMr.Grier:

Thissupplements PPSZlettersPLA-246,datedApril17,1978andPLA-271,datedJuly14,1978,andprovidesafinalreportofthesubjectdeficiency asrecpuzedby10CFR50.55 (e).Pleaseadviseshouldyourecureadditional information.

Verytrulyyours,N.W.CurtisVicePresident-Engineering 6Construction Attachment ARS:mcbcc:Mr.J.G.Davis(15)ActingDirector-Office ofInspection 6Enforcement U.S.NuclearReyQatory Ccmiission--

Washington, D.C.20555Mr.G.MDonald,Director(1)OfficeofManaganent,,Information 6~amContxol'U.S.NuclearRegulatory Ccmtission Washington, D.C.20555PENNSYLVANIA POWER8,LIGHTCOMPANYt78p86p147 9'e~t

'Mr.B.H.GrierSept.anber 15,1978cc:Mr.RobertM.GalloU.S.NuclearRegulatory Gmxnission P.O.Box52Shickshinny, Pennsylvania 18655 OFADEFICIENCY INSEISMICQUALIFICATION OFMEDIUMVOLTAGE,MEALCLAD,SAFEGUABDS SWHCHG1RR FORTHESUSQUEHANNA STEAM1KZCTRICSTATICND.P.ParsonsSSESElectrical GroupSupvr.ApprovedBy:..~~~9r~pg.A.M.eSupervising Engineer-Design-Suscpehanna Reviewed:

A.R.ScilManager-Nuclear QualityAssurance PENNSYLVANIA HMK6LIGHTCCMPANYAL'EZKTQWN, PENNSYLVANIA S1M.'EMBER 15,1978 TABLEOFCONTENTSIntroduction Description ofDeficiency AnalysisofSafetyImplications Corrective ActionConclusion Pg.lPgs,lg2g3Pg.3Pgs.4,5Pg.5 INTRODUCZION Thisreportispreparedinaccordance withtherequirements described inTitle10,CodeofFederalRegulations, Part50,Section50.55(e).PPKwasadvised,throughitsA/E(Bechtel) organization, t1wtWestinghouse

supplied, mediumvoltage,metalcladswitchgear wasnotcapableofwithstanding thepostulated seismiceventforSusquehanna Plant.Bechtelwasrequested toreviewthesituation andadvisePPsZofitsfindings.

OnParch31,1978theNRCwasinformedthatadeficiency, potentially reportable under10CFR50.55(e),

wasbeingevaluated, andonApril17,1978,following anengineering review,PALissueditsInterimReportofthedeficiency.

Thedeficiency wasdetermined tobereportable under10CFR50.55(e) forthefollowing reasons:1.Thedeficiency, wereittoremainuncorrected, couldhaveresultedinasafetyhazardtotheoperation oftheplant.2.Thedeficiency represented adeficiency infinaldesignasapprovedandreleasedforfabrication andinstallation.

3.Eightsafety-related switchgear unitshad,beenshippedandacceptedforinstallation beforethedeficiency wasdiscovered.

DJHCRIPTION OFDEFICIENCY TheSusquehanna Plantwassuppliedeightdeficient safetyrelatedmediumvoltageswitchgear unitsbyWestinghouse.

Fouroftheseswitchgear unitssupplypowerdirectlyto4kvsafetyrelatedequipnent, pumprmtorsandloadcenters,>RichareusedtomitigatetheeffectsofanaccidentinUnitl.

Likewise, fourswitchgear unitsareusedasthesupplyfor4kvsafetyrelatedloadsonUnit2.Eachswitchgear unit,containsthreepotential transformer
circuits, oneofthecircuitsconsistsof~potential transformers connected inanopendelta.Theothertwocircuitseachcontainonepotential transformer usedtosensesinglephasepotential.

Thepotential transformers areusedtoobtain120volt,potential irr3ication forusewithrelaysontheswitchgear units'heIIediumVoltageYwtalCladSwitchgear (Safeguards)

Specification(8856-E-109) requirestheequipment tomeetseismicrecpdxements ofProjectSpecification 8856-6-10, IEEEStandardM.344,andtoreaeinfunctional, koth,duringandafteranOBEorDBE.Westinghouse advisedBechtelonJanuary24,1978thatthepotential transformer secondary disconnecting contactassanblies onequignent similartothatsuppliedforSusquehanna hadfailedtowithstand recentseismictests.Westinghouse furtherstatedthat,underseismicconditions, itispossiblethattheslip-fitsecondary contactscouldbedislodged frantheirnormalpositions resulting inopenor.shortcircuiting ofthesecondary circuits.

Westinghouse requested thatBechtelevaluatethecondition todetaanine ifitauldconstitute asafetyhazard..Westinghouse confirmed thattherewerenofailuresofpotential transformer circuitsduringtheoriginalseismicqualification tests.However,thesecircuitsweresubsequent1y redesigned andthenewdesignwasanalytically qualified.

Situalseismictestsonswitchgear unitsincorporating thenewdesignresultedinthepotential transformer circuitfailures>M.charethesubjectofthisreport.

Westinghouse alsoconfirmed thattheseianicqualification ofallothercanponents intheseassemblies remainvalid.MALYSISOFSMOKYIMPLICATIONS Theengineering evaluation determined thattheopenorshortcircuiting ofanyoftheseco~contactscouldresult.inincorrect operation ofaswitchgear unit.Itwasconcluded thattheworstcondition resultsfranthelossofallthreepotential transformer circuitsoneachswitchgear bus.Underthiscondition, thetminccmingbusfeedersfrcmthesafeguard transformers (onefromeachoffsitesource)wouldbeautomatically disconnected frcmeachswitchgear busandthedieselgenerator powersourceconnected restoring powertothebus.ALOCAoccuringduringorafterthepostulated, seismiceventwouldinitiateaclosingsignaltothemotorfeederbreakersoftheshutdownloads,i.e.RHRandCoreSprayHotors.ThesefeederbreakerswouldcloseandismMiately tripduetothefalseundervoltage indication assensedbytheundervoltage relay.Thecircuitbreakerswouldbeunabletocloseagainbecauseofthepermanent undervoltage tripsignalimposedonthem.Theaboveanalysisassumes'hat, thefailuresconcurrently occuronallredundant m~tchgear huses.Basedupontheevaluation ofBechtelEngineering~it isconcluded thatthiscondition ofnotbeingabletosupplypowertotheshutdownloadsunderaDXKcondition constitutes asafetyhazardtotheoperation oftheplantandrepresents adeficiency infinaldesign.

,IP,t,,~

CORRECTIVE

'ACTIONActionTakentoContxol'Deficient.'Items TheactionstakenbyBechtelpriortothesuhnittal oftheinterimreportofthedeficiency byPP&Laredomunented inPZA-246datedApril17,1978.Inadditiontothemeasurespreviously identified, andintheinterestofobtaining documented evidenceofBechtelPxojectEngineering's evaluation ofthecondition's cause,corrective actionrequired, andreportability under10CFR50.55(e),

BechtelQAgenerated Ihnagerrent Corrective ActionRequestNo.1-22datedMarch28,1978.Corrective Actionto'Control'Resolution

'of'theDeficiencies Westinghouse hassuppliedmodification kitswhichprovideforeliminating thestationaxy, secondary disconnecting contactassemblies fromthepotential transformer circuits.

Twenty-four (24)(threekitsforeachoftheeightsafety-related switchgear units)potential transfoxmer secondary fieMrmdification kits(Westinghouse StyleNo.628F14G01) havebeenprovided.

Theserrodification kitshavebeeninstalled byBechtelfieldelectricians pertheinstructions onWestinghouse drawing628F146.Thesechangesweremadeunderthesupervision oftheWestinghouse Engineering ServicePersonnel.

Themodification consistsofhardwiringthesecondary arablecontacttoatexminalblockviaawiringharness.ThePTsecondary circuitsarethenconnected tothefieldsideoftheterminalblock.Thesecondary stationary contactsareremovedentirely, thuseliminating thesourceoftheseismicfailure.

~~I(~Westinghouse hasseianically qualified thepotential transformers withthe@edifiedsecondary contactarrangement.

Donznented evidenceofthisqualification hasbeenprovidedtoBechtelthrougharevisiontotheoriginalqualification report.COVZIJSXONS l4xlifications havebeenmadetoaU.theWestinghouse safety-related, medianvoltageswitchgear unitscontaining potential transformers andpurchased underP.O.8856-E-109AC forSusquehanna SteamElectricStation.TheBechtelgenerated hMnconfoxmance Report(NCRhM.2514)willnotbeclosedoutuntilBechtelQualityContxolhasperformed theattendant inspections andhasverifiedthatthemxlification kitsrareinstalled according todesignrequirements-Theandifiedswitchgear unitsarequalified tomeetthepostulated seismicevent.forSusquehanna anddocumentation ofthisseismicqualification hasbeenreceivedandwillbereviewedbyBechtelEngineering.

Bechtel's acceptance ofthisdocumentation willresultinanacceptably documented revisiontotheWestinghouse SeianicQualification Report.Theswitchgear units~aspresently

modified, arecompatible withpurchaseorder,PSARandFSARrequiranents.
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