ML17213B133

Forwards Addl Info Re 821210 Degraded Grid Voltage Protection Submittals,Per 820223 Telcon.Voltage/Time Setpoints Will Be Supported by Two Undervoltage Devices

ML17213B133
Person / Time
Site:	Saint Lucie
Issue date:	03/11/1983
From:	UHRIG R E FLORIDA POWER & LIGHT CO.
To:	CLARK R A Office of Nuclear Reactor Regulation
References
L-83-139, NUDOCS 8303160200
Download: ML17213B133 (6)

Text

M+<<SAW<<H~~<<4LREGULAYINFORMATIONDISTRIBUTISYSTEM(BIDS)AOCESSIONNBRg8303160200DOCeDATE:83/03/11NOTARIZED:NOFACIL:50-335St.LuciePlant<UnitigFloridaPower&LightCo.AUTH~NAMEAUTHORAFFILIATIONUHRIGeReEe-FloridaPower8LightCo,-RECIPiNAMERECIPIENTAFFILIATION.CLARKgR,ADOperatingReactorsBranch3W

SUBJECT:

Forwardsaddiinfore821210degraded.grid.vol,tageprotectionsubmit.taisper820223telcon,Voltage/time.setpointswillbesupportedbytwo=undervoltagedevices.DISTRIBUTIONCODE:A015SiCOPIES'ECEIVED!LTR.ENCL,SIZE:,//TITLE!ORSubmittal;OnsiteEmergencyPower'"SystemNOTES'OCKET¹05000335RECIPIENTIDCODE/NAMENRRORB3BC01INTERNAL;NRR/DL/DRAB12-NRR/DSI/PSB14RGN2COPIESLTTRENCL771111.11RECIPIENTIDCODE/NAMEICSB09REGFI04AI/MIB18COPIFS'TTRENCL11EXTERNAL:ACRSLPDRNSI'C16'3056-61111INPOrJ~STARNESNRCPDR02NTIS1111)TOTALNUMBEROFCOPIESREQUIRED~LTTR24ENCL20 I'~'f4'"Kxqlgi<il,a<I$gNfI'hgpltxkvXK<<:,>7i~l.'l<~>a~'~~,>~r~~f)~t)rn"pqf~>i,l'3)~pf)hg,]g'))5.e,>9tv~rJ<~~~a'~v.ctaof<i])I'fgf-)l))i~)"gTqlf,g3<<)3~16'I>>,"IQ)00'1)t)6f>u909<$>>~pJ~>J1)'d'l)~~<lQ<<'q)(f>JQ]~zjqg$>j3)J'"A,'l,')l,)9'>i~~~~~ai~aipdthl50~a~l~~rlab~~>><>>ar~isa~~3:T34<.9J~.~~rtXv;y~sf~i).nvslvP65~>P~~~~vs~lr'PPt~~vo~~ok9v~fcas.,".~>Ivan>>~,Alfovzg>><<>OwlqI0aPa~c]qU..9uffr@4$~CQ)990e3hl~lI)>3~llTJ,g44I)l3)4Q5I'Ill)4-"ec,'fAh<<3'i<39)'l>If(ldg>)ldl)~~s~~y<~~we)yo~o,;~~@~3ofr,oA0fe4fl~1u~.~19:3JIIL;>3f,lil".97"kA3J)'43HYfJT.)3l'1I'33i)AJAX)'9(i)i)..IIt~~J)33i1)TJT~~.)Iqjtg.3.lq>A"%3J~10-)1f,gI,'5Ji(iIjjk~pp1l'(,g>a~lJIXk~.'9~'~>'~-.)IL3l)3I>cUl~~XU'~liAuhl~;icCil<IATi',l,q<>~fulll>l'lXx,lt)rt~~>~"~4JlX~~~II,J4.4r,l3l,PL,',.~3%J,<',,>y>Ji],~<qu)P)')JA:)All>)9'fxdillNJha$'JL tP.O.BOX14000,JUNOBEACH,FL3340BoQgFLORIDAPOWER&LIGHTCOMPANYMarch11,1983L-83-139OfficeofNuclearReactorRegulationAttention:Mr.RobertA.Clark,ChiefOperatingReactors8ranchg3DivisionofLicensingU.S.NuclearRegulatoryCommissionWashington,D.C.20555

DearMr.Clark:

Re:St.LucieUnit1DocketNo.50-335DegradedGridVoltageProtectionDuringatelephoneconferenceonFebruary23,1982withyourstaff,FloridaPower5Lightwasrequestedtoprovideadditionalinformationandclarifi-cationregardingourdegradedgridvoltagesubmittalsofDecember10,1982(L-82-536andL-82-537).Therequestedinformationisattached.Shouldyouoryourstaffhavefurtherqu'estionsonthissubject,pleasecontactus.VerytrulyyoursVicePresidentAdvancedSystemsIlTechnologyREU/PLP/jsAttachmentcc:J.P.O'Reilly,RegionIIHaroldF.Reis,EsquirePNS-LI-83-181-1r83031602008303iiPDRhDOCK05000335PPDRPEOPLE...SERVINGPEOPLE Glar'ificationstoFloridaPower&LightCompanylettersofDecember$0,1982(L-82-536andL-82-537),DegradedGridVoltageSt.LucieUnitIll.

Reference:

NRC-FloridaPower6LighttelephoneconferenceonFebruary23,1983.ClarificationNo.1:Describetheproposedundervoltagerelayinglogic-fixedtime,steps,fixedvoltage,numberofrelays,etc.ThefollowingdescribestheSt.LucieUnit//1proposedundervoltagerelayinglogicforboththe480voltand4160voltClassIEsafetyrelatedbusses.Oneachofthe480voltbussesthefollowingrelayinglogicisproposed.Presently,anITEtype27fixedvoltagefixedtimerelayisused.Thisrelay,contactisinserieswiththesafetyinjectionsignal,suchthatthisrelaycouldonlyactuateduringanaccidentcondition.Inordertosatisfythestaffrequirementandprecludeseparationfromtheoffsitesourceduetospuriousactuationofasinglerelayfollowingasafeguardsignal,asecondITEtype27willbeinstalled.Thetworelayswillbeparalleledandtheircontactswillbeseriesconnectedtoproducetherequiredacceptablecoincident2-out-of-2logicperbus.Eachofthe4160voltClassIEsafetyrelatedbusseswillhaveatotalofsix(6)undervoltagedevices..Thesewillbeofafixedtime,fixedvoltagetype.ThepresentWestinghouse'sCV-2--inversetimerelayswillnotbeutilized.AsproposedintheTechnicalSpecification,three(3)differentvoltage/timesetpointswillbeincorporatedin'theoverallrelayinglogicscheme.Eachsetofvoltage/timesetpointswillbesupportedbyasetoftwo(2)undervoltagedevices.Thisschememeetsthestaffrequirementforacoincident2-out-of-2logic.Ther'eisnointertiebetweentheAandB480voltClassIEbussesorbetween'heAandB4160voltClassIEbussesundervoltagetripping/dieselgeneratorstarting/loadsequencinglogics.Shouldtestingormaintenanceberequiredoradevicemalfunctionoccur,itwouldaffecttherespectivebusonly.TheotherbuswillremainconnectedtoitssourceandreadytoinitiateitsdieselgeneratorshoulditberequiredtoprovideprotectiveactionasspecifiedinIEEE-279-1971.The480voltand4160voltschemeswillinclude'builtintestabilityandannunicationofby-passinthecontrolroom.ClarificationNo.2:Whatistheequivalentvoltageonthe4KVbusthatcorrespondstothe429voltsconditiononthe480voltbus?Avoltageof429voltsonthe480voltClassIEsafetyrelatedbussescorrespondsto94.4%or3927voltsonthe4160voltClassIEbussesduringtheconditionwhentheunittripsFromfullloadandtransferstheloadstothestart-uptransformerwithaconcurrentaccidentcondition.Atthisvoltageonthe4160voltbusses,the4160voltequipmentiscapableofstartingandrunning.The429voltsetpointsatisfiesthestaffrequestthatthebusvoltageofallsafetyrelatedequipmentbeabovetheirrequiredstartingvoltageduringanaccidentcondition.

ClarificationNo.3:Clarifythe8seconds(7sec.+1sec)timedelayonthe480voltbusundervoltagerelays.Forthecaseoflossofoffsitepower,theperiodbetweenthetimeofanaccident(safetyinjectionactuationsignal-SIAS)andthetimewhenthesafetyinjectionsystemstartstopumpemergencycoolingwaterintothecoreisassumedtobe30secondsintheFSARaccidentanalyses.Thistimeincludesa10secondperiodinbringingthedieselgeneratoruptospeedandvoltage.The7seconds+1secondtimedelayforthe480voltundervoltagebusrelayscomesintoplayonlywhen'naccidentconcurrentwithadegradedsystemvoltageexists.SinceunderanSIASthedieselgeneratorautomaticallystarts,comesuptospeedandvoltagewithin10secondsandstandsbyreadytoacceptloads,the8secondsmaximumtimedelayinthe480voltrelaysdonotaddanyadditionaltimetothecorecoolinganlysisforaccidentconditionconcurrent.;withlossofoffsitepower.The8secondsmaximumtimeprecludesspuriousactuationduetomomentaryfluctua-tioninthesystemandthesystemisgivenanopportunitytoremainonthepreferredsource.ClarificationNo.4:Providedesigninformationsuchas,relaytypes,onelines,etc.,ontheproposedundervoltagerelayinglogicfor.the480voltand4160voltbusses.PDetaileddesignfortheproposedschemeonClarifications$through3abovearenotyetavailable.Thesedesignswillbefinalizedup'onacceptanceofourproposedrelayschemewiththeNRCstaff.TherequesteddetaileddesignscanbeforwardedtotheNRCstaffwhencomplete.ECrms