ML17223B393

Special Rept:On 911129,emergency Diesel Generator 1B Started for Weekly Operational Check & Output Voltage Climbed Above Nominal Voltage.Caused by Failed Component in Voltage Regulator Card.Regulator Card Replaced

ML17223B393
Person / Time
Site:	Saint Lucie
Issue date:	12/20/1991
From:	SAGER D A FLORIDA POWER & LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
L-91-346, NUDOCS 9201020058
Download: ML17223B393 (3)

Text

ACCELERATED DISTRIBREGULATORY INFORMATION DISTRIBUTION SYSTEM(RIDS)DOCKET05000335NOTES:ACCESSION NBR:9201020058 DOC.DATE:91/12/20NOTARIZED:

NOFACIL:50-335 St.LuciePlant,Unit1,FloridaPower&LightCo.AUTH.NAMEAUTHORAFFILIATION SAGER,D.A.

FloridaPower&LightCo.RECIP.NAME RECIPIENT AFFILIATION DocumentControlBranch"(Document Control'Desk)

SUBJECT:

Specialrept:on911129,emergency dieselgenerator 1Bstartedforweeklyoperational check&outputvoltagecl'imbedabovenominalvoltage.Causedbyfailedcomponent znvoltageregulator card.Regulator cardreplaced.

DISTRIBUTION CODE:IE22DCOPIESRECEIVED:LTR ENCLSIZE:TITLE:50.73/50.9 LicenseeEventReport(LER),IncidentRpt,etc.RECIPIENT IDCODE/NAME PD2-2LANORRIS,JINTERNAL:

ACNWAEOD/DOAAEOD/ROAB/DS PNRR/DET/EMEB 7ENRR/DLPQ/LPEB10 NRR/DREP/PRPB11 NRR/DST/SICB8H3 NRR/DST/SRXB 8ERES/DSIR/EIB EXTERNAL:

EG&GBRYCE,Z.H NRCPDRNSICPOOREIW~COPIESLTTRENCL1111221122111122111111331111RECIPIENT IDCODE/NAME PD2-2PDACRSAEOD/DSP/TPAB NRR/DET/ECMB 9HNRR/DLPQ/LHFB10 NRR/DOEA/OEAB NRR/DST/SELB 8DNRR/DSX/SQLBSDl RQG~FIGE~RG=-PIC01LSTLOBBYWARDNSICMURPHY,G.A NUDOCSFULLTXTCOPIESLTTRENCL11221111111111111111111111NOTETOALL"RIDS"RECIPIENTS:

PLEASEHELPUSTOREDUCEiVASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROO'klPl-37(EXT.20079)TOELlbIFNATEYOURNANCEFROMDISTRIBUTION LISTSFORDOCUAIENTS YOUDOiN'TNEED!TOTALNUMBEROFCOPIESREQUIRED:

LTTR33ENCL33 P.O.Box1.Pierce,FL34954-0128 December20,1991L-91-34610CFR50.36U.SNuclearRegulatory Commission Attn:DocumentControlDeskWashington, DC20555Gentlemen:

Re:St.LucieUnit1DocketNo.50-335SpecialReportDateofEvent:November29,1991EmerencDieselGenerator FailureTheattachedSpecialReportisbeingtransmitted pursuanttotherequirements ofSt.LucieUnit1Technical Specifications 4.8.1.2.2 and6.9.2..Thereportprovidesnotification ofa1BEmergency DieselGenerator failureduringtheweeklyoperational check.Shouldtherebeanyquestions onthisinformation, pleasecontactus~Verytrulyyours,D.A.VicePSt'geresidentiePlantDAS/JWH/kw Attachment cc:StewartD.Ebneter,RegionalAdministrator, RegionII,USNRCSeniorResidentInspector, USNRC,St.LuciePlantDAS/PSL0588-91P""A'j02VO~i8<s.',0rj.lrlanFPLGroupcon>panyy/P)

NRCSPECIALREPRTDIESELGENERATOR VALIDFAILUREOn29November1991at1101theSt.LucieUnitOne1BEmesgency DieselGenerator (EDG)wasstartedfortheweeklyoperational check.Operations notedthatupongenerator'excitation the'outputvoltagecontinued toclimbabovenominalvoltage.The1BEDGwasshutdownat1105anddeclaredoutofservice.The-1BEDGwasrestarted forcontinued.

troubleshooting.

Theproblemwasrepeatedforfurthertroubleshooting andthe1BEDGwasshutdownat1649.St.LucieUnitOnewasinarefueling shutdownandthe1BEDGwasnotrequiredtobeinserviceperTechnical Specification 3.8.1.2.Theproblemwastracedtothevoltageregulator circuit.Thefailedcomponent wastheautovoltageregulator card.Thevoltageregulator circuitisdesignedtoproducehighgenerator voltageintheeventofamalfunction ofthevoltageregulator circuit.Corrective Actions:Theautovoltageregulator cardwasreplacedandat1817thedieselgenerator wassuccessfully started.Thegenerator outputvoltagecontrolled normally.

Afterperforming theoperational checkthe1BEDGwasdeclaredbackinserviceat1824.The1BEDGwasunavailable forsevenhoursandnineteenminutes.FailureSummary:Thisisthethirdvalidfailureofthe1BEDGintheprevious20validtests.The1BEDGhasaccumulated 22validtestssincetheimplementation oftheTechnical Specification 3.8.1.1(July,1990).Thecurrentsurveillance intervalisoncepersevendaysperTechnical Specification 4.8.1.2.2.