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| | issue date = 04/24/1992 | | | issue date = 04/24/1992 |
| | title = In-House Event Rept 92-023:on 920421,turbine Generator Failed to Trip During Manual Reactor Trip.Root Cause Analysis Still in Progress.Solenoid Valves Removed & Sent to Independent Lab for Analysis | | | title = In-House Event Rept 92-023:on 920421,turbine Generator Failed to Trip During Manual Reactor Trip.Root Cause Analysis Still in Progress.Solenoid Valves Removed & Sent to Independent Lab for Analysis |
| | author name = SAGER D A | | | author name = Sager D |
| | author affiliation = FLORIDA POWER & LIGHT CO. | | | author affiliation = FLORIDA POWER & LIGHT CO. |
| | addressee name = | | | addressee name = |
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| =Text= | | =Text= |
| {{#Wiki_filter:ACCELERATED Dl/RIBUTION DEMONSTRATION SYSTEMREGULATORY INFORMATION DISTRIBUTIONSYSTEM(RIDS)ACCESSION NBR:9205010133 DOC.DATE: | | {{#Wiki_filter:ACCELERATED Dl/RIBUTION DEMONSTRATION SYSTEM REGULATORY INFORMATION DISTRI BUTION SYSTEM ( RI DS ) |
| 92/04/24NOTARIZED: | | ACCESSION NBR:9205010133 DOC.DATE: 92/04/24 NOTARIZED: NO DOCKET FACIL:50-389 St. Lucie Plant, Unit 2, Florida Power & Light Co. 05000389 AUTH. NAME . AUTHOR AFFILIATION SAGER,D.A. Florida Power & Light Co. |
| NOFACIL:50-389 St.LuciePlant,Unit2,FloridaPower&LightCo.AUTH.NAME.AUTHORAFFILIATION SAGER,D.A.
| | RECIP.NAME RECIPIENT AFFILIATION |
| FloridaPower&LightCo.RECIP.NAME RECIPIENT AFFILIATION
| | - Document Control Branch (Document Control Desk) |
| -DocumentControlBranch(Document ControlDesk)DOCKET05000389 | |
|
| |
|
| ==SUBJECT:== | | ==SUBJECT:== |
| In-HouseEventRept92-023:on 920421,turbine generator failedtotripduringmanualreactortrip.Rootcauseanalysisstillinprogress. | | In-House Event Rept 92-023:on 920421,turbine generator failed to trip during manual reactor trip. Root cause analysis still in progress. Solenoid valves removed & sent to independent lab for analysis. |
| Solenoidvalvesremoved&senttoindependent labforanalysis.
| | .DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR I ENCL TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc. |
| .DISTRIBUTION CODE:IE22DCOPIESRECEIVED:LTR IENCLlSIZE:TITLE:50.73/50.9 LicenseeEventReport(LER),IncidentRpt,etc.NOTES:RECIPIENT IDCODE/NAME PD2-2LANORRIS,JINTERNAL: | | NOTES: |
| ACNWAEOD/DOAAEOD/ROAB/DSP NRR/DLPQ/LHFB10 NRR/DOEA/OEAB NRR/DST/SELB 8D~/~S.TPLB8D1REGFILE02FILE01EXTERNAL:
| | l SIZE: |
| EG&GBRYCE,J.H NRCPDRNSICPOORE,W.COPIESLTTRENCL11112,21122111".'111,111111331111RECIPIENT IDCODE/NAME PD2-2PDACRSAEOD/DSP/TPAB NRR/DET/EMEB 7ENRR/DLPQ/LPEB10 NRR/DREP/PRPB11 NRR/DST/SICB8H3 NRR/DST/SRXB 8ERES/DSIR/EIB LSTLOBBYWARDNSICMURPHY,G.A NUDOCSFULLTXTCOPIESLTTRENCL11221111112211111'"111111DDDNOTETOALL"RIDS"RECIPIENTS:
| | RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL D PD2-2 LA 1 1 PD2-2 PD 1 1 NORRIS,J 1 1 D INTERNAL: ACNW AEOD/DOA 2, |
| PLEASEHELPUSTOREDUCEiVASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROOMPl-37(EXT.20079)TOELIMINATE YOURNAMEFROMDISTRIBUTION LISTSFORDOCUMENTS YOUDON'TNEED!TOTALNUMBEROFCOPIESREQUIRED:
| | 1 2 |
| LTTR32ENCL32DD P.O.Box128,Ft.Pierce,FL34954.0128 ggI4-8Q.L-92-129U.S.NuclearRegulatory Commission Attn:DocumentControlDeskWashington, D.C.20555'E:St.LucieUnit2DocketNo.50-389EventDate:April21,1992TurbineTriFailurePleasefindattachedthepreliminary internalproblemreportofourplanteventwhichoccurredonApril21,1992.Pursuantto10CFR50.73aLicensedEventReportwillbesubmitted within30daysoftheeventdate.Pleasecontactusifthereareanyquestions aboutthissubmittal.
| | 1 ACRS AEOD/DSP/TPAB 2 |
| Verytrulyyours,VicePresident St.LuciePlantDAS/JJB/kw cc:StewartD.Ebneter,RegionalAdministrator, RegionII,USNRCSeniorResidentInspector, USNRC,St.LuciePlantDAS/PSL4681-925'205010133 5'20424PDRADOCK05000385' PDRanFPLGroupcompany ST.LUCIEPLANTINHOUSEEVENTREPORT92-023TURBINEGENERATOR FAILEDTOTRIPFOLLOWING MANUALREACTORTRIPUNIT:2DATE:APRIL21,1992I.INITIALPLANTCONDITIONS OnApril21,1992,St.LucieUnit2wasshuttingdownforascheduled refueling outage.Reactorpowerwasatapproximately 12%.II.EVENTDESCRIPTION Ascheduled Reactor-Turbine shutdownwasinprogressonUnit2.Duringtheshutdown, powermovedtothetopofthecoreasexpected.
| | 1 2 |
| Existingprocedural guidanceonAxialShapeIndex(ASI)wasbeingemployedtominimizeitsaffects.WhenthreeoutoffourLocalPowerDensityPre-Trips onthcReactorProtection
| | 1 AEOD/ROAB/DSP 2 2 NRR/DET/EMEB 7E 1 1 NRR/DLPQ/LHFB10 1 1 NRR/DLPQ/LPEB10 1 1 NRR/DOEA/OEAB 1 ". '1 NRR/DREP/PRPB11 2 2 NRR/DST/SELB 8D 1 1, NRR/DST/SICB8H3 1 1 |
| .Systemcamein,theNuclearPlantSupervisor (NPS)instructed theReactorControlOperators tomanuallytriptheUnit.Amanualreactortripwasinitiated, buttheturbinedidnottrip.SeveralattemptsweremadetotriptheturbineusingtheTurbineTrippushbuttonwithnosuccessandthcNuclearWatchEngineertrippedtheturbinefromthefrontstandard. | | ~/~S.T PLB8D1 1 1 NRR/DST/SRXB 8E 1 ' 1 REG FILE 02 1 1 RES/DSIR/EIB 1 FILE 01 1 1 EXTERNAL: EG&G BRYCE,J.H 3 3 L ST LOBBY WARD "1 1 NRC PDR 1 1 NSIC MURPHY,G.A 1 1 NSIC POORE,W. 1 1 NUDOCS FULL TXT 1 1 D |
| III.EVENTSEQUENCESt.LucieUnit2wasperforming ascheduled reactorshutdownforrefueling purposes.
| | D D |
| DuringtheplantshutdownASIapproached itsupper(negative) limit.Coordination atcontrolling ASIwithinlimitsandmaintaining reactorcoolanttemperature duetoXenonbuildinginbecamemoredifficult.
| | NOTE TO ALL "RIDS" RECIPIENTS: |
| Whenreactorpowerwasdecreased toabout12%,controlrodinsertion hadnoeffectonmakingASIlessnegativeandthreeofthefourReactorProtection SystemLocalPowerDensitypre-tripscamein.Atthispoint,theNPSinstructed theReactorControlOperators tomanuallytriptheunitandthemanualreactortrippushbuttons onRTGB(ReactorTurbineGuageBoard)204andRTGB201weredepressed at0238withtheturbinetrippushbutton onRTGB201beingdepressed approximately twosecondslater;however,theturbinedidnottrip.StandardPostTripActionsfromEmergency Operating Procedure (EOP)1wereimplemented.
| | PLEASE HELP US TO REDUCE iVASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED! |
| Whentheturbinetrippushbutton wasdepressed, thcGovernorValvesindicated closedbuttheThrottleValves,ReheatValves,andIntercept Valvesindicated open.AutoStopOilandtheEmergency TripHeaderindicated pressures ofapproximately 100psiand2000psi,respectively.
| | TOTAL NUMBER OF COPIES REQUIRED: LTTR 32 ENCL 32 |
| Themegawattrecorderindicated ninetymegawatts.
| | |
| Severalmorcattemptsweremadetotriptheturbineusingthepushbutton, buttheywereunsuccessful.
| | P.O. Box 128, Ft. Pierce, FL 34954.0128 g g I 4-8Q. |
| Atthispoint,theReactorControlOperatoropenedtheGenerator outputBreakers8W52and8W49,securedthevoltageregulator, stoppedtheDigitalElectrohydraulic (DEH)pumps,closedtheMainStcamIsolation Valves(MSIV),andbrokecondenser vacuum.IHE¹92-023,4-24-92SHEET1OF3 III.EVENTSEQUENCE(cont'd)TheAssistant NuclearPlantSupervisor instructed theNuclearWatchEngineertotriptheturbinefromtheFrontStandard.
| | L-92-129 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555'E: |
| At0241alltheturbinevalvesclosed.EOP-2,ReactorTripRecovery, wasthencompleted wi'thtwosetsofsatisfactory Safety'unctionStatusChecks,theplantwasstabilized, andtheTurbineShutdownProcedure'as re-entered.
| | St. Lucie Unit 2 Docket No. 50-389 Event Date: April 21, 1992 Turbine Tri Failure Please find attached the preliminary internal problem report of our plant event which occurred on April 21, 1992. Pursuant to 10 CFR 50.73 a Licensed Event Report will be submitted within 30 days of the event date. |
| IV.EVENTEVALUATION A)PLANTRESPONSETheplantresponsetothiseventwasasexpectedwiththeexception ofthefailureoftheturbinetotrip.Uponthereactortripsignal,thefourControlElementDriveMechanism (CEDM)Busundervoltage relaysshouldde-energize. | | Please contact us if there are any questions about this submittal. |
| Thisshouldenergize(open)the20ETsolenoidvalveanddraintheelectro-hydraulic fluidfromtheemergency tripheader(Secattachment
| | Very truly yours, Vice President St. Lucie Plant DAS/JJB/kw cc: Stewart D. Ebneter, Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, St. Lucie Plant DAS/PSL 4681-92 5'205010133 5'20424 PDR ADOCK 05000385' PDR an FPL Group company |
| ¹I).The20ASTtripsolenoidcoilshouldsimultaneously | | |
| : energize, pulldownthemechanical triplever,anddumptheautostopoilheader.Decreasing autostopoilpressureallowstheInterface valvetoopenanddumptheelecto-hydraulic fluidemergency tripheader.Whenautostopoilpressuredecreases to45psi,pressureswitches63-1ASTand63-2ASTshouldlockin,actuating agenerator primarylockoutwhichtripsthegenerator outputbreakers.
| | ST. LUCIE PLANT IN HOUSE EVENT REPORT 92-023 TURBINE GENERATOR FAILED TO TRIP FOLLOWING MANUALREACTOR TRIP UNIT: 2 DATE: APRIL 21, 1992 I. INITIALPLANT CONDITIONS On April 21, 1992, St. Lucie Unit 2 was shutting down for a scheduled refueling outage. |
| Thesameresultshouldbeobtainedwhenattempting totriptheturbineviatheTurbineTripPushbutton.
| | Reactor power was at approximately 12%. |
| Amulti-discipline teamisinvestigating todetermine whytheturbinefailedtotripwhenthetripsignalswereinitiated.
| | II. EVENT DESCRIPTION A scheduled Reactor-Turbine shutdown was in progress on Unit 2. During the shutdown, power moved to the top of the core as expected. Existing procedural guidance on Axial Shape Index (ASI) was being employed to minimize its affects. |
| B)SAFETYSIGNIFICANCE Theplantresponsetothiseventisboundedbysection15.1.5ofthePSLUnit2FinalSafetyAnalysisReport(FSAR),"Increased HeatRemovalbytheSecondary System"as furtherdescribed below..12%PowerTrip,NoOperatorActionScenario. | | When three out of four Local Power Density Pre-Trips on thc Reactor Protection |
| MSIV'sautocloseat600psig.Cooldownterminated. | | .System came in, the Nuclear Plant Supervisor (NPS) instructed the Reactor Control Operators to manually trip the Unit. A manual reactor trip was initiated, but the turbine did not trip. Several attempts were made to trip the turbine using the Turbine Trip push button with no success and thc Nuclear Watch Engineer tripped the turbine from the front standard. |
| CoredecayheatreleasedviaMainSteamSafetyValves(MSSV)CooldownrateboundedbylimitingFSARcooldownevent.100%PowerTrip,NoOperatorActionScenario.
| | II I. EVENT SEQUENCE St. Lucie Unit 2 was performing a scheduled reactor shutdown for refueling purposes. During the plant shutdown ASI approached its upper (negative) limit. |
| PossibleSafetyInjection Actuation-Signal (SIAS)butnoactualinjection.
| | Coordination at controlling ASI within limits and maintaining reactor coolant temperature due to Xenon building in became more difficult. When reactor power was decreased to about 12%, control rod insertion had no effect on making ASI less negative and three of the four Reactor Protection System Local Power Density pre-trips came in. At this point, the NPS instructed the Reactor Control Operators to manually trip the unit and the manual reactor trip pushbuttons on RTGB (Reactor Turbine Guage Board) 204 and RTGB 201 were depressed at 0238 with the turbine trip pushbutton on RTGB 201 being depressed approximately two seconds later; however, the turbine did not trip. Standard Post Trip Actions from Emergency Operating Procedure (EOP) 1 were implemented. |
| Automatic MSIVclosureafter66seconds.FuelsRETRANanalysisvalidates thatnocoredamagewilloccur.100%PowerTripwithmultipleFSARChapter15AccidentScenario. | | When the turbine trip pushbutton was depressed, thc Governor Valves indicated closed but the Throttle Valves, Reheat Valves, and Intercept Valves indicated open. |
| Operators trainedonthesimulator formultiplefailureeventsbeyonddesignbasis.Excessstcamdemandeventsaresimulated andprocedurally addressed bytheEOP's.IHE¹92-023,4-24-92SHEET2OF3 IV.EVENTEVALUATION (cont'd)C)ROOTCAUSEANALYSIS Amulti-discipline TurbineInvestigation Teamisperforming arootcauseanalysisofthisevent.ALetterofInstruction, 2-LOI-T-67, "Evaluation ofTurbineSolenoidTripFunction," | | Auto Stop Oil and the Emergency Trip Header indicated pressures of approximately 100 psi and 2000 psi, respectively. The megawatt recorder indicated ninety megawatts. Several morc attempts were made to trip the turbine using the pushbutton, but they were unsuccessful. At this point, the Reactor Control Operator opened the Generator output Breakers 8W52 and 8W49, secured the voltage regulator, stopped the Digital Electrohydraulic (DEH) pumps, closed the Main Stcam Isolation Valves (MSIV), and broke condenser vacuum. |
| waswrittentoevaluatetheoperation oftheturbinemanualandautomatic tripfunctions.
| | IHE¹ 92-023, 4-24-92 SHEET 1 OF 3 |
| Deficiencies identified arenotedbelow.Rootcauseanalysisisstillinprogress. | | |
| D)DEFICIENCIES IDENTIFIED Testingofthc20ETTripsolenoid, 20ASTsolenoidvalve,andthe20OPC1and2solenoidvalveswasperformed inaccordance with2-LOI-T-67. | | III. EVENT SEQUENCE (cont'd) |
| Theresultsofthisevaluation areasfollows:1)20ETSolenoidvalveThcoriginalsolenoidvalvewasremovedtoprescrvcthe"asfound"condition ofthevalve.Anewsolenoidvalvewasinstalled andtestedsatisfactorily.
| | The Assistant Nuclear Plant Supervisor instructed the Nuclear Watch Engineer to trip the turbine from the Front Standard. At 0241 all the turbine valves closed. |
| Thisverifiedthe20ETelectrical circuitsdidnotcontribute tothefailures.
| | EOP-2, Reactor Trip Recovery, was then completed wi'th two sets of satisfactory Safety Status Checks, the plant was stabilized, and the Turbine Shutdown Procedure'as |
| 2)20ASTTripSolenoidThesolenoidwastestednumeroustimeswithtwoofthctestsindicative ofintermittent circuitproblems. | | 'unction re-entered. |
| Alooseconnection wasfoundonrelay62ASTX/pin6.Thisconnection isinthecircuitforall20ASTtripfunctions.
| | IV. EVENT EVALUATION A) PLANT RESPONSE The plant response to this event was as expected with the exception of the failure of the turbine to trip. Upon the reactor trip signal, the four Control Element Drive Mechanism (CEDM) Bus undervoltage relays should de-energize. This should energize (open) the 20 ET solenoid valve and drain the electro-hydraulic fluid from the emergency trip header ( Sec attachment ¹I). The 20 AST trip solenoid coil should simultaneously energize, pull down the mechanical trip lever, and dump the auto stop oil header. Decreasing auto stop oil pressure allows the Interface valve to open and dump the electo-hydraulic fluid emergency trip header. When auto stop oil pressure decreases to 45 psi, pressure switches 63-1 AST and 63-2 AST should lock in, actuating a generator primary lockout which trips the generator output breakers. |
| Furthertroubleshooting iscontinuing.
| | The same result should be obtained when attempting to trip the turbine via the Turbine Trip Pushbutton. A multi-discipline team is investigating to determine why the turbine failed to trip when the trip signals were initiated. |
| 3)20OPC1and2SolenoidValvesOneOPCsoleniodvalvewasremovedpriortotestingforpotential failuremodeanalysis. | | B) SAFETY SIGNIFICANCE The plant response to this event is bounded by section 15.1.5 of the PSL Unit 2 Final Safety Analysis Report (FSAR), "Increased Heat Removal by the Secondary System"as further described below.. |
| Testingofoneoriginalandoncreplacement OPCsolenoidvalveindicated acceptable operation oftheOPCcircuits.
| | 12% Power Trip, No Operator Action Scenario. |
| V.CORRECTIVE ACTIONS1.Theoriginal20ET,20OPC-1and20OPC-2Solenoidvalveshavebeenremovedandweresenttoanindependent laboratory foranalysis. | | MSIV's auto close at 600 psig. Cooldown terminated. |
| 2.Maintenance iscontinuing toinvestigate thcrootcauseoftheintermittent electrical problemsofthc20ASTTripSolenoid. | | Core decay heat released via Main Steam Safety Valves (MSSV) |
| Thecircuitsofthe20ETand20OPC1and2Solenoids arealsobeingevaluated toensuresimilarproblemsdonotexist.3.NuclearFuelsisevaluating additional guidanceforASIcontrolattheendofcorelife.4.Operations isevaluating additional guidanceforEOP-1,"Standard PostTripActions",
| | Cooldown rate bounded by limiting FSAR cooldown event. |
| onactionstotakeforareactortripwithnosubsequent turbinetrip.IHE¹92-023,4-24-92SHEET3OF3 eWESTINGHOUSE ELECTRO-HYDRAULIC CONTROLSYSTEMANDAUTO-STOP OILSYSTEM~esattttTrtvttvvaalralSCOPL5'7~\rtactttvatvttvtaltarwaavtawaTJtrttvtattaawwwatalarTTLTagZ~~4la~stasttw~slasILWTatTttasttwSavtrgEMERGENCY TRIPSIIIIIIII3IIIlIIIlIIIIIlIIIIIIIlIItwaatwrI~~QOg7~Ttawtaa~aII~tsttataca'vaLva AUTOSTOPOILPRESSURESWITCHES(3)~acevaLTC~vaatratatalaI~tLava~I~avt1.LOWAUTO-STOP OILPRESSURE(2/3)2.REACTORTRIP('I)3.MANUALTRIP4.HI-HlLEVELINANYS/GSOLENOIDTRIPS1.REACTORTRIP(A)2.ELECTRICAL OVERSPEED
| | 100% Power Trip, No Operator Action Scenario. |
| ~3.LOWEHFLUIDPRESSURE4.MANUAL5.ETC.vaccwtavLaoaaa.OL~tattatat/2o-iOPcQo-2opg0roasf0Itat~tLOvsaaaaatvaOVERSPEED PROTECTION CONTROLLER 103KOFNORMALSPEED2.GENERATOR OUTPUTBREAKERSOPENABOVEAPRESETPOWERLEVEL3.CHANGEINGENERATOR OUTPUTANDTURBINEINLETPRESSUREAVIOIIOPOILSY5ICII}}
| | Possible Safety Injection Actuation-Signal (SIAS) but no actual injection. |
| | Automatic MSIV closure after 66 seconds. |
| | Fuels RETRAN analysis validates that no core damage will occur. |
| | 100% Power Trip with multiple FSAR Chapter 15 Accident Scenario. |
| | Operators trained on the simulator for multiple failure events beyond design basis. |
| | Excess stcam demand events are simulated and procedurally addressed by the EOP's. |
| | IHE¹ 92-023, 4-24-92 SHEET 2 OF 3 |
| | |
| | IV. EVENT EVALUATION(cont'd) |
| | C) ROOT CAUSEANALYSIS A multi-discipline Turbine Investigation Team is performing a root cause analysis of this event. A Letter of Instruction, 2-LOI-T-67, "Evaluation of Turbine Solenoid Trip Function," was written to evaluate the operation of the turbine manual and automatic trip functions. Deficiencies identified are noted below. Root cause analysis is still in progress. |
| | D) DEFICIENCIES IDENTIFIED Testing of thc 20 ET Trip solenoid, 20 AST solenoid valve, and the 20 OPC 1 and 2 solenoid valves was performed in accordance with 2-LOI-T-67. The results of this evaluation are as follows: |
| | : 1) 20 ET Solenoid valve Thc original solenoid valve was removed to prescrvc the "as found" condition of the valve. A new solenoid valve was installed and tested satisfactorily. This verified the 20 ET electrical circuits did not contribute to the failures. |
| | : 2) 20 AST Trip Solenoid The solenoid was tested numerous times with two of thc tests indicative of intermittent circuit problems. A loose connection was found on relay 62 ASTX / pin 6. This connection is in the circuit for all 20 AST trip functions. |
| | Further troubleshooting is continuing. |
| | : 3) 20 OPC 1 and 2 Solenoid Valves One OPC soleniod valve was removed prior to testing for potential failure mode analysis. Testing of one original and onc replacement OPC solenoid valve indicated acceptable operation of the OPC circuits. |
| | V. CORRECTIVE ACTIONS |
| | : 1. The original 20 ET, 20 OPC-1 and 20 OPC-2 Solenoid valves have been removed and were sent to an independent laboratory for analysis. |
| | : 2. Maintenance is continuing to investigate thc root cause of the intermittent electrical problems of thc 20 AST Trip Solenoid. The circuits of the 20 ET and 20 OPC 1 and 2 Solenoids are also being evaluated to ensure similar problems do not exist. |
| | : 3. Nuclear Fuels is evaluating additional guidance for ASI control at the end of core life. |
| | : 4. Operations is evaluating additional guidance for EOP-1, "Standard Post Trip Actions", on actions to take for a reactor trip with no subsequent turbine trip. |
| | IHE¹ 92-023, 4-24-92 SHEET 3 OF 3 |
| | |
| | e WESTINGHOUSE ELECTRO-HYDRAULIC CONTROL SYSTEM AND AUTO-STOP OIL SYSTEM EMERGENCY TRIPS |
| | : 1. LOW AUTO-STOP OIL PRESSURE (2/3) |
| | ~ esatttt |
| | : 2. REACTOR TRIP ('I) |
| | Trtvt 3. MANUAL TRIP SOLENOID TRIPS tvvaalra lS I I 4. HI-Hl LEVEL IN ANY S/G |
| | ~4 I |
| | I I |
| | I I |
| | 1 . REACTOR TRIP (A) |
| | : 2. ELECTRICAL OVERSPEED |
| | : 3. LOW EH FLUID PRESSURE |
| | ~ |
| | I 4. MANUAL wwat alar stasttw TTLTa |
| | ~ 3 I |
| | : 5. ETC. |
| | I vaccw Z~ I tav g la l AUTO STOP OIL I PRESSURE SWITCHES CO P L I |
| | I (3) ~tatta Lao aa a. OL tat/ |
| | l ~ ace vaLTC ~ |
| | ~ \rtact tt vatvt I tvt altar w I I I I l I I I I I aavt awa ~ s las ILW I T Jtrt 5'7 tvt at taa w I l Tat Tt I I twaatwr I~~QO g7 tas ttw Iv atatra t a t ala Lava ~ |
| | Savtr a |
| | ~ |
| | g ~ |
| | ~ Ttawtaa I I I ~tsttataca'vaLva ~ avt 2o-i OPc 0 ro Ovsaaaaa tva Qo-2 opg asf 0 Itat |
| | ~ tL OVERSPEED PROTECTION CONTROLLER 103K OF NORMAL SPEED AVIO IIOPOILSY5ICII |
| | : 2. GENERATOR OUTPUT BREAKERS OPEN ABOVE A PRESET POWER LEVEL |
| | : 3. CHANGE IN GENERATOR OUTPUT AND TURBINE INLET PRESSURE}} |
|
|---|
Category:REPORTABLE OCCURRENCE REPORT (SEE ALSO AO
MONTHYEARML17229A7401998-05-26026 May 1998
Special Rept:On 980507,declared Plant Meteorological Tower Ten Meter Wind Speed Indicator Inoperable Due to Loss of Indicator.Tightened Loose Ground Wire Connection & Returned Indicator to Service
ML17229A4981997-10-17017 October 1997
Special Rept:On 970921,discovered That Several Heated Juction Thermocouple Inputs to Channel B of Rvlm Sys Deviating from Normal Temps.Rvlm Sys Will Be Restored to Operability Before End of Next Unit 2 Refueling Outage
ML17229A4421997-08-0808 August 1997
Special Rept:On 970731,determined That Use of Conservative Min Value for Pin/Box Factor in Analysis of Record,Compared to Actual Value of Cycle 10 Min Pin/Box Factor,Introduced Conservation of .0073 in Energy Redistribution Factors
ML17228B2661995-09-11011 September 1995
Special Rept:On 950812,post Hurricane Erin Beach Dune Survey Performed.Average Values of Results Greater than or within Range Provided in St Lucie Unit 1 Final Usar,Section 2.4.2.2 & Acceptable
ML17228B2111995-07-0606 July 1995
Special Rept:On 950606,1A EDG Automatically Tripped on High Water Jacket Temp.Caused by Misapplication of Calibration Test Equipment for Temp Switch.Temp Switch Replaced
ML17228B1761995-06-17017 June 1995
Special Rept:On 950517,1B EDG Engine Start Failure Alarm Sounded 30 Min Into Surveillance Run.Caused by Failure of One cylinder.1B EDG Declared Out of Svc.Failed Governer Assembly Replaced.Failed Assembly Sent Out for Insp
ML17228A9781995-01-0909 January 1995
Special Rept:On 941214,2A Emergency Diesel Generator Failed. Caused by Excessive Clearance Between Speed Adjusting Shaft & Shaft Bushing.Electrical Maint Replaced Failed Governor/ Actuator Assembly on 2A2 EDG
ML17228A9171994-11-23023 November 1994
Special Rept:On 941028,EDG Failure Occurred Due to Burned Through Wire from Magnetic Amplifier Terminal Block to Field.Wire Repaired & Relanded to Terminal Block
ML17228A8521994-09-0909 September 1994
Special Rept:On 940823 & 25,RAB Exhaust Sys WRGM RM-26-90 Declared Out of Svc.Caused by Intermittment Communication Due to Power Supply Regulator Failure.Chemistry Procedure C-93 Implemented & Portable Monitor Installed
ML17228A5891994-06-0202 June 1994
Special Rept:On 940504,non-valid Failure of EDG 1A Occurred Due to Spurious Actuation of High Water Jacket Temp Switch (Designated TS-59-003A).Subj Switch Replaced W/New Model 9025G & EDG 1A Declared Back in Svc on 940505
ML17228A4881994-03-0101 March 1994
Special Rept:On 920424,EDG 1B Failed Due to Failed Fan Idler Shaft.Caused by Inadequate Design.Radiation Fan Idler Shaft on Both 1A & 1B EDGs Replaced
ML17228A1331993-04-19019 April 1993
Special Rept:On 930310,longitudinal Channel of Common Seismic Monitor Recorder & Indicator Declared Out of Svc & Remained Out of Svc Longer than Allowed by Ts.Util Awaiting Repairs to Instruments by Vendor
ML17227A7731993-03-22022 March 1993
Special Rept:On 930307,SG Blowdown Treatment Facility Bldg Exhaust Sys Radiation Monitor Failed Functional Test & Declared Inoperable.Monitor Out of Svc for More than 72 H Due to Repair Problems.Detector Repaired & Placed in Svc
ML17227A6881993-01-14014 January 1993
Special Rept:On 921208,channel 7 of Loose Parts Monitoring Sys Declared Out of Svc Due to Excessive Electrical Noise Received at Preamplifier for More than 30 Days.Complete Channel Calibr Performed.Channel 8 Still Available
ML17227A6631992-12-14014 December 1992
Revised Special Rept:On 920630,DG 1A Declared Out of Svc in Order to Perform Preventive Maint on Air Start Sys.On 920701 DG Tripped Due to High Water Jacket Temp.Temp Switch TS-59-003A Replaced W/New Switch
ML17227A5211992-07-27027 July 1992
Special Rept:On 920630,DG 1A Declared Out of Svc in Order to Perform Preventative Maint on Air Start Sys.Caused by Spurious Operation of Trip Which Is Bypassed in Emergency Operating Mode.Temp Switches Repaired & Reinstalled
ML17227A4241992-05-14014 May 1992
Special Rept:On 920421,turbine Generator Failed to Trip Following Manual Reactor Trip.Caused by Failures in Redundant & Electrically Independent Turbine Tripping Schemes.I&C Disassembled & Trip Block Inspected
ML17227A4031992-04-28028 April 1992
Special Rept:On 920403,EDG 1B Output Breaker Would Not Close During Weekly Operational Check.Caused by Failure of Underfrequency Permissive Circuit Relay.Failed Relay Replaced & EDG Successfully Started
ML17227A4021992-04-24024 April 1992
In-House Event Rept 92-023:on 920421,turbine Generator Failed to Trip During Manual Reactor Trip.Root Cause Analysis Still in Progress.Solenoid Valves Removed & Sent to Independent Lab for Analysis
ML17223B3931991-12-20020 December 1991
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
ML17223B3201991-11-13013 November 1991
Special Rept:On 911021 & 22,1B EDG Failed During 24 Hr Surveillance Runs.First Failure Caused by Broken Shaft Due to Fatigue at High Stress Location.New Shaft,Of Modified Design,Installed.Run Performed Satisfactorily on 911027
ML17223B2401991-08-0606 August 1991
Special Rept:On 910705,valid Failure of Emergency Diesel Generator 1A Occurred.Caused by Damaged Bodine Motor. Damaged Motor Replaced
ML17223B2331991-07-26026 July 1991
Special Rept:On 910626,failure of 2B Emergency Diesel Generator Occurred During post-maint Testing Following Implementation of Plant Mod.Caused by Failed Relay.Relay R1X1 Replaced
ML17223B2111991-06-0606 June 1991
Special Rept:On 910513,determined That Plant Criteria for Fishkill Had Been Met.Cause of Mortality Is Insufficient Food Supply.Fish Removed & Disposed of on Site & Velocity Caps Rebuilt
ML17223B1681991-04-17017 April 1991
Special Rept:On 910320,1B Emergency Diesel Generator (DG) Nonvalid Failure Occurred Due to Circuitry Failure of DG Synchronizing Circuitry.Relay Exhibiting Binding Calibr & Will Be Replaced
ML17223B1051991-02-15015 February 1991
Special Rept:On 910116,troubleshooting Revealed Defective Limit Switch Assembly on 2B2 Governor of Edg.Switch Assembly Replaced & 2B EDG Successfully Retested.Sys Engineer Will Track Limit Switch for Each EDG
ML17223B0571991-01-0707 January 1991
Special Rept:On 901130,loose Parts Monitor Declared Out of Svc for More than 30 Days.Caused by Presence of Large Hz Signal.Troubleshooting Efforts Will Resume on Inaccessible Areas of Sys During Next Available Opportinity
ML17223A6541990-05-15015 May 1990
Special Rept:On 900405,loose Parts Detection Sys Channel out-of-svc for Greater than 30 Days.Cause of Failure Not Determined.Efforts Continuing to Identify Source of Electrical Noise & Mechanism for Induction Into Sys
ML17223A5421990-03-0202 March 1990
Special Rept:On 900103,emergency Diesel Generator 2A Experienced Load Control Problems.Caused by Loose Connections in Governor Load Sensor Circuit.Loose Connections Tightened & Replacement Relay Installed
ML17223A1621989-06-0505 June 1989
Special Rept:On 890406,emergency Diesel Generator 2A Failed. Caused by Thrust Bearing Failure Due to Excessive Clearance Between Bearing Collar & Fan Shaft.Cooling Fan Blades & Shroud Repaired
ML17222A7711989-04-27027 April 1989
Special Rept:On 890315,diesel Tripped on High Crankcase Pressure.Caused by Engine Design.Pressure Trip Reset,But Output Breaker Failed to Close.Faulty Voltage Monitoring Relay Replaced.On 890321,same Diesel Generator Tripped
ML17222A7331989-03-20020 March 1989
Special Rept:On 890117 & 0203,emergency Diesel Generators 2A & 2B Failed.Diesel Trip Caused by Engine Design.Oil Splash Guards Will Be Installed on All Plant Diesels & Step Added to ESF Test Procedure
ML17221A6871988-03-25025 March 1988
Special Rept:On 880314,steam Generator Blowdown Bldg Exhaust Noble Gas Radiation Monitor Failed.Caused by Failed Central Processing Unit Processor Board.Portable Particulate,Iodine & Noble Gas Monitor Installed Until New Monitor in Place
ML17221A6421988-02-19019 February 1988
Special Rept:On 880112,emergency Diesel Generator 2A Failed to Start.Caused by Failed Speed Setting Bodine Motor on 12 Cylinder Engine Governor.Motor Replaced & Generator Returned to Svc
ML17221A5001987-11-0909 November 1987
Special Rept:On 871005,emergency Diesel Generator 2B Took Greater than 17 to Start Up & Load Onto Bus.Caused by Failure of Governor of Engines.Mechanical Section of Governor Replaced
ML17221A4541987-10-19019 October 1987
Special Rept:On 870902,General Motors Emergency Diesel Generator Failed to Start.Caused by 12-cylinder Engine Actuator Friction Clutch Assembly Out of Adjustment.Clutch Assembly Adjusted
ML17219A6741987-07-0606 July 1987
Special Rept:On 870609,personnel Discovered That Less than Required Number of Sensors in One of Two Available Reactor Vessel Level Monitoring Sys Channels Operable.Caused by Personnel Error & Deficiency in Surveillance Procedure
ML17219A6661987-07-0101 July 1987
Special Rept:On 870528,city Water Tank 1B Declared Inoperable for More than 7 Days in Violation of Tech Specs to Perform Necessary Maint.Caused by Necessary Repairs to Protective Coating Sys to Prevent Further Corrosion
ML17216A5551986-05-0707 May 1986
Special Rept:On 860312,alarm Received Indicating That Diesel Engine Failed to Start.Caused by Insufficient Torqued Nut. on 860326,diesel Generator Tripped on High Crankcase Pressure.Caused by Oil Splashing on Pressure Switch
ML17301A1501985-01-21021 January 1985
Special Rept:On 841220,during Surveillance Run of Diesel Generator 2B While Unit Shut Down,Radiator Cooling Fan Hub Found Loosened & Cracked Circumferentially.Mod Issued to Eliminate Possibility of Set Screw Loosening
ML20023C4091983-05-0909 May 1983
RO 389-83-005:on 830507,safety Injection Tank Isolation Valves Closed W/Plant in Mode 4 Above 276 Psia.Caused by Personnel Error.Procedural Step Overlooked During Plant Heatup.Valves Immediately Opened
ML20011A7991981-10-26026 October 1981
RO 335-81-46:steam Generator Tube Eddy Current Test Performed in Ctr Area of B Steam Generator to Confirm Leak Located by Helium Test.Cause Not Stated.Testing of Rows 1-18 Will Be Completed within 2 to 3 Days
ML17266A4521981-04-24024 April 1981
RO 335-81-19:on 810410,notification Made to NRC of Analyses Utilizing FSAR Assumptions for Certain Postulated Accidents Using Assumption That Reactor Coolant Pressure Tripped Upon Receipt of Sias.Item Determined Not Reportable
ML17209A7121980-12-19019 December 1980
RO 80-003:on 801202,ocean Intake Area Recording Thermograph Sys Reported Lost.Probably Caused by Storm Surge Wave Action or Commercial Fishing.Sys Replaced on 801210
ML20003B6641980-12-19019 December 1980
Nonroutine Environ Operating Rept 335-B-80-03:on 801202, Ocean Intake Area Recording Thermograph Sys Was Reported Missing.Probably Caused by Storm Surge Wave Action or Commercial Fishing.Sys Was Replaced on 801210
ML17266A2161980-06-11011 June 1980
RO 335-80-29:on 800611,ground Occurred on Bus 1B Dc Causing Containment Isolation Valve HCV-14-6 to Fail Closed. Apparently Caused by Water in Solenoid from Steam Leak. Cooldown Continuing.Damaged Valve Seals Will Be Replaced
ML17266A2111980-05-15015 May 1980
RO 335-80-27:on 800514,C-E Informed Util That Partial Draining of RCS While in Mode 5 Is Condition Not Analyzed for Boron Dilution Event.Plant Operating Procedures Revised to Increase Shutdown Margin
ML17266A2041980-05-12012 May 1980
RO 335-80-25:on 800512,during Planned Secondary Plant Cooldown/Depressurization for Turbine Steam Seal Repair, Main Steam Header Would Not Depressurize Following MSIV Closure.Apparently Caused by Mispositioned Valve
ML17208A5541980-04-29029 April 1980
RO 335-80-17:on 800428,cracks Were Found to Occur at Same Location on Stainless Steel Socket Welded Elbows During Installation in Secondary Sys.Caused by Defective Fittings. All Identical Fittings Were Inspected & Found Satisfactory
ML17266A1981980-04-14014 April 1980
Ro:On 800411,determination Made That Rosemount Model 1152 Pressure Transmitters,Which Actuate Containment Vacuum Relief Valves FCV-25-7 & FCV-25-8,may Be Defective.Cause Not Stated.Transmitters Will Be Replaced
1998-05-26
[Table view]
Category:LER)
MONTHYEARML17229A7401998-05-26026 May 1998
Special Rept:On 980507,declared Plant Meteorological Tower Ten Meter Wind Speed Indicator Inoperable Due to Loss of Indicator.Tightened Loose Ground Wire Connection & Returned Indicator to Service
ML17229A4981997-10-17017 October 1997
Special Rept:On 970921,discovered That Several Heated Juction Thermocouple Inputs to Channel B of Rvlm Sys Deviating from Normal Temps.Rvlm Sys Will Be Restored to Operability Before End of Next Unit 2 Refueling Outage
ML17229A4421997-08-0808 August 1997
Special Rept:On 970731,determined That Use of Conservative Min Value for Pin/Box Factor in Analysis of Record,Compared to Actual Value of Cycle 10 Min Pin/Box Factor,Introduced Conservation of .0073 in Energy Redistribution Factors
ML17228B2661995-09-11011 September 1995
Special Rept:On 950812,post Hurricane Erin Beach Dune Survey Performed.Average Values of Results Greater than or within Range Provided in St Lucie Unit 1 Final Usar,Section 2.4.2.2 & Acceptable
ML17228B2111995-07-0606 July 1995
Special Rept:On 950606,1A EDG Automatically Tripped on High Water Jacket Temp.Caused by Misapplication of Calibration Test Equipment for Temp Switch.Temp Switch Replaced
ML17228B1761995-06-17017 June 1995
Special Rept:On 950517,1B EDG Engine Start Failure Alarm Sounded 30 Min Into Surveillance Run.Caused by Failure of One cylinder.1B EDG Declared Out of Svc.Failed Governer Assembly Replaced.Failed Assembly Sent Out for Insp
ML17228A9781995-01-0909 January 1995
Special Rept:On 941214,2A Emergency Diesel Generator Failed. Caused by Excessive Clearance Between Speed Adjusting Shaft & Shaft Bushing.Electrical Maint Replaced Failed Governor/ Actuator Assembly on 2A2 EDG
ML17228A9171994-11-23023 November 1994
Special Rept:On 941028,EDG Failure Occurred Due to Burned Through Wire from Magnetic Amplifier Terminal Block to Field.Wire Repaired & Relanded to Terminal Block
ML17228A8521994-09-0909 September 1994
Special Rept:On 940823 & 25,RAB Exhaust Sys WRGM RM-26-90 Declared Out of Svc.Caused by Intermittment Communication Due to Power Supply Regulator Failure.Chemistry Procedure C-93 Implemented & Portable Monitor Installed
ML17228A5891994-06-0202 June 1994
Special Rept:On 940504,non-valid Failure of EDG 1A Occurred Due to Spurious Actuation of High Water Jacket Temp Switch (Designated TS-59-003A).Subj Switch Replaced W/New Model 9025G & EDG 1A Declared Back in Svc on 940505
ML17228A4881994-03-0101 March 1994
Special Rept:On 920424,EDG 1B Failed Due to Failed Fan Idler Shaft.Caused by Inadequate Design.Radiation Fan Idler Shaft on Both 1A & 1B EDGs Replaced
ML17228A1331993-04-19019 April 1993
Special Rept:On 930310,longitudinal Channel of Common Seismic Monitor Recorder & Indicator Declared Out of Svc & Remained Out of Svc Longer than Allowed by Ts.Util Awaiting Repairs to Instruments by Vendor
ML17227A7731993-03-22022 March 1993
Special Rept:On 930307,SG Blowdown Treatment Facility Bldg Exhaust Sys Radiation Monitor Failed Functional Test & Declared Inoperable.Monitor Out of Svc for More than 72 H Due to Repair Problems.Detector Repaired & Placed in Svc
ML17227A6881993-01-14014 January 1993
Special Rept:On 921208,channel 7 of Loose Parts Monitoring Sys Declared Out of Svc Due to Excessive Electrical Noise Received at Preamplifier for More than 30 Days.Complete Channel Calibr Performed.Channel 8 Still Available
ML17227A6631992-12-14014 December 1992
Revised Special Rept:On 920630,DG 1A Declared Out of Svc in Order to Perform Preventive Maint on Air Start Sys.On 920701 DG Tripped Due to High Water Jacket Temp.Temp Switch TS-59-003A Replaced W/New Switch
ML17227A5211992-07-27027 July 1992
Special Rept:On 920630,DG 1A Declared Out of Svc in Order to Perform Preventative Maint on Air Start Sys.Caused by Spurious Operation of Trip Which Is Bypassed in Emergency Operating Mode.Temp Switches Repaired & Reinstalled
ML17227A4241992-05-14014 May 1992
Special Rept:On 920421,turbine Generator Failed to Trip Following Manual Reactor Trip.Caused by Failures in Redundant & Electrically Independent Turbine Tripping Schemes.I&C Disassembled & Trip Block Inspected
ML17227A4031992-04-28028 April 1992
Special Rept:On 920403,EDG 1B Output Breaker Would Not Close During Weekly Operational Check.Caused by Failure of Underfrequency Permissive Circuit Relay.Failed Relay Replaced & EDG Successfully Started
ML17227A4021992-04-24024 April 1992
In-House Event Rept 92-023:on 920421,turbine Generator Failed to Trip During Manual Reactor Trip.Root Cause Analysis Still in Progress.Solenoid Valves Removed & Sent to Independent Lab for Analysis
ML17223B3931991-12-20020 December 1991
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
ML17223B3201991-11-13013 November 1991
Special Rept:On 911021 & 22,1B EDG Failed During 24 Hr Surveillance Runs.First Failure Caused by Broken Shaft Due to Fatigue at High Stress Location.New Shaft,Of Modified Design,Installed.Run Performed Satisfactorily on 911027
ML17223B2401991-08-0606 August 1991
Special Rept:On 910705,valid Failure of Emergency Diesel Generator 1A Occurred.Caused by Damaged Bodine Motor. Damaged Motor Replaced
ML17223B2331991-07-26026 July 1991
Special Rept:On 910626,failure of 2B Emergency Diesel Generator Occurred During post-maint Testing Following Implementation of Plant Mod.Caused by Failed Relay.Relay R1X1 Replaced
ML17223B2111991-06-0606 June 1991
Special Rept:On 910513,determined That Plant Criteria for Fishkill Had Been Met.Cause of Mortality Is Insufficient Food Supply.Fish Removed & Disposed of on Site & Velocity Caps Rebuilt
ML17223B1681991-04-17017 April 1991
Special Rept:On 910320,1B Emergency Diesel Generator (DG) Nonvalid Failure Occurred Due to Circuitry Failure of DG Synchronizing Circuitry.Relay Exhibiting Binding Calibr & Will Be Replaced
ML17223B1051991-02-15015 February 1991
Special Rept:On 910116,troubleshooting Revealed Defective Limit Switch Assembly on 2B2 Governor of Edg.Switch Assembly Replaced & 2B EDG Successfully Retested.Sys Engineer Will Track Limit Switch for Each EDG
ML17223B0571991-01-0707 January 1991
Special Rept:On 901130,loose Parts Monitor Declared Out of Svc for More than 30 Days.Caused by Presence of Large Hz Signal.Troubleshooting Efforts Will Resume on Inaccessible Areas of Sys During Next Available Opportinity
ML17223A6541990-05-15015 May 1990
Special Rept:On 900405,loose Parts Detection Sys Channel out-of-svc for Greater than 30 Days.Cause of Failure Not Determined.Efforts Continuing to Identify Source of Electrical Noise & Mechanism for Induction Into Sys
ML17223A5421990-03-0202 March 1990
Special Rept:On 900103,emergency Diesel Generator 2A Experienced Load Control Problems.Caused by Loose Connections in Governor Load Sensor Circuit.Loose Connections Tightened & Replacement Relay Installed
ML17223A1621989-06-0505 June 1989
Special Rept:On 890406,emergency Diesel Generator 2A Failed. Caused by Thrust Bearing Failure Due to Excessive Clearance Between Bearing Collar & Fan Shaft.Cooling Fan Blades & Shroud Repaired
ML17222A7711989-04-27027 April 1989
Special Rept:On 890315,diesel Tripped on High Crankcase Pressure.Caused by Engine Design.Pressure Trip Reset,But Output Breaker Failed to Close.Faulty Voltage Monitoring Relay Replaced.On 890321,same Diesel Generator Tripped
ML17222A7331989-03-20020 March 1989
Special Rept:On 890117 & 0203,emergency Diesel Generators 2A & 2B Failed.Diesel Trip Caused by Engine Design.Oil Splash Guards Will Be Installed on All Plant Diesels & Step Added to ESF Test Procedure
ML17221A6871988-03-25025 March 1988
Special Rept:On 880314,steam Generator Blowdown Bldg Exhaust Noble Gas Radiation Monitor Failed.Caused by Failed Central Processing Unit Processor Board.Portable Particulate,Iodine & Noble Gas Monitor Installed Until New Monitor in Place
ML17221A6421988-02-19019 February 1988
Special Rept:On 880112,emergency Diesel Generator 2A Failed to Start.Caused by Failed Speed Setting Bodine Motor on 12 Cylinder Engine Governor.Motor Replaced & Generator Returned to Svc
ML17221A5001987-11-0909 November 1987
Special Rept:On 871005,emergency Diesel Generator 2B Took Greater than 17 to Start Up & Load Onto Bus.Caused by Failure of Governor of Engines.Mechanical Section of Governor Replaced
ML17221A4541987-10-19019 October 1987
Special Rept:On 870902,General Motors Emergency Diesel Generator Failed to Start.Caused by 12-cylinder Engine Actuator Friction Clutch Assembly Out of Adjustment.Clutch Assembly Adjusted
ML17219A6741987-07-0606 July 1987
Special Rept:On 870609,personnel Discovered That Less than Required Number of Sensors in One of Two Available Reactor Vessel Level Monitoring Sys Channels Operable.Caused by Personnel Error & Deficiency in Surveillance Procedure
ML17219A6661987-07-0101 July 1987
Special Rept:On 870528,city Water Tank 1B Declared Inoperable for More than 7 Days in Violation of Tech Specs to Perform Necessary Maint.Caused by Necessary Repairs to Protective Coating Sys to Prevent Further Corrosion
ML17216A5551986-05-0707 May 1986
Special Rept:On 860312,alarm Received Indicating That Diesel Engine Failed to Start.Caused by Insufficient Torqued Nut. on 860326,diesel Generator Tripped on High Crankcase Pressure.Caused by Oil Splashing on Pressure Switch
ML17301A1501985-01-21021 January 1985
Special Rept:On 841220,during Surveillance Run of Diesel Generator 2B While Unit Shut Down,Radiator Cooling Fan Hub Found Loosened & Cracked Circumferentially.Mod Issued to Eliminate Possibility of Set Screw Loosening
ML20023C4091983-05-0909 May 1983
RO 389-83-005:on 830507,safety Injection Tank Isolation Valves Closed W/Plant in Mode 4 Above 276 Psia.Caused by Personnel Error.Procedural Step Overlooked During Plant Heatup.Valves Immediately Opened
ML20011A7991981-10-26026 October 1981
RO 335-81-46:steam Generator Tube Eddy Current Test Performed in Ctr Area of B Steam Generator to Confirm Leak Located by Helium Test.Cause Not Stated.Testing of Rows 1-18 Will Be Completed within 2 to 3 Days
ML17266A4521981-04-24024 April 1981
RO 335-81-19:on 810410,notification Made to NRC of Analyses Utilizing FSAR Assumptions for Certain Postulated Accidents Using Assumption That Reactor Coolant Pressure Tripped Upon Receipt of Sias.Item Determined Not Reportable
ML17209A7121980-12-19019 December 1980
RO 80-003:on 801202,ocean Intake Area Recording Thermograph Sys Reported Lost.Probably Caused by Storm Surge Wave Action or Commercial Fishing.Sys Replaced on 801210
ML20003B6641980-12-19019 December 1980
Nonroutine Environ Operating Rept 335-B-80-03:on 801202, Ocean Intake Area Recording Thermograph Sys Was Reported Missing.Probably Caused by Storm Surge Wave Action or Commercial Fishing.Sys Was Replaced on 801210
ML17266A2161980-06-11011 June 1980
RO 335-80-29:on 800611,ground Occurred on Bus 1B Dc Causing Containment Isolation Valve HCV-14-6 to Fail Closed. Apparently Caused by Water in Solenoid from Steam Leak. Cooldown Continuing.Damaged Valve Seals Will Be Replaced
ML17266A2111980-05-15015 May 1980
RO 335-80-27:on 800514,C-E Informed Util That Partial Draining of RCS While in Mode 5 Is Condition Not Analyzed for Boron Dilution Event.Plant Operating Procedures Revised to Increase Shutdown Margin
ML17266A2041980-05-12012 May 1980
RO 335-80-25:on 800512,during Planned Secondary Plant Cooldown/Depressurization for Turbine Steam Seal Repair, Main Steam Header Would Not Depressurize Following MSIV Closure.Apparently Caused by Mispositioned Valve
ML17208A5541980-04-29029 April 1980
RO 335-80-17:on 800428,cracks Were Found to Occur at Same Location on Stainless Steel Socket Welded Elbows During Installation in Secondary Sys.Caused by Defective Fittings. All Identical Fittings Were Inspected & Found Satisfactory
ML17266A1981980-04-14014 April 1980
Ro:On 800411,determination Made That Rosemount Model 1152 Pressure Transmitters,Which Actuate Containment Vacuum Relief Valves FCV-25-7 & FCV-25-8,may Be Defective.Cause Not Stated.Transmitters Will Be Replaced
1998-05-26
[Table view]
Category:TEXT-SAFETY REPORT
MONTHYEARML17241A4891999-10-0707 October 1999
LER 99-004-00:on 990912,noted That MSSV Surveillance Was Outside of TS Requirements.Caused by Setpoint Drift.Subject MSSVs Are Being Refurbished & Retested Prior to Unit Startup from SL1-16 Refueling Outage.With 991007 Ltr
ML17241A4951999-09-30030 September 1999
Monthly Operating Repts for Sept 1999 for St Lucie,Units 1 & 2.With 991014 Ltr
ML17241A4741999-08-31031 August 1999
Rev 1 to PCM 99016, St Lucie Unit 1,Cycle 16 Colr.
ML17241A4591999-08-31031 August 1999
Monthly Operating Repts for Aug 1999 for St Lucie,Units 1 & 2.With 990913 Ltr
ML17241A4301999-07-31031 July 1999
Monthly Operating Repts for Jul 1999 for St Lucie Units 1 & 2.With 990805 Ltr
ML17241A4111999-07-16016 July 1999
LER 99-007-00:on 990610,unplanned Cooldown Transient Occurred Due to Personnel Error.Trained & Briefed Personnel & Revised Procedures.With 990716 Ltr
ML17241A4031999-07-0606 July 1999
LER 99-006-00:on 990605,sub-critical Reactor Trip Occurred Due to Inadvertent MSIV Opening.Caused by Personnel Error. Provided Operation Supervision Instruction to Operating Crews,Stand Down Meetings & Operator Aids.With 990706 Ltr
ML17241A4041999-07-0606 July 1999
LER 99-005-00:on 990604,CEA Drop Resulted in Manual Reactor Trip.Caused by Procedural Inadequacies.Procedure Changes Are Planned to Correct Lack of Procedural Guidance for CEA Subgroup Power Switch Replacement.With 990706 Ltr
ML17241A4091999-06-30030 June 1999
Monthly Operating Repts for June 1999 for St Lucie,Units 1 & 2.With 990712 Ltr
ML17241A3941999-06-30030 June 1999
LER 99-004-01:on 990415,as Found Cycle 10 Psv Setpoints Were Outside TS Limits.Caused by Manufacturing Process Defect. All Three Psvs Were Replaced with pre-tested Valves During Cycle 11 Refueling Outage.With 990630 Ltr
ML17355A3681999-06-30030 June 1999
Revised Update to Topical QA Rept, Dtd June 1999
ML17241A3551999-06-0404 June 1999
LER 99-002-00:on 990505,both Trains of Safety Injection Actuation Were Blocked During Surveillance.Caused by Procedure Error.Procedure Revised.With 990604 Ltr
ML17241A3631999-05-31031 May 1999
Monthly Operating Repts for May 1999 for St Lucie Units 1 & 2.With 990610 Ltr
ML17241A3321999-05-17017 May 1999
LER 99-004-00:on 990415,determined That as Found Cycle 10 Psv Setpoints Outside TS Limits.Root Cause Under Investigation.Psvs Replaced with pe-tested Valves During Cycle 11
ML17241A3271999-05-0606 May 1999
LER 99-003-00:on 990406,ECCS Suction Header Leak Resulted in Both ECCS Trains Being Inoperable & Entry Into TS 3.0.3. Caused by Chloride Induced OD Stress Corrosion Cracking of Piping.Made Code Repairs & Coated Piping.With 990506 Ltr
ML17241A3331999-04-30030 April 1999
Monthly Operating Rept for Apr 1999 for St Lucie,Units 1 & 2.With 990517 Ltr
ML17229B0801999-04-0707 April 1999
LER 99-002-00:on 990311,SG ECT Error Caused Operation with Condition Prohibited by Ts.Caused by Deficiencies in Data Analysis Guideline Instructions.Licensee Will Change Data Analysis Guidelines for Lead Analysts.With 990407 Ltr
ML17229B0841999-04-0707 April 1999
Rev 2 to PSL-ENG-SEMS-98-102, Engineering Evaluation of ECCS Suction Lines.
ML17229B0791999-04-0707 April 1999
LER 99-001-00:on 990309,discovered Inadequate Design & IST SRs for Iodine Removal Sys (Irs).Caused by Original Design Inadequacies & Personnel Error.Naoh Tank Vent Valve V07233 Was Tagged Open.With 990407 Ltr
ML17229B0961999-03-31031 March 1999
Monthly Operating Repts for Mar 1999 for St Lucie,Units 1 & 2.With 990408 Ltr
ML17229B0541999-03-10010 March 1999
LER 99-001-00:on 990211,inadequate TS SRs for SIT & SDC Isolation Valves Were Noted.Caused by Failure to Correctly Implement TS Srs.Submitted LAR to Align Required TS SR with Design Bases Requirements Being Verified.With 990310 Ltr
ML17229B0461999-02-28028 February 1999
Monthly Operating Repts for Feb 1999 for St Lucie,Units 1 & 2.With 990310 Ltr
ML17229B0051999-01-31031 January 1999
Monthly Operating Repts for Jan 1999 for St Lucie,Units 1 & 2.With 990211 Ltr
ML17229A9901999-01-20020 January 1999
LER 98-009-00:on 981223,noted That Facility Operated Outside of Design Basis.Caused by non-conservative MSLB Analysis Inputs.Will Review SR Component Differences Between Units & Will re-baseline LTOP Analysis.With 990120 Ltr
ML17229A9961999-01-14014 January 1999
SG Tube Inservice Insp Special Rept.
ML17229A9821999-01-0404 January 1999
LER 98-010-00:on 981207,RCS Boron Sample Frequency Required by Ts,Was Exceeded by Twelve Minutes.Caused by Personnel Error.Equipment Clearance Order Was Lifted to Draw Required Sample & Operations Procedure Was Changed.With 990104 Ltr
ML17229A9831998-12-31031 December 1998
Monthly Operating Repts for Dec 1998 for St Lucie,Units 1 & 2.With 990111 Ltr
ML17229A9611998-12-22022 December 1998
LER 97-002-01:on 981204,containment Sump Debris Screen Was Not IAW Design.Caused by Inadequate C/As for Sump Screen Anamolies.All Identified Sump Screen Deficiencies Were Dispositioned &/Or Repaired.With 981222 Ltr
ML17229A9561998-12-15015 December 1998
LER 98-008-00:on 981118,missed TS SG U Tube Insp.Caused by Encoding Errors While Using Remote Positioning Fixtures.All SG Tube Surveyed.With 981215 Ltr
ML17241A3581998-12-0909 December 1998
Changes,Tests & Experiments Made as Allowed by 10CFR50.59 for Period of 970526-981209.
ML17229A9421998-11-30030 November 1998
Monthly Operating Repts for Nov 1998 for St Lucie,Units 1 & 2.With 981215 Ltr
ML17229A9301998-11-25025 November 1998
LER 98-005-01:on 980807,discovered That New MOV Methodology Caused Past PORV Block Valve Operability Problem.Caused by Inadequacies in Original Vendor MOV Methodology.Planned Valve Mods Will Be Implemented During Cycle 11 1998 Outage
ML17229A9021998-11-0404 November 1998
LER 98-008-00:on 981008,inadequate Reactor Protection Sys Trip Bypass TS Was Noted.Caused by Poorly Worded Ts. Submitted LAR to Clarify Power Requirements for High Rate of Power Trips.With 981104 Ltr
ML17241A4931998-11-0101 November 1998
Statement of Account for Period of 981101-990930 for Suntrust Bank,As Trustee for Florida Municipal Power Agency Nuclear Decommissioning Trust (St Lucie Project).
ML17229A9051998-10-31031 October 1998
Monthly Operating Repts for Oct 1998 for St Lucie,Units 1 & 2.With 981110 Ltr
ML17229A8871998-10-19019 October 1998
Part 21 Rept Re Potential Defect in Swagelok Stainless Steel Front Ferrule,Part Number SS-503-1 Which Was Machined with Improper Length.C/A Includes Insp Equipment That Will 100% Identify Short Length
ML17229A8781998-10-19019 October 1998
Part 21 Rept Re Potential Defect in Swagelok Stainless Steel Front Ferrule,Part Number SS-503-1,which Was Machined with Improper Length.Insp Equipment That Will 100% Identify Short Length
ML17229A8771998-10-14014 October 1998
LER 98-006-00:on 980918,inadvertent Afas Actuation Was Noted.Caused by Degradation of Multiple Afas Power Supplies. Replaced Afas Power Supplies & Revised Procedures.With 981014 Ltr
ML17229A8761998-10-14014 October 1998
LER 98-007-00:on 980918,identified Discrepancies Between Fire Protection Design Requirements & Field Conditions. Caused by Inadequate Translation & Implementation of Fire Protection Requirements.Procedures Revised.With 981014 Ltr
ML17229A8721998-09-30030 September 1998
Monthly Operating Repts for Sept 1998 for St Lucie Units 1 & 2.With 981009 Ltr
ML17229A8511998-09-0202 September 1998
LER 98-005-00:on 980807,discovered That PORV Margins Were Insufficient to Accommodate Addl Conservatism.Caused by Inadequacies in Original Vendor MOV Methodology.Will Implement Planned Valve Actuator mods.W/980902 Ltr
ML17229A8611998-08-31031 August 1998
Monthly Operating Repts for Aug 1998 for St Lucie,Units 1 & 2.With 980911 Ltr
ML18066A2771998-08-13013 August 1998
Part 21 Rept Re Deficiency in CE Current Screening Methodology for Determining Limiting Fuel Assembly for Detailed PWR thermal-hydraulic Sa.Evaluations Were Performed for Affected Plants to Determine Effect of Deficiency
ML17229A8481998-08-0707 August 1998
Rev 1 to PSL-ENG-SEFJ-98-013, St Lucie Unit 2,Cycle 10 Colr.
ML17229A9461998-08-0707 August 1998
Rev 0 to PCM 98016, St Lucie Unit 2,Cycle 11 Colr.
ML17229A8301998-07-31031 July 1998
Monthly Operating Repts for July 1998 for St Lucie,Units 1 & 2.W/980814 Ltr
ML17229A8201998-07-29029 July 1998
LER 98-007-00:on 980630,inadequate Procedure May Have Resulted in SBO Recovery Complications.Caused by Inadequate Procedures.Attached Caution Tags to Appropriate Control switches.W/980729 Ltr
ML17229A7981998-06-30030 June 1998
Monthly Operating Repts for June 1998 for St Lucie,Units 1 & 2.W/980713 Ltr
ML17229A7701998-05-31031 May 1998
Monthly Operating Repts for May 1998 for St Lucie,Units 1 & 2.W/980612 Ltr
ML17229A7411998-05-28028 May 1998
LER 98-004-00:on 980430,discovered Waste Gas Decay Tank Operation W/O Available Oxygen Analyzers,Which Is Prohibited by Ts.Caused by Inadequate Licensee Review of License Amend. Oxygen Analyzer recalibrated.W/980528 Ltr
1999-09-30
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ACCELERATED Dl/RIBUTION DEMONSTRATION SYSTEM REGULATORY INFORMATION DISTRI BUTION SYSTEM ( RI DS )
ACCESSION NBR:9205010133 DOC.DATE: 92/04/24 NOTARIZED: NO DOCKET FACIL:50-389 St. Lucie Plant, Unit 2, Florida Power & Light Co. 05000389 AUTH. NAME . AUTHOR AFFILIATION SAGER,D.A. Florida Power & Light Co.
RECIP.NAME RECIPIENT AFFILIATION
- Document Control Branch (Document Control Desk)
SUBJECT:
In-House Event Rept 92-023:on 920421,turbine generator failed to trip during manual reactor trip. Root cause analysis still in progress. Solenoid valves removed & sent to independent lab for analysis.
.DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR I ENCL TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.
NOTES:
l SIZE:
RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL D PD2-2 LA 1 1 PD2-2 PD 1 1 NORRIS,J 1 1 D INTERNAL: ACNW AEOD/DOA 2,
1 2
1 ACRS AEOD/DSP/TPAB 2
1 2
1 AEOD/ROAB/DSP 2 2 NRR/DET/EMEB 7E 1 1 NRR/DLPQ/LHFB10 1 1 NRR/DLPQ/LPEB10 1 1 NRR/DOEA/OEAB 1 ". '1 NRR/DREP/PRPB11 2 2 NRR/DST/SELB 8D 1 1, NRR/DST/SICB8H3 1 1
~/~S.T PLB8D1 1 1 NRR/DST/SRXB 8E 1 ' 1 REG FILE 02 1 1 RES/DSIR/EIB 1 FILE 01 1 1 EXTERNAL: EG&G BRYCE,J.H 3 3 L ST LOBBY WARD "1 1 NRC PDR 1 1 NSIC MURPHY,G.A 1 1 NSIC POORE,W. 1 1 NUDOCS FULL TXT 1 1 D
D D
NOTE TO ALL "RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE iVASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!
TOTAL NUMBER OF COPIES REQUIRED: LTTR 32 ENCL 32
P.O. Box 128, Ft. Pierce, FL 34954.0128 g g I 4-8Q.
L-92-129 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555'E:
St. Lucie Unit 2 Docket No. 50-389 Event Date: April 21, 1992 Turbine Tri Failure Please find attached the preliminary internal problem report of our plant event which occurred on April 21, 1992. Pursuant to 10 CFR 50.73 a Licensed Event Report will be submitted within 30 days of the event date.
Please contact us if there are any questions about this submittal.
Very truly yours, Vice President St. Lucie Plant DAS/JJB/kw cc: Stewart D. Ebneter, Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, St. Lucie Plant DAS/PSL 4681-92 5'205010133 5'20424 PDR ADOCK 05000385' PDR an FPL Group company
ST. LUCIE PLANT IN HOUSE EVENT REPORT 92-023 TURBINE GENERATOR FAILED TO TRIP FOLLOWING MANUALREACTOR TRIP UNIT: 2 DATE: APRIL 21, 1992 I. INITIALPLANT CONDITIONS On April 21, 1992, St. Lucie Unit 2 was shutting down for a scheduled refueling outage.
Reactor power was at approximately 12%.
II. EVENT DESCRIPTION A scheduled Reactor-Turbine shutdown was in progress on Unit 2. During the shutdown, power moved to the top of the core as expected. Existing procedural guidance on Axial Shape Index (ASI) was being employed to minimize its affects.
When three out of four Local Power Density Pre-Trips on thc Reactor Protection
.System came in, the Nuclear Plant Supervisor (NPS) instructed the Reactor Control Operators to manually trip the Unit. A manual reactor trip was initiated, but the turbine did not trip. Several attempts were made to trip the turbine using the Turbine Trip push button with no success and thc Nuclear Watch Engineer tripped the turbine from the front standard.
II I. EVENT SEQUENCE St. Lucie Unit 2 was performing a scheduled reactor shutdown for refueling purposes. During the plant shutdown ASI approached its upper (negative) limit.
Coordination at controlling ASI within limits and maintaining reactor coolant temperature due to Xenon building in became more difficult. When reactor power was decreased to about 12%, control rod insertion had no effect on making ASI less negative and three of the four Reactor Protection System Local Power Density pre-trips came in. At this point, the NPS instructed the Reactor Control Operators to manually trip the unit and the manual reactor trip pushbuttons on RTGB (Reactor Turbine Guage Board) 204 and RTGB 201 were depressed at 0238 with the turbine trip pushbutton on RTGB 201 being depressed approximately two seconds later; however, the turbine did not trip. Standard Post Trip Actions from Emergency Operating Procedure (EOP) 1 were implemented.
When the turbine trip pushbutton was depressed, thc Governor Valves indicated closed but the Throttle Valves, Reheat Valves, and Intercept Valves indicated open.
Auto Stop Oil and the Emergency Trip Header indicated pressures of approximately 100 psi and 2000 psi, respectively. The megawatt recorder indicated ninety megawatts. Several morc attempts were made to trip the turbine using the pushbutton, but they were unsuccessful. At this point, the Reactor Control Operator opened the Generator output Breakers 8W52 and 8W49, secured the voltage regulator, stopped the Digital Electrohydraulic (DEH) pumps, closed the Main Stcam Isolation Valves (MSIV), and broke condenser vacuum.
IHE¹92-023, 4-24-92 SHEET 1 OF 3
III. EVENT SEQUENCE (cont'd)
The Assistant Nuclear Plant Supervisor instructed the Nuclear Watch Engineer to trip the turbine from the Front Standard. At 0241 all the turbine valves closed.
EOP-2, Reactor Trip Recovery, was then completed wi'th two sets of satisfactory Safety Status Checks, the plant was stabilized, and the Turbine Shutdown Procedure'as
'unction re-entered.
IV. EVENT EVALUATION A) PLANT RESPONSE The plant response to this event was as expected with the exception of the failure of the turbine to trip. Upon the reactor trip signal, the four Control Element Drive Mechanism (CEDM) Bus undervoltage relays should de-energize. This should energize (open) the 20 ET solenoid valve and drain the electro-hydraulic fluid from the emergency trip header ( Sec attachment ¹I). The 20 AST trip solenoid coil should simultaneously energize, pull down the mechanical trip lever, and dump the auto stop oil header. Decreasing auto stop oil pressure allows the Interface valve to open and dump the electo-hydraulic fluid emergency trip header. When auto stop oil pressure decreases to 45 psi, pressure switches 63-1 AST and 63-2 AST should lock in, actuating a generator primary lockout which trips the generator output breakers.
The same result should be obtained when attempting to trip the turbine via the Turbine Trip Pushbutton. A multi-discipline team is investigating to determine why the turbine failed to trip when the trip signals were initiated.
B) SAFETY SIGNIFICANCE The plant response to this event is bounded by section 15.1.5 of the PSL Unit 2 Final Safety Analysis Report (FSAR), "Increased Heat Removal by the Secondary System"as further described below..
12% Power Trip, No Operator Action Scenario.
MSIV's auto close at 600 psig. Cooldown terminated.
Core decay heat released via Main Steam Safety Valves (MSSV)
Cooldown rate bounded by limiting FSAR cooldown event.
100% Power Trip, No Operator Action Scenario.
Possible Safety Injection Actuation-Signal (SIAS) but no actual injection.
Automatic MSIV closure after 66 seconds.
Fuels RETRAN analysis validates that no core damage will occur.
100% Power Trip with multiple FSAR Chapter 15 Accident Scenario.
Operators trained on the simulator for multiple failure events beyond design basis.
Excess stcam demand events are simulated and procedurally addressed by the EOP's.
IHE¹92-023, 4-24-92 SHEET 2 OF 3
IV. EVENT EVALUATION(cont'd)
C) ROOT CAUSEANALYSIS A multi-discipline Turbine Investigation Team is performing a root cause analysis of this event. A Letter of Instruction, 2-LOI-T-67, "Evaluation of Turbine Solenoid Trip Function," was written to evaluate the operation of the turbine manual and automatic trip functions. Deficiencies identified are noted below. Root cause analysis is still in progress.
D) DEFICIENCIES IDENTIFIED Testing of thc 20 ET Trip solenoid, 20 AST solenoid valve, and the 20 OPC 1 and 2 solenoid valves was performed in accordance with 2-LOI-T-67. The results of this evaluation are as follows:
- 1) 20 ET Solenoid valve Thc original solenoid valve was removed to prescrvc the "as found" condition of the valve. A new solenoid valve was installed and tested satisfactorily. This verified the 20 ET electrical circuits did not contribute to the failures.
- 2) 20 AST Trip Solenoid The solenoid was tested numerous times with two of thc tests indicative of intermittent circuit problems. A loose connection was found on relay 62 ASTX / pin 6. This connection is in the circuit for all 20 AST trip functions.
Further troubleshooting is continuing.
- 3) 20 OPC 1 and 2 Solenoid Valves One OPC soleniod valve was removed prior to testing for potential failure mode analysis. Testing of one original and onc replacement OPC solenoid valve indicated acceptable operation of the OPC circuits.
V. CORRECTIVE ACTIONS
- 1. The original 20 ET, 20 OPC-1 and 20 OPC-2 Solenoid valves have been removed and were sent to an independent laboratory for analysis.
- 2. Maintenance is continuing to investigate thc root cause of the intermittent electrical problems of thc 20 AST Trip Solenoid. The circuits of the 20 ET and 20 OPC 1 and 2 Solenoids are also being evaluated to ensure similar problems do not exist.
- 3. Nuclear Fuels is evaluating additional guidance for ASI control at the end of core life.
- 4. Operations is evaluating additional guidance for EOP-1, "Standard Post Trip Actions", on actions to take for a reactor trip with no subsequent turbine trip.
IHE¹92-023, 4-24-92 SHEET 3 OF 3
e WESTINGHOUSE ELECTRO-HYDRAULIC CONTROL SYSTEM AND AUTO-STOP OIL SYSTEM EMERGENCY TRIPS
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- 2. GENERATOR OUTPUT BREAKERS OPEN ABOVE A PRESET POWER LEVEL
- 3. CHANGE IN GENERATOR OUTPUT AND TURBINE INLET PRESSURE
