ML17227A467

LER 92-004-00:on 920521,relay Time Delay Settings Altered Due to Personnel Error.Remaining Load Sequence Timers on Both Units 1 & 2 Were Inspected to Ensure Thumbwheel Switches Were Set correctly.W/920618 Ltr

ML17227A467
Person / Time
Site:	Saint Lucie
Issue date:	06/18/1992
From:	Sager D, Wachtel P FLORIDA POWER & LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
L-92-167, LER-92-004-02, LER-92-4-2, NUDOCS 9206250161
Download: ML17227A467 (7)

Text

DOCKET 05000335 ACCELERATED

'STIUBUTION DEMONSATION SYSTEM REGULAT Y INFORMATION DISTRIBUTION SYSTEM (RIDS)jag ACCESSION NBR:9206250161 DOC.DATE: 92/06/18 NOTARIZED:

NO FACIL:50-335 St.Lucie Plant, Unit 1, Florida Power&Light Co.AUTH.NAME AUTHOR AFFILIAT10N WACHT'EL,P.K.

Florida Power&Light Co.SAGER,D.A.

Florida Power&Light Co.RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER 92-004-00:on 920521,relay time delay settings altered due to personnel error.Remaining load sequence timers on both Unit 1&Unit 2 were inspected to ensure thumbwheel switches were set correctly.W/920618 ltr.DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR r ENCL g SIZE: TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.NOTES: RECIPIENT ID CODE/NAME PD2-2 LA NORRIS,J 1NTERNAL: ACNW AEOD/DOA AEOD/ROAB/DSP NRR/DLPQ/LHFB10 NRR/DOEA/OEAB NRR/DST/SELB 8D NRRfDSSPLB8D1 REG FILE 02 R LE 01 EXTERNAL: EG&G BRYCE i J.H NRC PDR NSIC POORETW.COPIES LTTR ENCL 1 1 1 1 2 2 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 3 3 1 1 1 1 RECIPIENT ID CODE/NAME PD2-2 PD ACRS AEOD/DSP/TPAB NRR/DET/EMEB 7E NRR/DLPQ/LPEB10 NRR/DREP/PRPB11 NRR/DST/SICB8H3 NRR/DST/SRXB 8E RES/DSIR/EIB L ST LOBBY WARD NSIC MURPHY,G.A NUDOCS FULL TXT COPIES LTTR ENCL 1 1 2 2 1 1 1 1 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 NOTE TO ALL"RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE!CONTACI'HE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT.20079)TO ELIMINATE YOUR NAME FROM DISTRIBUTION LINIS FOR DOCUMENTS YOU DON'T NEED!FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 32 ENCL 32 P.O.Box 128, Ft.Pierce, FL 34954-0128 June 18, 1992 L-92-167 10 CFR 50.73 U.S.Nuclear Regulatory Commission Attn: Document Control Desk washington, D.C.20555 Re: St.Lucie Unit 1 Docket No.50-335 Reportable Event: 92-004 Date of Event: May 21, 1992 Relay Time Delay Settings Altered due to Personnel Error causes Condition Prohibited b Technical S ecifications The attached Licensee Event Report is being submitted pursuant to the requirements of 10 CFR 50.73 to provide notification of the subject event.Very truly yours, D.A.ger Vice r sident St.Lu e Plant DAS/JWH/kw Attachment cc: Stewart D.Ebneter, Regional Administrator, USNRC Region II Senior Resident Inspector, USNRC, St.Lucie Plant DAS/PSL N715-92 9206250161 920618 PDR ADOCK 05000335 8 PDR an FPL Group company FPL FcccirrTlc d IFIC Form 380 US.NUCLEAR REGNATORY COMMISSION LICENSEE EVENT REPORT (LER)ATTIXXCOCACIICX 0IICCI01 00CCCC 00000 CCICIATTO OACCC IOI ImCCXCC TO 00XCTT TCOI~0CTXCIATXCI IXXIT CT0XI ICXACCT: 000 ICTA TOCCAIXI CCICCXIC ICCAICCXI IAACXII ICICIAIC lo llo ICCIXTXI AICI ICTCCIC INAIXTCNf ITMCIXI+44QL IIX IAAXC AC IC OAAT0XIT CASSAVA WIS44lRW, OC 00MC rCD lo THC 00tIICCX00 ICOUCTXXI ICOCCT 0IICCICC.CIIICI OI IWNODCIC IIXI IMXXT AOCXCIXA OC 00001 FACILITY NAME (1)St.Lucie Unit 1 DOCKET NUMBER (2)PAGE 3 050003351 0 4~(4)Relay Time Delay Settings Altered due to Personnel Error Causes Condition Prohibited by Plant Technical Specifications EVENT DATE (5)LER NUMBER (6)REPORT DATE m OTHER FACILITIES INVOLVED (8)0 5 DAY 21 YEAR 9 2 S AL R 9 2 0 0 4 0 0 0 6 DAY YEAR 1 8 9 2 FACILITY NAMES N/A N/A DOCKET NUMBER(S)05000 OPERATING MODE (9)20.402(b)20.405(c)50.73(a)(2)(iv)

THIS REPORT IS SUBMITIED PURSUANTTOTHE REQUIREMENTS OF 10 CFR: Check one or more of the followin (11)73.71(b)POWER LEVEL (10)1 0 0 20.405(a)(1)(i) 20.405(a)(1)(ii)20.405(a)(1)(iii) 20.405(a)(1)(iv) 20.405(a)(1)(v) 50.36(c)(1) 50.36(c)(2) 50.73(a)(2)(I)50.73(a)(2)(ii) 50.73(a)(2)(iii) 50.73(a)(2)(v) 50.73(a)(2)(vii) 50.73(a)(2)(viii)(A) 50.73(a)(2)(viii)(B) 50.73(a)(2)(x) 73.71(c)OTHER (Specify in Abstract below andin Text NRC Form 388A)LICENSEE CONTACT FOR THIS LER 12 Patricia K.Wachtel, Shift Technical Advisor TELEP ONE NUMBER AREA CODE 4 0 7 465-3550 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 13 SYSTEM COMPONENT MANUFAC-REPORTABLE TURER TO NPRDS CAUSE SYSTEM COMPONENT MANUFAC-TURER REPORTABLE TO NPRDS SUPPLEMENTAL REPORT EXPECTED 14 YES (If yes, complete EXPECTED SUBMISSION DATE)NO EXPECTED MONTH DAY YEAR SUBMISSION DATE (15)ABSTRACT (Limit to 1400 spaces.I.e.approximately fifteen single-space typewritten lines)(1 6)On May 21, 1992, St.Lucie Unit 1 was in mode 1, operating at 100%steady state power.A utility engineer was inspecting the time delay settings on Agastat relays In specifh electrical buses when it was discovered that the timer thumbwheel settings for the 1A Component Cooling Water pump and the 18 Containment Spray pump were very dose to the+I-one second Technical Specificathn surveillance tolerance for diesel generator load sequencing.

Subsequent investigation revealed that the time delay settings had been altered.The cause of this event was personnel, error.While cleaning the cubides in whhh these relays were located, a contract maintenance worker inadvertently changed the time settings on the thumbwheel switches while cleaning the faces of the relays.Corrective actions taken include: 1)the Agastat relays were reset to comply with Technical Specifications, 2)the maintenance crews were counseled on how to clean the relays and not disturb the had sequence timer settings, 3)the switchgear cleaning procedure was changed to ensure the correct thumbwheel switch setting is verified prior to returning the electrical bus to service, and 4)the remaining had sequence timers on both Unit 1 and Unit 2 were inspected to ensure the thumbwheel switches were set correctly.

FPL Facsimile of NRC Form 366 (M9)

FPL Fffcaffffle Di AC FOffff$$IMol Ua.NUCLEAR REGULATORY COMMfssfON UCENSEE EVENT REPORT (LER)TEXT CONTINUATION ITTCTTTD CCCI ICL TINCI fl~AIICCT TCTCIATKD TAICIIN ICII ICWCtfN TO CCACCT TCTII TICI CCCICIATIIW CCIICCTII7I ICCIXCT: TOC IITA TCITWNCT CTACCNTC ICCNICNC TA/ITIN CCTCIAIC lO llC ICCNCC NCI ICTCSNC NINAINICNT CDANCE~IAC MX1CAR ICOAAICITT CNIICIIA WANDCITCN, DC TIINC AKI lO TIN tN TTIATÃTI CTACT11I IICICCT ff I ICCICC CITICC Cf IWWCINNT NCT IACIICT WAIADKflDA DC TCICA FACILITY NAME (1)St.Lucie Unit 1 DOCKET NUMBER (2)LER NUMBER (6)EQUENTIAL REVISIO NUMBER NUMBER PAGE (3)0500033592 TEXT (limore spaceis required, use additional NRC Form 366A's)(17)0 0 4 0 0 0 2 0 4 On May 21, 1992, St.Lucie Unit 1 was in mode 1 at 100%steady state power.A utility engineer was inspecting the 1A3 and 1B3 electrical buses (EIIS:EB)to check the time delay settings on specific Agastat relays.This inspection was being performed in response to an engineering assessment relating to recent industry events on load sequence timers.The investigation at St.Lucie Unit 1 revealed that the time delay settings for the 1A Component Cooling Water pump (EIIS:CG)(CGW)and the 1B Containment Spray pump (EIIS:BE)(CS)were Incorrect.

The following data was provkled following the inspection:

1ACCW 1B CS REQUIRED TIME AS-FOUND (4-1 second)Tl-IUMBWHEEL SETIING 6.00 7.01 12.00 1298 AS-FOUND TlME (05-2142)7.17 13.11 A%AFT TIME 6.12 secords 12.16 seconds This indicated that both the 1A CGW and 1B CS pumps had their time delay settings outskfe of the+/-one second load sequencing setting required by Technical Specification sutveillance requirement 4.8.1.1.2.e.11.

The times were last verified during the Unit 1 Periodic Integrated Test of the Engineered Safety Features performed in October, 1991.The following time settings were documented for these pumps: 1A CGW pump-6.18 seconds;1B CS pump-12.16 seconds.Each of these times was within the acceptable tolerance allowed by plant Technical Specifications.

The cause of this event has been attributed to personnel error.The inadvertent changing of the timer thumbwheel switches appears to have occurred when the cubfcies on the 4160 volt buses containing these relays were cleaned during the last Unit 1 refueling outage.When the busses were cleaned, the worker could come in contact with the thumbwheei and inadvertently alter the time delay settings.There were no unusual work conditions which may have contributed to this event nor was there any specific procedural gukfance to caution the contract maintenance personnel not to disturb the load sequence timer settings when cleaning the relays.This event is reportable under the requirements of 10CFR50.73.a.2.i.B as"any operation or condition prohibited by the plant Technical Spec Tiications." Technical Specification surveillance requirement 4.8.1.1.2.e.5 requires that once per eighteen months, a loss of off-site power in conjunction with an engineered safety feature actuation test signaI (EIIS:JE)be simulated.

Following the start of the emergency diesel generator (EDG)(EIIS:EK), the emergency busses with permanently connected loads energization and the auto~nnected emetgency (accident) loads energization through the auto-sequencer must be verified.Verification that the automatic load FPL Facsimiie of NRC Form 366 (649)

AIL Farmlrrf fo of IRC Fcrrrr 368 gHffrj U.S.NUCLEAR REGULATORY COMM fSS Ioff LICENSEE EVENT REPORT (LER)TEXT CONTTNUATTON AARTORo OWI RIL TIRCI Tl cTTORR ACAOT TCTTAATTO ILROTR IT IT ICIATTCR Td OCARLT TATll TIRI OCCICIATCR CCLIT OTIC TRIARCH: RA NTL ICRWART COWRRTC IRONCRAI IMTRR ICRRATC ld IIR ICOCICR RD ICICRTC RANI/R IR RT CRAROI rRRRL IIR ILCLTAR ICCRAATCRT OISRRRTL W RRATR7I.OC RRRL Ho Io TIR PARRRCIR lCITUCTCR IROCCT TTI IOCIRL CTRCC EÃAMRARTRRT RO RAXRT, WARRRROR OC TOOL FACILITY NAME (1)St.Lucie Unit1 DOCKET NUMBER (2)LER NUMBER (6)EQUENTIAL NUMBER REVISIO NUMBER PAGE (3)0 500 0335 TEXT (If more spaceis required, use additional NRC Form 366A's)(17)9 2 0 0 4 0 0 0 3 0 4 sequence timers are operable with the interval between each load bkck within+/-one second of its design interval is required as per Technical Specification surveillance requirement 4.8.1.1.2.e.11.

Although this surveillance was performed satisfactorily seven months ago during the Unit 1 refueling outage, the as-found settings for the 1A Component Cooling Water and the 1B Containment Spray pumps indicate that they would not have loaded onto the EDG in the proper sequence.A detailed engineering evaluation (JPN-PSL-SEEP-92-031) was perfomed to demonstrate that the EDG would have performed acceptably with the as-'found timer settings.Conclusions from this evaluation indicated that the timer settings did not adversely affect the ability of the Emergency Diesel Generators to supply power to the required Engineered Safety Feature loads under design basis loss of off-site power and accident conditions.

The health and safety of the public was not at risk at any time while in this condition.

1.The required time delay settings were restored for the two altered load sequence time+.2.The remaining load sequence timers onboth Unit1 and Unit 2 were inspected to ensure the thumbwheel switches were set correctly.

All were unchanged.

3.Electrical maintenance will visually verify that all load sequence timers are set correctly prior to entering Mode 4 subsequent to a refueling outage.This verification will be incorporated into plant procedures.

4.The switchgear cleaning procedure was changed to include steps to verify the timer thumbwheel switch setting is within Technical Specifications limits before releasing the bus for soNice.5.Electrical maintenance supervisors counseled contractor and utility maintenance personnel not to disturb the load sequence timers while cleaning the switchgear cubicles.6.The Plant Maintenance Departments evaluated other preventative maintenance cleaning procedures for the potential to disturb the settings of load sequence timers.FPL Facsimile of NRC Form 366 (649)

FPL Fscttmle at PIC Foml SOB IMQj U.S.NUCLEAR REGULATORY COMM SS TON LICENSEE EVENT REPORT (LER)TEXT CONTINUATION I¹IWOIOO t¹e IOI TI WOI OI COTWATI¹J¹IC¹OCII I¹OKN¹TO OOWLTTOTII ll¹I OOCCCCAlla¹ Ot1ICOODI I¹cl¹oo¹I>II¹c Tawwtccl oC¹o¹¹l1 I¹olc¹two¹Jsol Ioo¹AI¹lo llc I¹cccoo HCI I¹¹C¹T1¹AHAI¹I¹IIT OIIA¹CH t¹CCOL II¹IA¹CCA¹l¹C¹CATI¹II COO+O¹t¹C AAOIOICW.OO TIOOA IID TO TIO T JIUC¹WOIW ICCCCICH IIOC¹OT CII WAIL%OIIICO I¹¹AKIÃA¹¹T NO¹AX¹T.WA¹¹et¹t¹C OO$0¹CL FACILUY NAME (1)St.Lucie Unit 1 DOCKET NUMBER (2)LER NUMBER (6)EQUENTIAL REVISIO NUMBER.NUMBER PAGE (3)0 500 0335 9 2 TEXT (If more spaceis required, use additional NRC Form 366A's)(17)0 0 4 0 0 0 4 0 4 There was no component failure during this event;however, specific component identification is included for informational purposes.Relay: Part Number.Manufacturer:

Agastat 7tming Relay DSB XXO I 25SPAXAA Amerace Corporation There have been no previous events in which maintenance personnel have inadvertently altered relay time delay settings.FPL Facsimile of NRC Form 366 (649)