ML18009A759

LER 90-024-00:on 901121,64 Bussman Fnm Type Fuses in 125- Volt safety-related Applications Found Unacceptable.Caused by Recent Downgrade in Fuse Performance Specs Provided by Vendor.Fuses Replaced,Per Plant Mod PCR-5549.W/901221 Ltr

ML18009A759
Person / Time
Site:	Harris
Issue date:	12/21/1990
From:	Richey R, Verrilli M CAROLINA POWER & LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
HO-900207-(O), LER-90-024, LER-90-24, NUDOCS 9012260299
Download: ML18009A759 (6)

Text

REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9012260299 DOC.DATE: 90/12/21 NOTARIZED: NO DOCKET g FACIL:50-400 Shearon Harris Nuclear Power Plant, Unit 1, Carolina 05000400 AUTH. NAME AUTHOR AFFILIATION VERRILLI,M. Carolina Power & Light Co.

RICHEY,R.B. Carolina Power & Light; Co. R RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER 90-024-00:on 901121,64 Bussman FNM type fuses in 125-volt safety-related applications found unacceptable. Caused D by recent downgrade in fuse performance specs provided by vendor. Fuses replaced,per Plant Mod PCR-5549.W/901221 ltr.

DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR ( ENCL TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.

j SIZE:

NOTES:Application for permit renewal filed. 05000400 D

RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL D PD2-1 LA 1 1 PD2-1 PD 1 1 BECKER,D 1 1 INTERNAL: ACNW 2 2 ACRS 2 2 AEOD/DOA 1 1 AEOD/DSP/TPAB 1 1 AEOD/ROAB/DSP 2 2 NRR/DET/ECMB 9H 1 1 NRR/DET/EMEB 7E 1 1 NRR/DLPQ/LHFB11 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/SICB 7E 1 1 PLB8D1 1 1 NRR/DST/SRXB 8E 1 1 REG F 02 1 1 RES/DSIR/EIB 1 1 RGN2 LE 01 1 1 EXTERNAL: EG &G BRYCE, J. H 3 3 L ST LOBBY WARD 1 1 NRC PDR 1 1 NSIC MAYS;G 1 1 NSIC MURPHY,G.A 1 1 NUDOCS FULL TXT 1 1.

D S,

D NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE iVASTE! CONTACT THE DOCUMENT CONTROL DESK, ROON! P 1-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUKIENTS YOU DON'T NEED!

FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 33 ENCL 33

Carolina Power 8 Light Company P, O. Box 165 ~ New Hill, N. C. 27562 OEC 2 i >990~

R. B, RICHEY Vice President Harris Nuclear Projecl Letter Number.'HO-900207 (0)

U.S. Nuclear Regulatory Commission ATTN: NRC Document Control Desk Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 DOCKET NO. 50-400 LICENSE NO. NPF-63 LICENSEE EVENT REPORT 90-024-00 Gentlemen.'n accordance with Title 10 to the Code of Federal Regulations, the enclosed Licensee Event Report is submitted. This report fulfills the requirement for a written report within thirty (30) days of a reportable occurrence and is in accordance with the format set forth in NUREG-1022, September 1983.

Very truly yours, R. B. Richey Vice President Harris Nuclear Project RBR:gcm Enclosure cc: Mr,. R. A. Becker (NRR)

Mr. S. D. Ebneter (NRC RII)

Mr. J. E. Tedrow (NRC SHNPP) 90122b0299 90122l PEIR ADOCK 0 000400 S PDR MEMr LER"90-024/'/OSl

NRC FOAM 366 U.S, NUCLEAR REGULATORY COMMISSION

($ 69) APPROVED QMB NQ. 31504104 EXPIRES: 4I30/92 ESTIMATED BURDEN PER AESPONSE TQ COMPLY WTH THIS INFORMATION COLLECTION REQUEST: 50.0 HRS. FORWARD LICENSEE EVENT REPORT ILER) COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS AND REPORTS MANAGEMENT BRANCH IP630), U.S. NUCLEAR REGULATORY COMMISSION. WASHINGTON. DC 20655, AND TO THE PAPERWORK REDUCTION PROJECT (31600'loe), OFFICE QF MANAGEMENTANO BUDGET, WASHINGTON, DC 20503.

FACILITY NAME (11 DOCKET NUMBER (1) PA E I Shearon TITLE (el Harris Nuclear Plant Unit /f1 o 5 o o o40 i Ov03 Inadequate Fuses Used in Safety Related 125 volt D.C. Applications EVENT DATE ISI LER NUMBER (6) REPORT DATE (7I OTHER FACILITIES INVOLVED IS)

MONTH OAY YEAR YEAR SEQUENTIAL MONTH OAY YEAR FACILITYNAMES DOCKET NUMBER(S)

NUMBER l(((: NUMbER 0 5 0 0 0 2 1 9 0 9 0 0 2 4 00 12 2 190 0 5 0 0 0 THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR (): IChech one or more ot the Ioiiovrinp) 01)

OPERATING MODE (bl 20.40216) 20.405(c) 50.73(e I (2)(iv) 73.7)(b)

POWER 20.406( ~ l(1) (ll 50.3$ (cl I (I 50.7 3(e I (2)(el 73.71(cl LEYEL (I 0 I 9 4 20.405 (4 ) 11) (il) 60.3$ (c)12) 50.73(sl(2)(vill OTHER ISpectty rn Abrtiect Oelovvend In Feet, HIIC Foim vvg+yi 20.4054) II) (ilil 50.73( ~ I(2) lli 60.73(el(2)(vilB(AI 366AI 10 405(s I (I I l iv) 60.73( ~ )12)liil 50.73(sl(2((vill) IBI

((P(fvfci v2(47. " 20 405(el(l )Nl 60,73(e)11)(iiB 60,73(s(12)(el LICENSEE CONTACT FOR THIS LER (12)

NAME TELEPHONE NUMBER Michael Verrilli Regulatory Compliance AREA CODE 919 362 -2 03 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 113)

CAUSE SYSTEM COMPONENT MANVFAC REPORTABLE MANVFAC EPQRTABLE CAUSE SYSTEM COMPONENT

'TURER TQ NPRDS g!I@i@In(i TVRER TO NPRDS K)))%4 gjj(jkj SUPPLEMENTAL REPORT EXPECTED (14) MONTH OAY YEAR EXPECTED SUBMISSION DATE (15I YES III yeL comPiete EXPECTED SU64IISSIDII DATFI NO ABSTRACT ILimit to tc00 rpecet, i,e., epproeimereiy Iifteen rinpie rpece typeviiirten linn) 115)

On October 23, 1990 the plant was operating in Mode 1 at 94X power. A Plant Change Request (PCR) was submitted to perform an engineering eval'uation on the acceptability of certain fuses used in 125 volt and 250 volt safety related and non-safety related DC circuits. This was a result of information received from a Nuclear Network Operating Experience Entry (80E-3990). This evaluation which incl()ded communication with Bussman Incep applicable fuse vendor, resulted in the determination that sixty-four (64) Bussman FNM type fuses that were originally acceptable for use in 125 volt safety related applications were now judged unacceptable and would need to be replaced. This is due to the possibility that the fuses could fail to clear (blow) as required due to the establishment of an arc across the molten ionized fuse element. The Significant Operational Occurrence Report (SOOR) which had been generated as a result of the 'CR was subsequently evaluated to be reportable to the NRC. The cause of this event can be attributed to the recent downgrade in fuse performance'pecifications provided by the vendor for the FNM type fuses used in these particular DC applications.

At the 'time of design and construction of the Harris plant, adequate documentation was provided by fuse vendors to justify fuse performance in their respective applications, whether in either AC or DC circuits. There has recently been industry wide changes in information provided by 'vendors pertaining to fuse performance in DC appl.ications. This concern resulted in OE-3990 and the subsequent evaluation at Harris. Corrective actions included the evaluation and replacement of the sixty-four (64) unacceptable Bussman FNM type fuses. There were no significant safety consequences as a result of this event. No failed fuses were identified during the replacement process and all applicable electrical components functioned normally as required.

NRC Form 36$ (5691

N RC FORM 368A U.S. NUCLEAR REGULATORY COMMISSION (64(91 APPROVED OMB NO. 31500104 EXPIRES.'/30/92 LICENSEE EVENT EPORT ILERI ESTIM~O BURDEN PER AESPONSE TO COMPLY WTH THIS INFOAMATION COLLECTION AEOUEST: 500 HRS, FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRANCH IP830I. U.S. NUCLEAR REGULATORY COMMISSION. WASHINGTON, OC 20555. AND TO 1ME PAPERWORK REDUCTION PROJECT (315041041, OFFICE OF MANAGEMENTAND BUDGET. WASHINGTON. DC 20503.

FACILITY NAME (11 DOCKET NUMBER (21 LEA NUMBER (61 PAGE (3I Shearon Harris Nuclear. Plant YEAR @P SSOUENTIAL NUMbER $1 'P RSVISION NUMbbR Unit //1 o s 0 o o4 00 .90 02 4 0 0 02 oF 0 3 TEXT ///mab bpbCo U mboirbd, ubb bddrtioob//VRC Form 3864'4/ IITI EVENT DESCRIPTION:

On October 23, 1990 the plant was operating in Mode 1 at 94X power. PCR-5549 was initiated to perform an engineering evaluation on the adequacy of fuses in certain safety and non-safety circuits. This evaluation was performed to determine the applicability of Nuclear Network Operating Experience Entry 40E-3990. Per plant procedure AP-600 (Plant Change Request Initiation), when reportability is uncertain, a SOOR must be submitted. This was 'performed on October 23, 1990. The engineering evaluation, which was being performed by Nuclear Engineering Department (NED) personnel, included conversations with one of the applicable fuse vendors, Gould-Shawmut Inc. Per these conversations and other aspects of the evaluation, there was thought to be no problem at the plant. This preliminary decision was brought to the attention of the Plant Nu'clear Safety Committee (PNSC) on November 21, 1990. During the ensuing discussion, the Technical Support group recommended contacting Bussman Inc., for additional fuse performance information. Communications with Bussman determined that sixty-four (64) Bussman Type FNM fuses used in 125 VDC safety related applications were not acceptable and would need to be replaced. The SOOR was then evaluated to be reportable to the NRC and Plant Modification 8PCR-5549 was initiated on November 23, 1990 to replace these fuses and evaluate/document the adequacy of the other fuses used in the 125 volt safety related DC system.

Replacement of the sixty-four (64) FNM type fuses was completed on November 25, 1990. The remaining fuses (approximately 650) were determined to be adequate for their applications based on either vendor supplied fuse performance data or previous PCR evaluations that included independent laboratory testing.

This event is being reported in accordance with 10CFR50.73 (a) (2) (ii) (B) as a condition that was outside the design basis of the plant.

CAUSEl The cause of this event can be attributed to the recent downgrade in fuse performance specifications provided by the vendor for the FNM type fuses used in these particular DC applications. At the time of design and construction of the Harris plant, adequate documentation was provided by fuse vendors to justify fuse performance in their respective applications, whether in either AC or DC circuits. There has recently been industry wide changes in information provided by vendors pertaining to fuse performance in DC applications. This concern resulted in OE-3990 and the subsequent evaluation at Harris.

N R C Fonb 386A (689)

Nr!C FORM 366A (649 I LICENSEE EVENT

'PPROVED U.S. NUCLEAR REGULATORY COMMISSION ORT (LER) INFOR OMB NO. 31500106 EXPIRES! 6/30(92 EST)M~BURDEN PER RESPONSE TO COMPLY WTH THIS N COLLECTION REOUEST: 500 HRS, FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRANCH IP.530). U.S. NUCLEAR REGULATORY COMMISSION. WASHINGTON, DC 20555. AND TO THE PAPERWORK REDUCTION PROJECT (31500)oi). OFFICE OF MANAGEMENTAND BUDGET, WASHINGTON. DC 20503.

FACILITY NAME (I ) DOCKET NUMBER (2) LER NUMBER LB) PAGE (3) mo) 56OUENT!AL REVISION Shearon Harris Nuclear Plant YEAR NUMBErl NUM65 II Unit f/1 o s o o o4 00 90 0 2 4 0 0 03 oFO 3 TEXT N moro rooro rr roOoworL oro oddro(roo( HRC Form 36649) ()71 SAFETY SIGNIFICANCE:

None of the fuses that were deemed unacceptable during this evaluation showed any signs of failure during the replacement process and al.l the applicable electrical components functioned normally as required. Therefore no significant safety consequences were present as a result of this event.

CORRECTIVE ACTIONS:

1. Sixty-four (64) Bussman type FNM fuses were replaced per Plant Modification PCR-5549 in the 125 voI.t DC Safety Related system.

I EISS CODE INPORMATION:

DC Power System Class 1E EJ NRC Form 366A (689)