ML18004B886

LER 87-011-01:on 870307,breaker Tripped Open Causing de-energization of Auxiliary Bus 1E.Caused by Procedural Inadequacy.Defective PIC Card in Power Supply to LT-112 Relay Replaced & Procedure revised.W/870722 Ltr

ML18004B886
Person / Time
Site:	Harris
Issue date:	07/22/1987
From:	Schwabenbauer, Watson R CAROLINA POWER & LIGHT CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
HO-870459-(O), LER-87-011, LER-87-11, NUDOCS 8707280188
Download: ML18004B886 (8)

Text

EGULA ORY INFORMATION DISTRIBUTl SYSTEM<BIDS)ACCESSION NBR: 8707280188 DOC.DATE: 87/07/22 NOTARIZED:

NO'OCKET 0 FACIL: 50-400 Shearon Harv is Nucleav Power Plantr Unit ii Carolina'5000400 AUTH.NAME AUTHOR AFFILIATION SCHWABENBAUER.

Carolina Power 8c Light Co.WATSON'.A.Carolina Power 5 Light Co.RECIP.NAME RECIPlENT AFFILIATION

SUBJECT:

LER 87-011-01:

on 870307'reakev tv ipped open causing de-energ ization of auxiliary bus 1E.Caused bg pv ocedural inadequacy.

Defective PIC card in powev'upply to LT-112 v clay v eplaced h pv ocedure revised.W/8 DISTRIBUTION CODE: IE22D COPIES RECEIVED: LTR I ENCL I SIZE: TITLE: 50.73 Licensee Event Repov t (LER)r Incident Rpti etc.NOTES: Application for permit renewal filed.05000400 RECIPIENT ID CODE/NAME PD2-1 LA BUCKLEY'S B COPIES , LTTR ENCL 1 1 1 RECIPIENT ID CODE/NAME PD2-1 PD COPIES LTTR ENCL 1 1 INTERNAL: ACRS MICHELSON AEOD/DOA AEOD/DSP/ROAB DEDRO NRR/DEST/*DS NRR/DEST/ELB NRR/DEST/MEB NRR/DEST/PSB NRR/DEST/SGB NRR/DLPQ/GAB NRR/DREP/RAB NRR/PMAS/ILRB~RE~QrRC 02 RES TELFDRDr J RQN2 FILE 01 EXTERNAL: EGSQ GROH>M LPDR NSIC HARRIS.J 1 1 1 1 2 2 1 1 1'0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 5 5 1 1 1 1 ACRS MOELLER AEOD/DSP/NAS AEOD/DSP/TPAB NRR/DEST/ADE NRR/DEST/CEB NRR/DEST/ICSB NRR/DEST/MTB NRR/DEST/RSB NRR/DLPG/HFB NRR/DOEA/EAB NRR/DREP/RPB NRR/PMAS/PTSB RES DEPY GI RES/DE/EIB H ST LOBBY WARD NRC PDR NSIC MAYST G 2 2 1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 1 1 2 2 1 1 1 1 1 1 1 1 1 1 TOTAL NUMBER OF COPIES REQUIRED: LTTR 45 ENCL 43

~~~0 NR>>Form 36F, (903)LICENSEE EVENT REPORT (LER)U.S.NUCLEAR REGULATORY COMMISSION APPROVED OMB NO.3)600104 EXPIRES: 5/31/SB FACILITY NAME (I)SHEARON HARRIS PLANT UNIT 1 TITLE (4)"6.9 KV ONSITE DISTRIBUTION" DOCKET NUMBER (2)o s o o o 4 0 PA E 3 1 OF 0 MONTH DAY YEAR EVENT DATE (5)YEAR LER NUMBER LBI SEQUENTIAL o NUMBER REPORT DATE (7)OAY YEAR MONTH NUMBER DOCKET NUMBER(3)0 5 0 0'0 FACILITY NAMES OTHER FACILITIES INVOLVED (5)03 07 8 7 8 7 0 1 1 0 1 7 2 2 8 7 0 5 0 0 0 OPERATING MODE (0)4 POWE R LEvEL 0 0>>>>O>>'y.T(>>N:~g,.~;.j, 60.73(e)(2)(lv)50,73(e)(2)(v) 60.73(e)(2)(vll)50,73(e)(2)(vill)(A)50.73(~)(2)(vill)(0)50.73(~)(2)(x)20.402(b)20.405(~)(1)(l)20.405(~)(I)(il)20.405(~)(1)(ill)20 A05(~)(I)(lv)20.406(~)(1)(v)20AOS(c)60.35 (e)(1)60.35(c)(2) 60.7 3(e)(2 I I I)50.73(e)(2)(il)60.73(e)(2)(lll)LICENSEE CONTACT FOR THIS I.ER (12I THls REPQRT Is sUBMITTED PURsUANT To THE REQUIREMENTs oF 10 cFR g: fcheck one or morr of thr folio~/no)(ll)73.71(5)73.71(c)QTHER (specify In Aortrrct herovvrnd In Trxt, IYRC form 366AI NAME R.SCHWABENBAUER

-REGULATORY COMPLIANCE TELEPHONE NUMBER AREA CODE 9 19 362-26 9 COMPLETE ONE LINE fOR EACH COMPONENT FAILURE OESCRIBEO IN THIS REPORT (13)CAUSE SYSTEM COMPONENT MANUFAC TVRER REPORTABLE TO NPRDS CAUSE rS.'.SYSTEM COMPONENT MANUFAC.TURER">>"N'PORTABL am TO NPRDS>>g.U J W 120 N~'4 g4&YP%4he!SUPPLEMENTAL REPORT EXPECTED (14)YES flf yer, complrre EXPECTED SVBhtISSIOIV DATEI NO ABSTRACT ILlmir ro tr00 rpeceL I.r., epproximerely fifrren rlnrrr rpere typenm'tron liner)(16)ABSTRACT EXPECTED SUBMISSION DATE 116)MONTH OAY YEAR On March 7, 1987, an Auxiliary Operator (AO)was performing a weekly surveillance test (OST-1023) which is for offsite power verification.

One of the requirements of the OST is to ensure the breaker release lever is in the neutral position with the breaker closed.When the AO checked Auxiliary Bus IE feeder breaker 121, the breaker was inadvertently tripped open causing the de-energization of Auxiliary Bus IE and Safety Bus 1B-SB.This occurred at 2230 hours0.0258 days <br />0.619 hours <br />0.00369 weeks <br />8.48515e-4 months <br /> on March 7, 1987.The de-energization of Bus 1B-SB caused the 1B-SB Diesel Generator to start and the actuation of Sequencer 1B-SB on Bus undervoltage.

The AO immediately closed the breaker cabinet and notified the Control Room of the incident.The Senior Control Operator (SCO)then initiated AOP-025 for the loss of one emergency bus and all plant systems were then returned to normal.At the time of the incident, the plant was in Mode 4 at 345'F.and 350 psig.There were no adverse'consequences.

due to this event and safety systems performed as required.To prevent recurrence, the applicable procedure has been revised.8707280188 870722 PDR ADOCK 05000400~8 NRC Form 366 (94I3)pn g (

NRC Form 388A (940 I LI NSEE ENT REPORT (LER)TEXT CONTINU ON U.S.NUCLEAR REGULATORY COMMISSION APPROVED OMB NO.3(50&104 EXPIRES: 8/31/88 FACILITY NAME (1)SHEARON HARRIS PLANT UNIT 1 OOCKET NUMBER (21 YEAR LER NUMBER (5)SEOUENTIAL NUMBER'.od REVISION NUMSER PAGE (3)TEXT//P/r>>rs<<>>cr/4 s///Irsd, I/rr dd/ddo>>///RC Fcrrn 38543/(17)o s o o o 400 8 7 011 0 1 0 2 OF 0 3 TEXT DESCRIPTION On March 7, 1987, an Auxiliary Operator (AO)was performing a weekly surveillance test OST-1023 entitled"OFFSITE POWER AVAILABILITY VERIFICATION WEEKLY INTERVAL MODES 1-2-3&4." One of the requirements of the OST is to ensure the breaker release lever is in the neutral position with the breaker closed.The AO did this by checking the release lever with his foot for freedom of movement.The AO had used this method without incident in the past.When the AO went to check the Auxiliary Bus 1E feeder breaker 121, the breaker tripped open causing the de-energization of Auxiliary Bus lE.This also de-energized the 1B-SB safety bus thereby activating the 1B-SB Sequencer and starting the 1B-SB Diesel Generator.

The AO immediately closed the breaker cabinet and notified the Control Room.Upon notification, the Senior Control Operator (SCO)entered Abnormal Operating Procedure AOP-025, entitled"Loss of One Emergency AC Bus (6.9KV)or One Emergency DC (125V)Bus" for the loss of emergency bus and restored all plant systems to normal operation.

At the time of the incident, the plant was in Mode 4 at 345'F and 350 psig.The de-energization of non-safety related Auxiliary Bus lE also caused the Charging Safety Injection Pumps (CSIP)suction source to automatically transfer from the Volume Control Tank (VCT)to the Refueling Water Storage Tank (RWST).This transfer occurs automatically when both VCT level channels (LT-115 and LT-112)are less than 5X (low low level)or when Safety Injection occurs.This transfer of suction source was due to the de-energization of relays K701 (for LT-115)and K706 (for LT-112)which caused the associated contacts to close and generate a signal to re-position th'e valves.Relay K701 lost power due to a 7.5 KVA Inverter (the normal power supply)being out of service for a maintenance function', the alternate power supply was via Auxiliary Bus 1E.Relay K706 lost power due to a faulty pin on the PIC card which failed to pass the normal power from an uninterruptible source;the backup source was powered via the Auxiliary Bus 1E.The VCT/RWST transfer was caused by a combination of both the 7.5 KVA Inverter being out of service, a defective PIC card in the power supply to the LT-112 relay, and the black out of power panels supplied via Auxiliary Bus 1E.CAUSE The incident was caused by a procedural inadequacy.

The procedure did not clearly state how the check was to be performed.

The AO had performed th'is by using a slight amount of pressure on the release pedal.NRC FORM 344A ($4)3)*U.S.GPO:1 988.0 824 538/455 NRC Form 366A (983)~~LI SEE ENT REPORT (LER)TEXT C TINU ON U.S.NUCLEAR REGULATORY COMMISSION APPROVED OMB NO, 3150-0104 EXPIRES: 8/31/88 FACILITY NAME (I)SHEARON HARRIS PLANT UNIT 1 DOCKET NUMBER (2)YEAR LER NUMBER (61 PNO SEOUENT/AL NUM E rr gf REVIE/ON.ÃNUMBER PAGE (3)TEXT/6 mroo Eooof/4/P///ood, re///orro/HRC Form 35843/(IT)ANALYSIS 05000400$7-0 1 1 0 1 03"0 3 There were no adverse consequences due to this incident.The event resulted in actuation of components on the 1B-SB bus as required by plant design.The event is reportable per 10CFR50.73(a)(2)(iv) which requires reporting of manual or automatic initiation of any Engineered Safety Feature.CORRECTIVE ACTION The defective PIC card in the power supply to LT-112 relay has been replaced.ACTION TO PREVENT RECURRENCE To prevent a recurrence of this event, a change to OST-1023 has been completed.

The procedure now contains the caution statement, NDo not depress the breaker release pedal when breaker'is closed, pedal will trip breaker."'NRC fORM 3EEA'(94(3)w U.S.GPO:1986W624 538/455 0~

~0~~C SQE Carolina Power&Light Company HARRIS NUCLEAR PROJECT P.O.Box 165 New Hill, NC 27562'JUL 22]qRT File Number'SHF/10-13510C Letter Number: HO-870459 (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 87-011-01 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.Revision 1 is being submitted due to a change in why the K706 relay lost power and the corrective action taken.Very truly yours, R.A.Watson Vice President Harris Nuclear Project RAW:skm Enclosure cc: Dr.J.Nelson Grace (NRC-RII)Mr.B.Buckley (NRR)Mr.G.Maxwell (NRC-SHNPP)MEM/HO-8704590/PAGE 1/OS1

~~~~