ML17251A537

LER 89-002-00:on 890506,safeguards 480 Volt Bus 14 Tripped During Offsite Power Mod Relay Testing.Caused by Typo in Mod Test Procedure That Called for Wrong Terminal Block to Be Opened.Error corrected.W/890605 Ltr

ML17251A537
Person / Time
Site:	Ginna
Issue date:	06/05/1989
From:	Backus W, Mecredy R ROCHESTER GAS & ELECTRIC CORP.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-89-002, LER-89-2, NUDOCS 8906140291
Download: ML17251A537 (16)

Text

~

AC CELE P <TED Dl STMBt'T1 0% DEMO~ STRXT104 & ZTEk REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:8906140291 DOC.DATE: 89/06/05 NOTARIZED: NO DOCKET g FACIL:50-244 Robert Emmet Ginna Nuclear Plant, Unit 1, Rochester G 05000244 AUTH. NAME AUTHOR AFFILIATION BACKUS,W.H. Rochester Gas & Electric Corp.

MECREDY,R.C. Rochester Gas & Electric Corp.

RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER 89-002-00:on 890506,safeguards bus undervoltage during relay testing due to inadequate procedure review.

W/8 DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR ENCL SIZE:

TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.

NOTES:License Exp date in accordance with 10CFR2,2.109(9/19/72). 05000244 RECIPIENT COPIES RECIPIENT COPIES ID LTTR ENCL ID CODE/NAME LTTR ENCL CODE/NAME'D1-3,LA 1 1 PD1-3 PD 1 1 JOHNSON,A 1 1 D

INTERNAL: ACRS MICHELSON 1 1 ACRS MOELLER 2 2 ACRS WYLIE 1 1 AEOD/DOA 1 1 S AEOD/DSP/TPAB 1 1 AEOD/ROAB/DSP 2 2 DEDRO 1 1 IRM/DCTS/DAB 1 1 NRR/DEST/ADE 8H 1 1 NRR/DEST/ADS 7E 1 0 NRR/DEST/CEB 8H 1 1 NRR/DEST/ESB 8D 1 1.

NRR/DEST/ICSB 7 1 1 NRR/DEST/MEB 9H 1 1 NRR/DEST/MTB 9H 1 1 NRR/DEST/PSB 8D 1 1 NRR/DEST/RSB 8E 1 1 NRR/DEST/SGB 8D 1 1 NRR/DLPQ/HFB 10 1 1 NRR/DLPQ/PEB 10 1 1 NRR/DOEA/EAB 11 1 1 REB/RPB 10 2 2 NUDOCS-ABSTRACT 1 1 EG F 02 1 1 RES/DSIR/EIB -1 1 PRAB 1 1 RGN1 FILE 01 1 1 EXTERNAL: EG&G WILLIAMS,S 4 '4 FORD BLDG HOY,A 1 1 L ST LOBBY WARD 1 1 LPDR 1 1 NRC PDR 1 1 NSIC MAYS,G 1 1 NSIC MURPHYIG A 1 1 D S

D D

NOrE 'IO ALL>>RIDS>> RECZPZZNrS:

S PLEASE HELP US RXN Pl-37 (EXr. 20079) K)

LISTS R)R DOCUMENIS K) REDUCE WASTE!

ELIMINATE YOUR NAME YOU DON'T NEED!

~

CGNZACT 'IHE DCKX>~r CXÃZK)L DESK, DIBTRIBVTION

~ TOTAL NUMBER OF COPIES REQUIRED: LTTR 43 ENCL 42

ROCHESTER GAS AND ELECTRIC CORPORATION ~ 89 EAST AVENUE, ROCHESTER, N.Y. 14649.0001 June 5, 1989 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555

Subject:

LER-89-002, Safeguards Bus Undervoltage During Relay Testing Due To Inadequate Procedure Review Causes the "A" Emergency Diesel Generator To Automatically Start and Accept Load R.E. Ginna Nuclear Power Plant.

Docket No. 50-244 In accordance with 10 CFR 50.73, Licensee Event Report System, item (a)(2)(iv) which requires a report of, "any event or condition that resulted in manual or automatic actuation of any Engineered Safety Feature (ESF) including the Reactor Protection System (RPS)", the attached Licensee Event Report LER-89-002 is hereby submitted.

This event has in no way affected the public's health and safet:y.

Very truly yours, Robert C. Mecre General Manager Nuclear Production XC: U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406 Ginna USNRC Senior Resident Inspector 890614029k 890605 PDR ADOCK 05000244 PDC

0 eeAC terre 200 I04) I US. NVCLCAA ACOULATO1Y COMMlSEION AttAOVCO OMO HO. 2(50 0(Ore LICENSEE EVENT REPORT (LER) EX4150 0/Er/05 FACILITY NAME lll OOCXCT NVMOCA Ql R.E. Ginna Nuclear Power Plant a egu s us n ervo tage During Re ay Testing Due To Inadequate 060004410F06 Procedure Review Causes The NAN Emer enc Diesel Generator To Start and Acce CVCIIT CATE I ~ I LCA NVMEEA (4 ACFOAT OATC III OTNC1 FACILITIEC INVOLVCO III MOHTre OAY YEA)I YEAN 550UlNTIAL ee" ACVAIOee MONTH OAY ~ ACILITYreAULO OOCXCT HVMOCA(5)

NUM051 rh reUeeetA YEAN 0 5 0 0 0 0 5 0 6 8 9 8 9 0 02 00 60589 0 5 0 0 0 Ot 5 A AT INC

'CHIC t)CFOIIT IC CUOMITTCO W15VAHT T 0 THC hlovIACMCNTC Ot 10cth fj: /crete rer ee errer el IIee leIIeeeeet/ Ill MOOC (0)

10. 002 (0) 20.e00(el 00.) 24)4 Illrl 22.)1(01 FOIYC1 20.000(e) ll) IO 00 J4(el()i ~ OQ24IQIlrl TS.T I (e)

LcvcL 0 0 0 20.400 ie) I) I I 5 I ~OM(e)QI ~ O.T l(e)QI(re) OTHCA /Stecrry Ie AArrrect terra rert Ie TrrL HAC teeter SO.COO 4) I) l(WI 00.224IQII4 50,724)Q)lrW)IAI JCOA/

20 ACE 4)(l ) (H ) 50,224)QI(0) ~ OQ24)(l) (rW I IOI 2O.COE 4) II l le I 50.7 2 4 I 4 I I Wl 50.)l( ~ )Q)I ~ I LICCHCCE CONTACT tOll 'TNIC LEA Ill)

NAME TCLCFHOHC HUMEEA Wesley H. Backus At(CA COOC Technical Assistant to the Operations Mana er 315 COMtLCTC ONE LINC tOA CACN COMFONENT FAILU15 OCCCAIECO IN THIS ACFOAT Ill)

CAV5E 5YCTCM CO UFO H CHT MAHUFA('e TUACA EtOrll'AEI,C 4, '~ yec+jgt@ COMFOHEN'T MANVFAC TVAEA EFOATAOL IP;44%~@y+<4 Axe x)yh.

EUttLCMCNTAL ACFOAT CXFECTCO (l4 EXFCCTCO MONTH CAY YCAA LUIM<$5)ON CATE IIII YCC /I/yre, cterterre CXFCCTCO SVSMISSIOH OATS/ HO AJCTAACT IL/eUt ce taxi terra, tr.. rtteererrere/y IIIHar rletrretecr tytear1He Here) IIOI On May 6, 1989 at 0946 EDST with the reactor in the Cold/Refueling Shutdown Condition, safeguards 480 volt Bus 14 tripped during offsite power modification relay testing. This caused the QAQ Emergency Diesel Generator to automatically start and connect to safeguards 480 volt Bus 14.

The underlying cause of the event was due to a typographical error in the Modification Test Procedure that called for the wrong terminal block to be opened for blocking the above bus trip. This typographical error was due to inadequate proofread-ing of last minute changes to the procedure.

Corrective action taken was to identify and correct the procedure error and to restore safeguards 480 volt Bus 14 to its normal power supply.

NAC Freer 200

(&45)

U.S. IIUCLSA+ IIlOULATOIYCOMMISSIOM fj HAC Farm SSSA lslsl LICENSEE EVENT REPORT ILER) TEXT CONTINUATION AFFIIOYSO OMs IIO SISO&IOo SXFIASS SISIISS FACILITY SIAM@ III LSII IIUMSSII LSI SSQVSHTIAL ASYISION MVM SA MVM Se R.E. Ginna Nuclear Power Plant: o s o o o 244 89 002 0 0 020~0 6 TxxT /IF more AMoe e leeveee. Vee eoebFoneF HEMIC foml ~'ll I ITS I ~ PRE-EVENT PLANT CONDITIONS The unit was in cold/refueling shutdown for the Annual Refueling Maintenance Outage. An offsite power reconfigura-tion modification was in progress per ERR-4525.

DESCRIPTION OP EVENT'.

DATES AND APPROXIMATE TIMES FOR MAJOR OCCURRENCES:

o May 6, 1989, 0946 EDST: Event date and time.'

May 6, 1989, 0946 EDST: Discovery date and time.

o May 6, 1989, 0952 EDST: Safeguards Bus 14 Normal Power Supply Restored.

o May 6, 1989, 0952 EDST: Safeguards Bus 14 "A" Emergency Diesel Generator Power Supply Terminated and "Bss Emergency Diesel Generator Stopped and Lined Up for Auto Standby.

B. EVENT:

On May 6, 1989 at 0946 EDST, the reactor was in the cold/refueling shutdown condition. Relay testing was in progress on 4160 volt safeguards Bus 12A per step 6.2.5.1.1 of station modification procedure SM-4525.15. During the performance of relay testing on 12A, differential relay 87B/12A operated lockout bus relay 86B/12A, which tripped the station service transformer breaker (14SS-4160V) causing an under-voltage condition on 480 volt safeguards Bus 14.

The "A" Emergency Diesel Generator Automatically started, as required, due to the undervoltage condition on 480 volt safeguards Bus 14 and sub-sequently connected to Bus 14 as required.

'vAC FOAM SSSA IS4SI

4 U.S, NUCLCAR RlOULATORY COMMISSION NRC tat~ 2SSA I 0421 LICENSEE EVENT REPORT (LER) TEXT CONTINuATION AttROVCO OMS NO 2150MI04 Txt>RSS SISICSS tACILITYNAME III OOCKCT NUM02R 12I LSR NUM02R ISI tAOI I21

• SSOVSNTIAL RSVOlON NUM SR NUM SR 244 002 00 03OF06 T29cT Ilfecece Nwce e ~

R.E. Ginna Nuclear Power Plant eee acccRAeMI NJIC Fcecn ~'el IITI o s o o o 8 9 C. INOPERABLE STRUCTURES t COMPONENTS t OR SYSTEMS THAT CONTRIBUTED TO THE EVENT:

None.

D. OTHER SYSTEMS OR SECONDARY FUNCTIONS AFFECTED:

None.

E. METHOD OF DISCOVERY:

The event was immediately apparent due to alarms and indications in the Control Room.

F. OPERATOR ACTION:

Following the Bus 14 undervoltage and "ATI Emergency-Diesel Generator Automatic Start and the Tie Breaker Closure to Bus 14, the Control Room Operators immed-iately verified proper voltage on Bus 14 and that the "A" Emergency Diesel Generator displayed proper voltage and frequency.

G. SAFETY SYSTEM RESPONSES:

The "A" Emergency Diesel Generator automatically started and tied into 480 volt safeguards Bus 14 due to a valid undervoltage signal on Bus 14.

IZZ. CAUSE OP A. IMMEDIATE CAUSE:

The automatic actuation of the "A" Emergency Diesel Generator and subsequent tie into Bus 14 was due to a valid undervoltage signal from the Bus 14 undervoltage monitoring system.

wRc foRM ssee

<942 I

U.S. NUCLSAII IISOULATOIIT COMMISSION NIIC FaNN S~SA 10451 LICENSEE EVENT REPORT ILER) TEXT CONTINUATION AFFAOVEO OMS NO 315OWIOI SKFIIISS SISIISS FACILITY NAMS 111 OOCKST NUMSEII Ill LSII NUMSSII I ~ I 5 5 0 V 5 N 'I I A L hl VISION H VM tI II NVMtta R.E. Ginna Nuclear Power Plant

'fQ(T IJT maat t 5 tt it Itt~ K att ~ )YACC FaaIII JC54'll (171 o s o o o 24 489 0 0 2 0 0 0 40i0 6 B. INTERMEDIATE CAUSE:

The valid undervoltage signal was due to an operation of 86B/12A lock-out relay during Bus 12A relay testing which inadvertently tripped the station service transformer breaker (14SS-4160V) to Bus 14.

The 86B/12A lock-out relay trip contacts for breaker (14SS-4160V) were not blocked from operating prior to testing because of a typographical error in the SM-4525.15 procedure which called for the wrong terminal block to be opened for blocking the trip (i.e. TFH-10 was opened and TFF-10 should have been opened).

C. ROOT CAUSE:

The root cause of the event was an inadequate technical .

proofreading review of a retyped version of SM-4525.15 subsequent to some last minute changes. This led to the typographical error that caused the event not being identified and corrected prior to the procedures use.

ANALYSIS OF EVENT The event is reportable in accordance with 10 CFR 50.73, Licensee Event Report System, item (a)(2)(iv), which requires reporting of, "any event or condition that resulted in manual or automatic actuation of any Engineered Safety Feature (ESF) including the Reactor Protection System (RPS)". The starting of the "A" Emergency Diesel Generator was an automatic actuation of an ESF system.

An assessment was performed considering both the safety consequences and implications of this event with the following results and conclusions:

NIIC FOSM SC A 5 ll

U.S. NUCLfAIIASOULATONY COMMISSION NIIC farm 554A 10411 LICENSEE EVENT REPORT ILER) TEXT CONTINUATION AffIIOVfOOMS NO SISOWIOS fX ~ Illf5 llSI/55 5 AC I LITT N AM5 I1 I OOCIIfT NUMlfllIf) Lfll NUMOflI ISI fAOf ISI SSQVSHTIIL rr 5 v rs ro N

>>VLI 5 1 rrV>> SA R.E. Ginna NUclear'Power Plant o s o o o 2 4 4 8 90 0 2 0005 OF 0 6

>get IIfmore N>>ce>> reer>>ee. r>>e osrv>>reI HlIC forrrr ~ 5 I IITI There were no operational or safety consequences or implications attributed to the starting of the "A" Emergency Diesel Generator and subsequent tie breaker closure to Bus 14 because:

0 The "A" Emergency Diesel Generator and tie-breaker closure to Bus 14 operated as designed.

0 Bus 14 normal power was restored in approximately 6 minutes.

0 The other train of safeguards power was energized and available at all times.

0 Offsite power was available throughout the event.

V. CORRECTIVE ACTION A. ACTION TAKEN TO RETURN AFFECTED SYSTEMS TO PRE-EVENT NORMAL STATUS:

.The error in the procedure was identified and changed.

0 The terminal blocks were then changed to their required positions.

0 Normal power was restored to Bus 14 and the "A" Emergency Diesel Generator was stopped for automatic standby. and'ealigned N II C f 0 Ir rrr 554 L IS 551

U.5. NUCLCAII (15QULA'IOIIY COMMISSION N(IC rrrM 555A 19r151 LICENSEE EVENT REPORT ILER) TEXT CONTINUATION ATTIIOVSO OMO NO, 5190WIOS 5XI'1155 e(SI(55 SACILITY NAMC 111 OOCI(5T NU~SII 111 Llll NUMOlll I ~ I rAOS 151 SSOUSNTIAL iSVISIOH NUM Sw NUM ~ A R.E. Ginna Nuclear Power Plant o 5 o o o 24 489 0 0 2 0 0 6 0 6 55XT ((I'rr(re rr neaeeC wt rrMMSAS((Y(ICFeme ~'r(117)

B. ACTION TAKEN OR PLANNED TO PREVENT RECURRENCE' The existing station policy and guidance on procedure change proofreading and technical review was re-evaluated and is adequate.

The need for adherence to this policy was re-inforced by issuance of a letter to the appro-priate groups by the modification support coordinator.

0 The consequences of the inadequate technical review will be reviewed again with those respon-sible for preparing modification test procedures, prior to the 1990 Annual Refueling and Maintenance Outage.

0 Meaningful cut-off dates will be established for engineering design outputs for the l990 outage, to ensure adequate review of all required tests, and prevent "last minute requirements from being inserted into test procedures without adequate technical review."

VI. ADDITIONAL INFORMATION:

A. FAILED COMPONENTS:

None.

B. PREVIOUS LERs ON SIMILAR EVENTS:

A similar LER event historical search was conducted with the following results: No documentation of similar LER events with the same root cause at Ginna Station could be identified.

C. SPECIAL COMMENTS:

None.

NAC rOklM'SSSA

<9551

if