ML17265A403

Part 21 Rept Re W DB-75 Circuit Breakers W/Missing Tripper Bar Tabs.Caused by Intermittent Failure to Close in DB-75 B EDG Supply Circuit Breaker to Bus #16.Licensee Nuclear Engineering Personnel Are Performing Vendor Document Review

ML17265A403
Person / Time
Site:	Ginna
Issue date:	08/12/1998
From:	Mecredy R ROCHESTER GAS & ELECTRIC CORP.
To:	NRC
References
REF-PT21-98 NUDOCS 9808170270
Download: ML17265A403 (14)

Text

CATEGORY 1 REGULAT Y INFORMATION DISTRIBUTIO YSTEM (RIDS)

ACCESSION NBR:9808170270 DOC.DATE: 98/08/12 NOTARIZED: NO DOCKET FACIL:50-244 Robert'mmet Ginna Nuclear Plant, Unit 1, Rochester G 05000244 AUTH. NAME AUTHOR AFFILIATION MECREDY,R.C'. Rochester Gas & Electric Corp.

RECIP.NAME RECIPIENT AFFILIATION NRC - No Detailed Affiliation Given

SUBJECT:

Part 21 rept re W DB-75 circuit breakers w/missing Tripper Bar Tabs. Caused by intermittent failure to close in DB-75 "B" EDG supply circuit breaker to BUS 516.Licensee Nuclear Engineering personnel are performing vendor document review.

DISTRIBUTION CODE: IE19T COPIES RECEIVED:LTR )

TITLE: Part 21 Rept (50 DKT)

ENCL L SIZE:

E NOTES:License Exp date in accordance with 10CFR2,2.109(9/19/72). 05000244 G

RECIPIENT COPIES 9 RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD1-1 PD 1 1 VISSING,G. 1 1 INTERNAL. 1 NRR/DRPM/PECB 1 1 NRR/DRPM/PECB/B 1, 1 PDR WARD, M. 1 1 RES/DET/EIB 1 1 RGN1 1 1 RGN2 1 1 RGN3 1 1 RGN4 1 1 EXTERNAL: INPO RECORD CTR 1 1 NOAC SILVER,E 1 1 NRC PDR 1 1 NUDOCS FULL TXT 1 1 D THING 0 E

OOQuMpgy N HAs BEEN scANN8lP NOTE TO ALL NRIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE. TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRIBUTION LISTS OR REDUCE THE NUMBER OF COPIES RECEIVED BY YOU OR YOUR ORGANIZATION, CONTACT THE DOCUMENT CONTROL DESK (DCD) ON EXTENSION 415-2083 FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 15 ENCL 15

AUG-12-1998 14: 89 GIHHA STATION. 716 771 3988 P.82r85 AhlP ROCHESTER GASAND ELECTRIC CORPORATION 89EASTAVENUE. ROCHESTER, 'NY. 146490001 AREA COOE 116.S46.2700 ROBERT C, MECREDY

~i+Q ~f~vl'8/hi Hvcleor Opamlions August 12 19 9 8 U.S. Nuclear Regulatory Commission Operations Center Facsimile Number 301-816-5151 Telephone Number 301-816 .5100

Subject:

Initial Notification of 10 CFR Nuclear Power Plant Part 21'Defect R.E. Qinna Docket No. 50-244 In accordance with 10 CFR Bart 21, Reporting of Defects and Noncompliance, Section 21 (d) (3) (i) , which requires "Initial notification by facsimile", the enclosed initial notification is provided. Nritten notification, in accordance with 10 CFR part 21, Section 21 (d) (3) (ii) , will be pravide4 by September 11, 1998.

Ver truly yours, Robert C. Mecred Enclosures

'Terry A. White Manager, Operations

+chester Gas and Electric Corporation R. E. Ginna Nuclear Power Plant 1503 Lake Road Ontario, N.Y. 14519 Phone: (716) 771-3667 Fax: (716) 771-3901 9808170270 980812 email: 'Ihrry Whitedgmail.zI,e.corn PDR ADOCK 05000244 S PDa j

L AUG-12-1998 14: 89 INNA STATION 716 771 3988 P,83r85

) Page 1 10CFR21 INITIAL FACSIMILE NOTIFICATION Z. NAME AND ADDRESS OF THE INDIVIDUAL INFORMING THE COMMXSSXON:

NAME Robert C. Mecredy Vice President Nuclear Operations Group ADDRESS Rochester Gas 6. Electric Corporation 89 East Avenue Rochester, New York 14649 XX. IDENTIFICATION OF THE FACILITY, THE ACTIVITY~. OR THE BASIC COMPONENT SUPPLZED FOR SUCH FACILITY WHICH FAILS TO COMPLY OR CONTAINS A DEFECT:

The facility is the R.E. Ginna Nuclear Power Plant. The basic component is a Westinghouse DB-75 circuit breaker. This component was installed in a Class 1E Safety Related Bus. The breaker is the 'B'iesel Generator Supply breaker to Bus 16 (Safety Related Bus).

III. IDENTIFICATION OF THE FIRM SUPPLYING THE BASIC CONS'gRUCTZNG THE FACILITY OR COMPONENT WHICH FAILS TO COMPLY OR CONTAINS A DEFHCT-'he breaker is manufactured by:

Westinghouse Electric Corporation Nuclear Services Integrated Division.

Box 78 Pittsburgh, PA 15230-oo78 IV. NATURE OF THE DEFECT OR FAILURE TO COMPLY AND THE SAFETY HAZARD WHICH IS CREATED OR COULD BE CREATED BY SUCH DEFECT OR FAILURE TO COMPLY:

The DB-75 breaker was retrofitted with an AMPTECTOR solid state trip unit per Westinghouse instruction Z.B. 33-850-6 that instructed the technician to remove all tripper bar tabs from the tripper bar. Subsequently the instruction bulletin was revised to specifically. leave the center tripper bar tab installed. There were no notifications to the plant to re-install the center tripper bar tabs on previously modified breakers, The absence of the center tripper bar tab allowed two tripper bar bushings to fall from their housing and is believed to, over time, bend the tripper bar so that it would not fully reset. The failure of the tripper bar to fully reset caused intermittent failure to close on the DB-75 generator supply breaker to Safety Related Bus 16.

With the identified deficiency in the 'B'iesel Generator

~B'iesel supply breaker it is possible that a single failure could render both safety trains incapable of performing their safety functions (buses 14 and 16). This deficiency constitutes a substantial safety hazard.

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'UG-12-1998 14:89 G INNA STAT10N 716 771 3988 P.84r85 I

V. THE DATE ON WHICH THE INFORMATION OF SUCH DEFECT OR FAILURE TO COMPLY WAS OBTAINED:

The information was obtained on July 27, 1998 after discussions with Westinghouse repxesentatives. The missing tripper bar tabs were discovered March 25, 1998 during troubleshooting of the latest failure. The method of notification by the vendor was not determined until July 27, 1998.

VX. XN THE CASE OF A BASIC COMPONENT WHICH CQNTAXNS A DEFECT OR FAXLS TO COMPLY, THE NUMBER AND LOCATION OF ALL SUCH COMPONENTS IN USE ATI SUPPLIED FOR~ OR BEING SUPPLIED FOR GINNA STATXON:

There are six Westinghouse DB-75 breakers installed at Ginna in safeguards busses 14 and 16. There is also one Safety Related spare breaker. The Bus 14 and 16 Safety Related bus feeds and the two (2) bus tie breakers between Buses 14 and 16 wexe correctly modified per the revised instructions. The original Spare DB-75 breaker was also correctly modified prior to being installed into the 'A'iesel Generator supply breaker position.

Between 3/85 and 2/88 the 'B'iesel Generator supply breaker was installed with the incorrect modification. Xn 2/88 the DB-75 breaker installed in the 'A'iesel Generator supply breaker on Bus 14, was incorrectly modified in the. same manner as the 'B'iesel Generator supply breaker. Between 2/88 and 5/96 both Diesel Generator output breakers to Bus 14 and 16 were installed with incorxect modifications. In 5/96 the spare DB-75 breaker, 96-.04, was installed in the 'A'iesel Generator supply breaker position. Breaker 96-04 was modified correctly per the current revision of the installation instructions. Although the potential for failure existed, the breakers were tested with regular surveillance tests to pxove operability and the failure mechanism is of the nature that degrades over time. The missing tripper bax tab would not immediately fail the breaker upon removal.

V

. RUG-1'2-199S 14: 18 INNA STAT ION VI'I ~ THE CORRECTIVE ACTION WHICH HAS BEEN ) XS BEING ) OR WILL BE TAKEN; THE NAME OF THE lNDXVIDUAL OR ORGANIZATION RESPONSZBLE FOR THE ACTION; AND THE LENGTH OF TIME THAT HAS BEEN, OR WILL BE TAKEN TO COMPLETE THE ACTION:

All DB-'75 breakers were inspected at the point the missing center trippex bar tab was discovered- Maintenance personnel installed center tripper bar tabs on the 'B'iesel Generator supply breaker and Spare breaker, previously installed in the

'A'iesel 'Generator supply breaker position. Nuclear engineering is performing a vendor document review which is in its final stages. The review will verify all breakers are properly configured per applicable vendor documentation. The results of the review is being incorporated into mai'ntenance procedures. All corrective actions are scheduled to be completed by December 31, 1998.

'XXI. ANY ADVXCE RELATED TO THE DEFECT OR FAILURE TO COMPLY ABOUT THE FACILITY, ACTIVITY, OR BASIC COMPONENT THAT HAS BEEN, IS BEING, OR WILL BE GIVEN TO PURCHASERS QR LICENSEES:

The tripper bar tab installation is verified by visual inspection, possible with the breaker in service. An industry notification was distributed at the time the tripper bar tab vas discovered to be improperly modified.

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POWER REACTOR EVENT NUMBER: 34632 FACILITY: GINNA REGION: 1 NOTXFICATION DATE: 08/12/98 UNIT: [1] [ ] [ STATE: NY NOTIFICATION TIME: 14:10 [ET]

RK TYPE: [1] W-2-LP EVENT DATE: 07/27/98 EVENT TIME: 12:00[EDT]

NRC NOTIFIED BY: BOB MECREDY LAST UPDATE DATE: 08/12/98 HQ OPS OFFICER: DICK JOLLIFFE

. NOTIFICATIONS EMERGENCY CLASS: NOT APPLICABLE 10 CFR SECTION: DAVID SILK, R1 RDO CDEG 21.21(c)(3)(i) DEFECTS/NONCOMPLIANCE EDWARD McALPINE, R2 RDO MARK RING, R3 RDO'ARY SANBORN, R4 RDO VERN HODGE NRR UNXT SCRAM CODE RX CRIT INIT PWR INIT RX MODE CURR PWR CURR RX MODE N Y 100 POWER OPERATION 100 POWER OPERATION EVENT TEXT 10CFR21 WESTINGHOUSE DB-75 CIRCUIT BREAKERS WITH MISSING TRIPPER BAR TABS THERE ARE SIX WESTINGHOUSE DB-75 CIRCUIT BREAKERS INSTALLED AT GINNA IN SAFEGUARDS BUSES ¹14 AND ¹16 AND ONE UNINSTALLED SAFETY RELATED SPARE.

ON 03/25/98, DURING TROUBLESHOOTING ACTIVITIES, THE LICENSEE DISCOVERED THAT THE CENTER TRIPPER BAR TABS WERE MISSING FROM A WESTXNGHOUSE DB-75 CIRCUIT BREAKER INSTALLED IN THE 'B'MERGENCY DIESEL GENERATOR (EDG)

SUPPLY CIRCUIT BREAKER TO THE CLASS 1E SAFETY RELATED BUS ¹16 AT GXNNA.

PRIOR TO 03/25/98, GINNA MAINTENANCE TECHNICIANS HAD RETROFITTED THE

'B'DG DB-75 SUPPLY CIRCUIT BREAKER WITH AN AMPTECTOR SOLID STATE TRIP UNIT PER WESTINGHOUSE INSTRUCTION I.B. 33-850-6 THAT INSTRUCTED THE TECHNICIANS TO REMOVE ALL TRIPPER BAR TABS FROM THE TRIPPER BAR.

SUBSEQUENTLY, THE WESTINGHOUSE XNSTRUCTION BULLETIN WAS REVISED TO SPECIFICALLY LEAVE THE CENTER TRIPPER BAR TAB INSTALLED. THERE WERE 0 NO WESTINGHOUSE NOTIFICATIONS TO GINNA TO REINSTALL THE CENTER TRIPPER BAR TABS ON PREVIOUSLY MODIFIED DB-75 CIRCUIT BREAKERS.

THE ABSENCE OF THE CENTER TRIPPER BAR TAB ALLOWED TWO TRIPPER BAR BUSHINGS TO FALL FROM THEIR HOUSING AND IS BELIEVED TO, OVER TIME, BEND THE TRIPPER BAR SO THAT IT WOULD NOT FULLY RESET. THE FAILURE OF THE TRIPPER BAR TO FULLY RESET CAUSED THE INTERMITTENT FAILURE TO CLOSE ON THE DB-75 'B.'DG SUPPLY CIRCUIT BREAKER TO BUS ¹16.

W ITH THE IDENT IF IED I I DEF C ENCY I I N THE B EDG SUPPLY C IRCU T BREAKER F IT IS POSSIBLE THAT A SINGLE FAILURE COULD RENDER BOTH SAFETY TRAINS INCAPABLE OF PERFORMING THEIR SAFETY FUNCTIONS (BUSES ()16 AND ()16) ~

g "/0 0of (Continued on next page)

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P FACILITY: GINNA PAGE g 2 OF EVENT NUMBER: 34632 THIS DEFICIENCY CONSTITUTES A SUBSTANTIAL SAFETY HAZARD.

BETWEEN MAR 85 AND FEB 88, THE DB-75 'B'DG SUPPLY CIRCUIT BREAKER WAS INSTALLED WITH THE INCORRECT MODIFICATION. IN FEB 88, THE DB-75 CIRCUIT BREAKER INSTALLED IN THE 'A'DG SUPPLY BREAKER ON BUS g14 WAS INCORRECTLY MODIFIED. IN THE SAME MANNER AS THE 'B'DG SUPPLY CIRCUIT BREAKER.

BETWEEN FEB 88 AND MAY 96, BOTH EDG OUTPUT CIRCUIT BREAKERS TO BUSES N.4 AND 516 WERE INSTALLED WITH THE INCORRECT MODIFICATIONS.

IN MAY 96, THE ORIGINAL SPARE DB-75 CIRCUIT BREAKER, f96-04, WAS INSTALLED IN THE 'A'DG SUPPLY BREAKER POSITION. CIRCUIT BREAKER 596-04 HAD BEEN MODIFIED CORRECTLY PER THE CURRENT REVISION OF, THE WESTINGHOUSE INSTALLATION INSTRUCTIONS PRIOR TO BEING INSTALLED INTO THE 'A'DG SUPPLY CIRCUIT BREAKER POSITION.

ON, 03/25/98, THE LICENSEE INSPECTED ALL WESTINGHOUSE DB-75 CIRCUIT BREAKERS AT GINNA. PLANT MAINTENANCE TECHNICIANS INSTALLED CENTER TRIPPER BAR TABS ON THE 'B'DG SUPPLY CIRCUIT 'BREAKER AND THE SPARE CIRCUIT BREAKER, PREVIOUSLY INSTALLED IN THE 'A'DG SUPPLY CIRCUIT BREAKER POSITION.

THE DB-75 CIRCUIT BREAKERS ON BUSES g14 AND 416 AND THE TWO BUS TIE CIRCUIT BREAKERS BETWEEN BUSES 514 AND g16 HAD BEEN CORRECTLY MODIFIED PER THE REVISED WESTINGHOUSE INSTRUCTIONS.

ALTHOUGH THE POTENTIAL FOR FAILURE EXISTED AT GINNA, THE WESTINGHOUSE DB-75 CIRCUIT BREAKERS WERE TESTED WITH REGULAR SURVEILLANCE TESTS TO PROVE OPERABILITY AND THE FAILURE MECHANISM IS OF THE NATURE THAT DEGRADES OVER TIME. THE MISSING TRIPPER BAR TAB WOULD NOT IMMEDIATELY FAIL THE CIRCUIT .BREAKER UPON REMOVAL.

1 LICENSEE NUCLEAR ENGINEERING PERSONNEL ARE PERFORMING A VENDOR DOCUMENT REVIEW TO VERIFY THAT.ALL WESTINGHOUSE DB-75 CIRCUIT BREAKERS ARE PROPERLY CONFIGURED IN ACCORDANCE WITH APPLICABLE VENDOR DOCUMENTATION.

ALL LICENSEE CORRECTIVE ACTIONS ARE SCHEDULED TO BE COMPLETED BY 12/31/98.

ON 03/25/98, THE LICENSEE DISTRIBUTED A NOTIFICATION OF THIS CONDITION TO INDUSTRY REPRESENTATIVES. THE CENTER TRIPPER BAR TAB INSTALLATION CAN BE VERIFIED BY VISUAL INSPECTION, POSSIBLY WHILE THE CIRCUIT BREAKER IS IN SERVICE.

SPECIFIC INFORMATION FOR THIS REPORT WAS OBTAINED DURING DISCUSSIONS WITH WESTINGHOUSE REPRESENTATIVES ON 07/27/98.

THE LICENSEE PLANS TO SUBMIT A WRITTEN 10CFR21 REPORT OF THIS CONDITION TO THE NRC BY 09/11/98.

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