ML18024A575

RO-50-296/782:Bendix Connectors Used Inside Primary Containment Which Failed post-aging Environ Test Were Modified by Potting Plug & Receptacle Portion of Connectors & Passed 10 Year Qualifying Tests

ML18024A575
Person / Time
Site:	Browns Ferry
Issue date:	12/06/1978
From:	Fox H TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
NUDOCS 7812110168
Download: ML18024A575 (6)

Text

r REGU .OBY INFORMATION D ISTB I BUT 9 SYSTEM (R IDS )

ACCESS I ON NB lks 7812 I.l 0168 DOC.DATE s 78/12/06 NOTARIZED s NO DOCKET ¹ FACILs50-296 BRO1'INS FERRY ¹3, TENNESSEE VALLEY AUTHORITY 05 0002960 AUTH. NAME AUTH()B A FF I LIAT I ON FOX,H.S. TENNESSEE VALLEY AUTH()RITY RECIPE NAME RECIPIENT AFFILIATION O~REILLY, J.P. **REG.2,ATLANTA,OFF.OF THE DIRECTOR

'UBJECTs RO-50-296/782sBendix connectors used inside primary containment. which failed post-aging environ test were modified by potting plug 8, receptacle portion of connectors 8, passed .10 year qualifying tests.

DISTRIBUTION CODE.s A002S COPIES RECEIVEDsLTR > ENCL 0 SIZEs 2 TITLE: INCIDENT REPORTS NO fES s BEG I P I ENT . COPIES REC I P I ENT COP I ES ID CODE/NAME LTT.B ENCL ID CODE/NAME LTTB ENCL ACTIONs 05 BC ORB//3 04 04 INTERNALs G FI F 02 NBC PDB 01 01

,0. 02 02 11 MIPC 03 03 14 HANAUER 0.1 -0,1 15 NOVAK/CHECK O.I, 01 16 EEB 0.1 01 17 AD FOR ENGR 01 01 18 PLANT SYS BR .01, 01 19 I8,C SYS BR 01 0.1 20 AD PLANT SYS. 0,1 0.1 21 AD SYS/PBOJ 01 01 22 BEAC BAFT BR 0.1 .0 j 23 ENGR BR 0.1 01 0 24 KREGR/COLLNS 0,1 O.l 25 PNR SYS BR 0.1 0.1 26 VOLMR/HOUSTN 01 01 E JORDAN/IE 01 01 NRC PDR .I I REG FILE I I EXTEBNALs 03 LPDB 01 01 04 NS IC 01 01 27 ACRS 16 16

.DEC 18 19/0 0

TOTAL NUMBER OF COP I ES REQUI RED- LTTB 45 ENCL 45

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fENNESSEE VALLEY AUTHORITY CHATTANOOGA. TENNESSEE 37401 December 6, 1978 REGULATORY DOCKET Ffi E MPY' Mr. James P. O'Re:lly, Director U.S. Nuclear Regulatory Commission Office of Inspection and Enforcement Region XX 101 Marietta Street, Suite 3100 Atlanta, Georgia 30303

Dear Hr. O'Reilly:

TENNESSEE VALLEY AUTHORITY BROWNS FERRY NUCLEAR PLANT UNXT 3 - DOCKET NO. 50-296 FACILITY OPERATING LXCENSE DPR&8 - REPORTABLE OCCURRENCE REPORT BFRO-SO-296/782 My letter to you dated February 28, 1978, provided det:ails concerning the Bendix connectors of the type used inside the primary containment which failed a post-aging environmental test at Wyle Labozatories tooting facility.

The follm~g information,io provided which wa feel will close out this occurrence.

Xn February 1978, Wyle Laboratories completed qualification tests on all types of electrical connectors used at Browno Ferry Nuclear Plant units 1, 2, and 3. Of these connectors, the type used in the unit 3 drywell (Bendix) i failed the tests. The failures re attributed to deterioration caused by excessive heat-accelerated aging of. the connectors. Xt wao believed that they were aged at too high a temperature which deteriorated the neoprene seals in the connectors. This explanation was presented to NRC'o Washington office, and it wao agreed that additional tests should be run.

Xn March 1978, Wyle Laboratorieo completed the additional qualification tests on Bendix connectors. Of the ten Bendix connectors tested, three, which were 480-volt connectors, failed. However, another 480volt Bendix connector which had been modified by potting both the plug and receptacle pox'tion of the connector passed all the tests for a 2-year life. TVA proposed to NRC's Washington office that potting all the safety-xelated connectors in the unit 3 containment would ensure safe and proper operation of. the unit until the planned refueling outage in September 1978. This would allow TVA the neceooax'y time to make provisions to/splice out the connectors or to requalify the potted connectors for a longer life. NRC agreed to TVA'o proposal. The connectors in unit 3 were potted, and the unit wao xeturned to service.

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Hr.. James P. O'Reilly, Director December 6, 1978 In September 1978, Pyle Laboratories completed the additional qualification tests on potted"'Bendix connectoxs. Of the eight connectors tested, all eight passed the tests. These tests qualified potted Bendix connectors for a 10-year life. On September 25, 1978, a lotter from J. E. Gilleland eras sent to T. A. Ippolito, of NRC, explaining that the eristing connectors at Brogans Ferry Nuclear Plant had been environmentally qualified fox a 10-year life when potted.

~Very truly yours, TENNESSEE VALLEY AUTHORITY H. S. Fox Director of Power Pz'oduction Vc! Director (3)

Office of kfanagement Information and Program Control U.S. Nuclear Regulatory Commission Haohington, D.C. 20555 Director (40),

Office of Inspection and Enforcemant U.S. Nuclear Regulatory Commission Washington, D.C, 20555

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