ML20009F861

Final Deficiency Rept Re Lambda Power Module Failures, Initially Reported 801218.Caused by Use of Halogen Solvent to Clean Capacitor Charge Plates.Epoxy Coating Will Be Added to Exposed Foil by Sprague.Also Reported Per Part 21

ML20009F861
Person / Time
Site:	Bellefonte
Issue date:	07/21/1981
From:	Mills L TENNESSEE VALLEY AUTHORITY
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
REF-PT21-81 10CFR-050.55E, 10CFR-50.55E, NUDOCS 8108030111
Download: ML20009F861 (2)

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TINNESSEI Vd.LLEY AUTHCF?!TY OFFIcbH Cm.

CH ATTA NCC G A. TENN ESS EE 07-.01 400 Chestnut Street Tower II July 21, 1981 , -

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BLRD-50-438/81-05 BLRD-50-439/81-06 Mr. James P. O'Reilly, Director Office of Inspection and Enforcement U.S. Nuclear Regulatory Con: mission Region II - Suite 3100 101 Marietta Street Atlanta, Georgia 30303

Dear Mr. O'Reilly:

BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 - LAMBDA POWER MODULE FAILURES -

BLRD-50-438/81-05, BLRD-50-439/81 FINAL REPORT The subject deficiency was initially reported to NRC-0IE Inspector R. W. Wright on December 18, 1980, in accordance with 10 CFR 50.55(e) as NCR BLN EEB 8006. This was followed by our first interim report dated January 19, 1981. Enclosed is our final report. We consider 10 CFR Part 21 to be applicable to this deficiency.

If you have any questions concerning this matter, please get in touch with D. L. Lambert at FTS 857-2581.

Very truly yours, TENNESSEE VALLEY AUTHORITY s.

L. M. Mills, Manager Nuclear Regulation and Safety Enclosure cc: Mr. Victor Stello, Jr., Director (Enclosure)

Office of Inspection and Enforcement U.S. Nuclear Regulatory Coc: mission Washington, DC 20555 7

8108030111 010721 DR ADOCK 05000 g A-z w Laco.x E m x

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ENCLOSURE BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 LAMBDA POWER MODULE FAILURES BLRD-50-438/81-05, BLRD-50-439/81-06 10 CFR 50.55(e)

FINAL REPORT.

Description of Deficiency In the process of cleaning and preparing capacitor charge plates for Lambda type LXS-E-24-R power supplies, a solvent was applied which adversely affected the dielectric substance. The solvent's .

contamination of the dielectric results in an inability to fully charge the capacitor plates and may result in effectively short circuiting the capacitor.

Safety Implications The short circuiting of the subject capacitors could result in the power supply's diode failure and subsequently in a discontinuation of a regulated power source. Loss of power supply in the essential controls and instrumentation would degrade the safe operation of the plant.

Corrective Action The Bailey Meter Company supplies the subject printed circuit boards (PCB) for the Lambda type LXS-E-24-R power supplies. Bailey Meter has informed the NSSS supplier (Babcock & Wilcox) that they will change their procedure concerning cleaning of the PCB's. In the future',

Bailey Meter Company will clean the subject PCB's without the subject capacitors installed. A halogen cleaning solvent will continue to be used.

Bailey Meter Company has informed the capacitor manufacturer, Sprague, that halogen solvent is reacting with the exposed edge foil of their capacitors. Sprague, in turn, has remedied the process by epoxy coating the exposed foil.

i TVA will centinue to monitor these power supplies in order to ensure that the implementation of the new Bailey Meter procedures is i effec tive.

i Babcock & Wilcox has furnished field change No.122 (including replacement hardware .and installation procedures). This field change

< was approved by TVA on March 23, 1981. Construction employees will

complete the implementation of field change No. 122 by March 1, 1982. .

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