ML20081C761
| ML20081C761 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 03/05/1984 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NUDOCS 8403150007 | |
| Download: ML20081C761 (2) | |
Text
e, TENNESSEE VALLEY AUTHORITY CH ATTANOOGA. TENNESSEE 37401 400 Chestnut Street Tower II 34 MAR 12 P l : 07 March 5,1984 BLRD-50-439/84-15 U.S. Nuclear Regulatory Commission Region II Attn:
Mr. James P. O'Reilly, Regional Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30303
Dear Mr. O'Reilly:
BELLEFONTE NUCLEAR PLANT UNIT 2 - DEFECTIVE AMPLIFIERS IN SAFETY-RELATED PANELS MANUFACTURED BY EL-TEX - BLRD-50-439/84 FIRST INTERIM REPORT The subject deficiency was initially mported to NRC-0IE Inspector P. E. Fredrickson on February 14, 198 4 in accordance with 10 CFR 50.55(e) as NCR 2815. Enclosed is.our first interim report. We expect to submit our next report by July 6,1984. The applicability of 10 CFR Part 21 to this deficiency will be determined at a later date.
If you have any questions, please get in touch with R. H. Shell at FTS 858-2688.
Very truly yours, TENNESSEE VALLEY AUTHORITY
@)llVM L. M. Mills, Manager Nuclear Licensing Enclosure cc:
Mr. Richard C. DeYoung, Director (Enclosure)
Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.
20555 Records Center (Enclosure)
Institute of Nuclear Power Operations 1100 circle 75 Parkway, Suite B00 Atlanta, Georgia 30339 g3150007840305 OFFICIAL COPY S
ADOCK 05000439 PDR gh 2]
1983-TVA SOTH ANNIVERSARY
' An Equal Opportunity Employer
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ENCLOSURE BELLEFONTE NUCLEAR PLANT UNIT 2 DEFECTIVE AMPLIFIERS IN SAFETY-RELATED PANELS MANUFACTURED BY EL-TEX l
BLRD-50-439/84-15
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NCR 2815 10 CFR 50.55(e)
FIRST INTERIM REPORT Description of Deficiency All DC isolation amplifiers in electrical panels 2EU-EDP-52A-E and 2EU-EDP-51A-E were found to be defective. These amplifiers are powered by a 125V AC supply, and send a 0-3 milliamp (ma) signal to the main control room indicators which show the status of the class 1E 125V DC power distribution system. This system provides power to various essential safety-related switches such as the 6.9 kV,13.8 kV, and 480V switchgear.
The failure of the amplifiers has resulted in a wide open (i.e., maximum 3 ma) output to the indicators, regardless of the input signal. Tais reaults in erroneous indications in the control room on the status of the 125V DC system.
Interim Progress TVA is still investigating the cause of this ' deficiency. The recommended corrective action has been to remove and replace the defective amplifiers.
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