ML19210D772

Responds to IE Bulletin 79-23 Re Failure of Emergency Transformers.No Connections Made Between Low Kva Rated Transformers & High Kva Emergency Diesel Generators W/O Limitations on Flow of Circulatory Currents

ML19210D772
Person / Time
Site:	Perkins, Cherokee
Issue date:	11/02/1979
From:	Dail L DUKE POWER CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
IEB-79-23, NUDOCS 7911280045
Download: ML19210D772 (1)

Text

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DUKE POWER COMPANY

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ELEcTIcic CENTEtt Box 33189, CarrittoTTE, N. C. 2M242 od'! "

.  % :3 November 2, 1979 h, Mr. J. P. O'Reilly, Director U.S. Nuclear Regulatory Commission -

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101 thrietta Street, Suite 3100 Atlanta, Georgia 30303 Re: Cherokee Nuclear Station Docket Nos.: 50-491,492 & 493 Perkins Nucle Station Docket Nos.: 0-488, 489, 490 IE Bulletin 7 44

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Duke File: P81-1412-11-1

Dear Mr. " Reilly:

In response to your letter of September 12, 1979, which transmitted Nuclear Regulatory Commission IE Bulletin 79-23, Duke has conducted a review of the design for Cherokee and Perkins Nuclear Stations. This review has revealed that connections have not been made between low KVA rated transformers and high KVA EDG's without adequate limitations on the flow of circulatory currents at these stations. The diesel generator factory test for Cherokee, 22 hours2.546296e-4 days <br />0.00611 hours <br />3.637566e-5 weeks <br />8.371e-6 months <br /> at full load and 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> at 110% load, is expected to be complete with results available April 1,1983. The tests for Perkins have not been scheduled as of this date.

Very truly yours, vd.

.D 1403 ?S8 L.C. Dail, Vice-President Design Engineering EKM/ cam 7 911280 0 K Wc f/