ML19209A546

Discusses 790828 Rept Submitted Re Inadequate Range of Fault Current Protection on Some Containment Electrical Power Penetrations.Circuit Mods in Progress.Final Rept Will Follow Upon Mod Completion

ML19209A546
Person / Time
Site:	North Anna
Issue date:	09/27/1979
From:	Brown S VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
NUDOCS 7910040304
Download: ML19209A546 (1)

Text

Vepco_ _ . _ _ _ _ _ . _

September 27, 1979 Mr. James P. O'Reilly, Director Serial No. 717A Office of Inspection & Enforcement PSE&C/JMD:adw:me U.S. Nucle:r Regulatory Comission Region II Docket No. 50-339 101 Marietta Street, Suite 3100 Atlanta, Georgia 30303

Dear Mr. O'Reilly:

On August 28, 1979, a report was made under the provisions of 10CFR50.55(e) concerning an inadaquate range of fault current pro-tection on some containment electrical power penetrations.

During a review of the containment electrical power penetration fault current protection, it was discovered that some of the penetra-tion limits are not co-ordinated with the protection device curves throughout the full range of potential faults.

We have completed the review of all power circuits utilizing containment electrical penetrations and determined the revision or modification necessary to ensure protection of the penetrations for the full range of potential fault currents. There are approximately eighty (80) circuits that require one of the following)for complete protection:

1) adjust setting of de-energize circuit during plant operation, 3)prote , tion relays, 2 rep 1.tce starter overload relay and contactor with larger size, 4) add breaker to circuit, 5) double up penetration feed-thru conductors, or 6) add fuse to ex' sting cir-cuit.Work is presently in progress on several of the circuit modifi-cations. A firm completion date is not available due to as yet in-complete material delivery schedules. Completion is estimated by November 1, 1979.

This letter is an interim report on this subject and a final report will be submitted when the corrective action is complete.

If additional information is required for your review, please notify us.7ery' truly yours,;

,/l/-._ SNT.' Brown, ~ J r'."~Senior Vice President-Power Station gk Engineering and Construction 1()'1036 Mr. Victor Stallo, Dit >ctor Office of Inspection & Enforcement Mr. Harold R. Denton, Director y t Office of Nuclear Reactor Regulation

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