ML19208B230

Deficiency Rept:On 790828,review Indicated Feeder Breaker Trip Curves to Some Penetrations Not Coordinated W/Penetration Limits.Settings for Proper Penetration Protection Limits Are Being Revised

ML19208B230
Person / Time
Site:	North Anna
Issue date:	08/31/1979
From:	Brown S VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
References
REF-PT21-79-148-000 717, NUDOCS 7909190379
Download: ML19208B230 (2)

Text

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Vepco VIRGINI A ELECTRIC AND PCWER CCMP ANY, RICHMONO. VIRGING A 23261 August 31, 1979 Mr. James P. O'Reilly, Director Serial No. 717 Office of Inspection & Enforcement PSE&C/JMD:mac: wang U. S. Nuclear Regulatory Comission Region II Docket Nc. 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 inadequate range of fault current protection on some containment electrical penetrations.

In accordance with the reporting requirements of 10CFR21, the following

, information is submitted:

A. Name and address of reporting individual:

Mr. E. A. Baum, Executive Manager Licensing and Quality Assurance Virginia Electric and Power Company P. O. Box 26666 Richmond, Virginia 23261

8. Facility, activity, and/or component affected:

North Anna Power Station, Unit 2 Conax Containment Electrical Penetrations Klockner-Moeller Motor Control Centers Various Vendors - Molded Case Circuit Breakers C. Name of firm constructing the f acility or supplying the component, activity or service:

Conax Containment Electrical Penetrations q 7 ly Klockner-Moeller Motor Control Centers Various Vendors - Molded Case Circuit Breakers

0. Description of defect, deficiency, or failure to comply: g It was discovered during a review of the containment electrical penetration f ault current protection, that the feeder breaker trip curves to some of the penetrations are not co-ordinated with the penetration limits throughout the full range of potential faults.

The unprotected area generally occurs for intermediate faults or overloads slightly beyond the continuous rating of the penetration.

7 909190 37jF'

~

Mr. James P. O'Reilly, Director <

E'. Date of determination of reportability:

August 28, 1979 F. Similar components, activities, or services:

North Anna Unit 1 G. Corrective action which has been, is being or will be taken, the individual responsible and the length of time to complete the action:

Vepco and Stone & Webster are comparing all power penetration limit curves to the breaker protection curves and determining the revised settings or change of breakers necessary to obtain the required range for setting proper penetration protection limits. The completion date for all required action has not yet been determined and will be supplied at a later date.

H. Othe: information:

None Any information not available at this time will be submitted in a follow-up letter as a 30-day report.

Should you require further inform ion, please contact this office.

/ Ve' ul y r

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Seni ic President - Power Stat ~o Engine ring and Construction cc: Director, Office of Inspection and Enforcement (3)

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