ML18139A546

Forwards Response to IE Bulletin 80-20.Westinghouse Type W-2 Control Switch Applications Found.Subj Switches Have Been Tested Satisfactorily

ML18139A546
Person / Time
Site:	Surry, North Anna
Issue date:	09/15/1980
From:	Sylvia B VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
690, IEB-80-20, NUDOCS 8009300116
Download: ML18139A546 (3)

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VIRGINIA ELECTRIC AN>> PowER CoMPA.NY

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. RICHXOND,VIBGIN.IA 23261 September 15, 1980 JD SEP 17 Mr. James P. O'Reilly, Director Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, Suite 3100 Atlanta;G~~rgia 30303

SUBJECT:

I.E. BULLETIN 80-20 This is in response to I. E.Bulletin 80-20, "Failures of Westinghouse Type W-2 Spring Return to Neutral Control Switches".* Our responses for Surry Power Station Unit Nos: 1 and 2 and North Anna Power Station Unit Nos. 1 and.2 are attached.

If you have any questions or require additional information, please contact this office.

Very tru~y yours, Pf.~.

Manager - Nuclear Operations and Maintenance Attachment cc: Director, Division of Reactor Operations Inspection O~fice of Inspection and Enforcement U.S. Nuclear Regulatory Commission Mr. Steven A. Varga, Chief Operating Reactors Branch No. l Division of Licensing Mr. Robert A. Clark, Chief

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Operating Reactor Branch No. 3 Division of Licensing _./ V aoo93 00 11,

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r e e Attachment Page 1 r'

I SURRY POWER STATION RESPONSE TO IE BULLETIN 80 "FAILURE OF WESTINGHOUSE TYPE W-2 SPRING RETURN TO NEUTRAL CONTROL' SWITCHES" Upon review, it was found that there are five Westinghouse Type W-2 switches with the .'"-spring-return-to-neutral" feature on each unit at Surry. None of these switches are in control circuits for safety-related applications.

Prior to a determination of the safety relationship of the switches, the test-ing as prescribed by paragraph 2 of IEB 80-20 was carried out. No failures were found.

As requested by the forwarding letter, the manpower expended in conducting the reviews and testing to support this response was 52 man-hours.

.. f e e Attachment Page 2 RESPONSE TO IE BULLETIN 80-20 NORTH AN~A UNITS 1 AND 2

1. A review of the North Anna Unit 'l 'and 2 design was made for sa.fety related applications utilizing Westinghouse Electric Corporation Type W-2 control switches with spring-return-to-neutral switch action. The following applications were identified:

- Reactor Protection System manual trip switch - 2 switches pe.r unit.

- Re~'ctor Protection System trip reset* switch - 2 switches per unit.

- Emergency diesel generator governor control switch - 2 switches per unit.

- Emergency diesel generator voltage control switch - 2 switches per unit.

Although the above functions utilize W-2 switches with spring-return-to-neutral action, the design of the circuits is not of the type described in the Bulletin.

The* Reactor Protection System trip and reset control switches have no automatic safety related functions via neutral contacts. Reactor protec-tion automatic signals actuate an undervoltage device which is separate from the control switches. The emergency diesel generator governor control and voltage control switches have no automatic control through the neutral contacts.

2. Before a final determination was made concerning the applicability of all station W-2 switches, continuity tests were conducted as a precautionary measure. In addition to the switches listed above, other W-2 spring-return switches utilized in non-safety related applications were tested.

These applications included: steam dump mode selector switch, steam dump control switches, makeup control switch, and the pilot wire test switches.

The neutral contacts for all switches tested were found to be in the correct position.

3. Since no applications of W-2 switches as described in this Bulletin were found at North Anna, no long term corrective measures are planned ..

4. The Bulletin requests an estimate of manpower expended to review the concerns of the Bulletin and preparation of the report.

- Research W-2 switch applications - 2 man days

- Continuity testing of W-2 switch applications - 3 man days

- Preparation of report - 1/2 man day