ML19095A445

Response to IE Bulletin Nos. 77-05,77-05A, & NRC Letter of 11/18/1977, Enclosed Study Results Regarding Environmental Qualifications of Electrical Connectors

ML19095A445
Person / Time
Site:	Surry
Issue date:	12/07/1977
From:	Stallings C Virginia Electric & Power Co (VEPCO)
To:	O'Reilly J NRC/RGN-II
References
IEB-77-005, IEB-77-005A, Serial No. 529/111877
Download: ML19095A445 (3)

Text

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VIRGINIA ELEC:'i:RIC .A.ND POWER *coMPAN~-.' si'

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• RIOHMOND,VIRGINI.A 23261 .. *:*

• oecember7; 1977 Mr. James -P. O'Reilly, Director Serial No.** 529/111877 Office of Inspection and Enforcement LQA/JEE:jal *.

u. s. Nuclear Regulatory* Commission Region II

• Docket Nose 50-280 230 Peachtree St~eet, Northwest 50-281 Atlanta, Georgia 30303 *

Dear Mr. O'Reiily:

Thi~ letter is in response to IE l3ulletin Nos*. 77-05 and* 77-0SA and Mr. Case's letter' of November 18, 1977*, concerning environmental

_qualifications of elect~ical connectors subject to an accident environ-ment and are required to be operable during an accident. A_ s1;:udy has

• been conducted and we have.found that the.only electrical con~ectors required for safety are the channels needed for reactor trip during a LOCA - low pressurizer level and low pressurizer pressure. .These channels would actuate a reactor .a~d turbine trip within the first a~conda well before accident .radiation levels are.reached or the commencement of caustic sprays. therefore, these connectors (manufactured.by Amphenol)'

• w~uld not be exposed to high radiation or caustic sprays before their function was completed.*

on* November 16, 1977, our Messrs. W'" F. Bennett-and J.M .. Davis met with Messrs. T. A~ Ippolito and M*. B. Fairtile when test results on the Amphenol connectors for accident steam. temperature, and pressure conditions .were present'ed~

• The staff found the* results acceptable. A

_ brief description of _the test is attached.

• It is our conclusion .that no other electrical connectors inside or outside the containment would be required to function. during an accident.**

The Amphenol Connectors .described abiove-.will not be required to operate -

beyond the first seconds into_the accident before further degradation of the containment environment and would not compromise the-operation of safety-related equipment.. * *

. Very *truly yours, .

. _Zp_ )/)?. \,dl/dh;~ 7r

• C. M*. Stallings

• Vice President-Power Supply and Production Operations Attachment

• cc: Mr .. Robert w. Reid/

j d

e e DESCRIPTION OF TEST Amphenol Connectors used at Surry Units 1 and 2:

1. 280°F at 60 psia for 60 min.

2~ 140-150°F at atmospheric for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

RESULTS: Insulation Resistance never fell below 34.SM~.

't.~ **

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