ML19332D365
| ML19332D365 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 11/28/1989 |
| From: | Michael Ray TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-80-20, NUDOCS 8912010076 | |
| Download: ML19332D365 (2) | |
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' TENNESSEE VALLEY AUTHORITY -
CHATTANOOGA, TENNESSEE 3740i 5N 1578 Lookout Place:
'I NOV 281988-e
- U.S.. Nuclear Regulatory Commisston ATTN
- Document Control' Desk Washington, D.C 4 20555 Jl b
Gentlemen:
In the Matter of
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Docket Nos. 50-327 Tennessee Valley Authority-
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50-328-SEQUOYAH NUCLEAR PLANT (SQN)'
IELBULLETIN 80-20,-FAILURES OF WESTINGHOUSE h
TYPE W-2 SPRING RETURN TO NEUTRAL CONTROL SWITCHES
.This submittal provides a revised response to IE Bulletin 80-20 for SON Units 1 and 2.
s TVA has completed a. review and has identifled 444 Westinghouse Electric Corporation H-2 switches originally installed at SQN.
The switches are listed and the evaluation results documented in Calculation SQN-El-008.
,Eight of the 444 W-2= switches have been replaced by Electro Switch Corporation's Electroswitch units, which do not exhibit the problem.
For 106
..of the switches with Indicating lights, the circuits have been wired to monitor contact continuity in the spring-return-to-neutral position.
The
- lights were wired in series with the switches and are energized when the switch spring. returns to the neutral position.
The remaining 330 W-2 switches
. at SON require no-modification.
These switches are acceptable without modification because one of the following four conditions applies:
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The switch is not used to perform any function necessary for. safe shutdown 7
of the plant.
2.
The controlled device will go to its safety position or there is an alternate actuation if the neutral-switch position contact failed to close upon spring. return.
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3.
The. neutral position contacts are not used to' perform a function required for_ safe shutdown.
'4. LThe switch is required by procedure to be manually verified / actuated when
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It is necessary to perform its safety-related function.
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8912010076 891128
{DR ADOCK 05000327 PDC
,g An Equal opportunity Employer i
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e.. NOV 281989 U(S.NuclearRegulatoryCommission No commitmenlis are contained in this' submittal. Please direct questions concerning this-issue to Kathy S. Whitaker at (615) 843-7748.
Very-truly yours, TENNESSEE VALLEY AUTHORITY N
Managec)_ Nucle 1 ensing and Regulatory Affairs
-cc:.Ms.S.'C. Black,NssistantDirector for Projects.
TVA Projects Division
.U.S. Nuclear Regulatory Commission One White Flint,. North
'11555 Rockville Pike Rockville, Maryland 20852 7
Mr. B. A. Wilson, Assistant Director for.. Inspection Programs TVA-Projects' Division U.S. Nuclear Regulatory Commission
-Region II-101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 NRC Resident Inspector
.Sequoyah Nuclear Plant 2600 Igou Ferry Road Soddy Daisy,' Tennessee 37379
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