ML17286A024
| ML17286A024 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 10/11/2017 |
| From: | Toomey M National Technical Systems |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML17286A024 (1) | |
Text
- -----
NTS October 11, 2017 Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
Subject:
Dear Sirs,
Part 21 on Siemens 5-3AF-GER-350-1200-78 & 5-3AF-GEU-350-1200-78 Circuit Breakers Pursuant to the requirements of 10 CFR Part 21, this letter is hereby provided to you as notification of a Part 21 condition. The subject equipment are Siemens Types 5-3AF-GER-350-1200-78 and 5-3AF-GEU-350-1200-78 Medium Voltage Circuit Breakers that NTS has dedicated for use as a basic component. NTS has supplied these circuit breakers to Entergy - Arkansas Nuclear One only. The Circuit Breakers have experienced a failure to close condition as a result of degraded Siemens 40-901-495-003 yellow closing springs. These models of circuit breakers were manufactured during the limited timeframe of 1996-2000 and utilize Westinghouse/Cutler-Hammer WL-3558 vacuum interrupters paired with the yellow closing spring. This is the only combination that has exhibited a failure to close condition after approximately 20 years.
NTS/Siemens recommends replacement of the yellow closing spring with Siemens 18-763-442-252 yellow/red closing springs.
Thank you and if you have any questions, please contact NTS' Senior Director of Nuclear Engineering and Test Services, Tom Brewington at (256) 716-4512 or email at tom.brewington@nts.com.
Sincerely,
~--~... ---~--- *-
Megan Toomey Sr. Contracts Manager NTS Huntsville NTS Huntsville
- 7800 Highway 20 West
- Huntsville, AL 35806 * (256) 837*4411
- Fax: (256) 830*2109
- www.nts.com