ENS 56821
ENS Event | |
|---|---|
07:00 Aug 30, 2023 | |
| Title | Part 21 - Inconsistent Potentiometer Resistance Values |
| Event Description | The following is a synopsis of information that was provided by Curtiss-Wright via fax:
On August 30, 2023, Enertech (a division of Curtiss-Wright) determined a potential defect for potentiometer part number D2060S based on the inspection of a returned items from Korea Hydro and Electro Power in Korea. A number of returned potentiometers exhibited inconsistent resistance values at certain stroke positions. The potentiometers are used in modulating actuators. A shorter wiper was used in the manufacture of the potentiometers that introduced the possibility of intermittent separation between the wiper (sliding contact) and the coil at certain stroke positions, resulting in momentary signal interruptions. The evaluation at Enertech is also ongoing regarding the potential effects of wiper separation on the functionality of the modulating actuator and will not be completed within 60 days. The expected date of completion is December 20, 2023. South Texas Project Electric Generating Station (Operator: STP Nuclear Operating Company) purchased defective modulating actuators on four occasions. Questions should be directed to Loretta Anaya, Quality Assurance Manager, Enertech, at 714-982-1856. Known potentially affected plant(s): South Texas Project
Enertech has completed their evaluation of the deviation described in their interim report submitted on 27 October, 2023, and concluded that the deviation does not potentially create a substantial safety hazard. Notified R4DO (Dixon) and Part 21 Group (Email) |
| Where | |
|---|---|
| Curtiss Wright Flow Control Co. Brea, California (NRC Region 4) | |
| Organization: | Curtiss Wright Flow Control Co. |
| Reporting | |
| 10 CFR 21.21(a)(2), Interim Report for Comply or Defect in Component | |
| Time - Person (Reporting Time:+1405.95 h58.581 days <br />8.369 weeks <br />1.926 months <br />) | |
| Opened: | Loretta Anaya 20:57 Oct 27, 2023 |
| NRC Officer: | Lawrence Criscione |
| Last Updated: | Dec 7, 2023 |
| 56821 - NRC Website | |
Curtiss Wright Flow Control Co. with 10 CFR 21.21(a)(2), Interim Report for Comply or Defect in Component | |
WEEKMONTHYEARENS 578272025-05-21T04:00:00021 May 2025 04:00:00
[Table view]10 CFR 21.21(a)(2), Interim Report for Comply or Defect in Component Part 21 Interim Report of Deviation ENS 575992025-01-07T04:00:0007 January 2025 04:00:00 10 CFR 21.21(a)(2), Interim Report for Comply or Defect in Component Part 21 Interim Report of Deviation ENS 568212023-08-30T07:00:00030 August 2023 07:00:00 10 CFR 21.21(a)(2), Interim Report for Comply or Defect in Component Part 21 - Inconsistent Potentiometer Resistance Values ENS 566832023-06-22T04:00:00022 June 2023 04:00:00 10 CFR 21.21(a)(2), Interim Report for Comply or Defect in Component Part 21 Interim Report - Failure of Curtiss Wright Supplied Safety Related Relay ENS 559602022-04-24T04:00:00024 April 2022 04:00:00 10 CFR 21.21(a)(2), Interim Report for Comply or Defect in Component Part 21 Report - Potential Defect in Quick Disconnect Connector Cable Assemblies ENS 509002015-03-17T04:00:00017 March 2015 04:00:00 10 CFR 21.21(a)(2), Interim Report for Comply or Defect in Component Interim Part 21 Report - Potential Test Induced Defect in a 0867F Main Steam Safety Relief Valves ENS 489962013-05-03T04:00:0003 May 2013 04:00:00 10 CFR 21.21(a)(2), Interim Report for Comply or Defect in Component Interim Part 21 Report of Potential Defect in a Relief Valve Bellows 2025-05-21T04:00:00 | |