ENS 51923
ENS Event | |
|---|---|
05:00 May 10, 2016 | |
| Title | Part 21 - Initial Notification of Masterpact Breaker Fail to Close |
| Event Description | The following information was a licensee received facsimile;
Pursuant to 10CFR 21.21(d)(3)(ii), AZZ/NLI is providing written notification of the identification of a potential defect or failure to comply. On the basis of our evaluation, it has been determined that there is sufficient information to determine if the subject condition is left uncorrected could potentially create a Substantial Safety Hazard or could create a Technical Specification Safety Limit violation as it relates to the subject plant applications. The plants will need to evaluate their application to determine if the identified condition could have an impact to the plant operation. The following information is required per 10CFR 21.21(d)(4): (i) Name and address of the individual or individuals informing the Commission. Tracy Bolt, Director of Quality Assurance Nuclear Logistics, Inc. 7410 Pebble Drive Ft. Worth, TX 76118 (ii) Identification of the facility, activity, or the basic component supplied for such facility or such activity within the United States which fails to comply or contains a defect. Masterpact NT and NW style circuit breakers. -The failure of the breaker being ready to electrically close after being subjected to an 'Anti-Pump condition'. Note: The specific application where the failures have occurred is when the breaker is being utilized as a starter for closing into an inductive load like a fan motor. (iii) Identification of the firm constructing or supplying the basic component which fails to comply or contains a defect. AZZ/ Nuclear Logistics Fort Worth, Texas 76118 (iv) Nature of defect or failure to comply and the safety hazard which is created or could be created by such defect or failure to comply. Possible 'failure to close' condition of Masterpact breakers NT and NW style, that are being used with specific logic schemes that are subjected to 'anti-pump' conditions during normal operation. These breakers have a higher susceptibility to not return to the ready to close position after the close signal has been removed. PSEG reported approximately 14 instances with different breakers in different cubicles where they initiated an electric close order, and the breakers failed to close. All of the 14 instances were in applications of being used to start an inductive load. NLI inspected three of the breakers (all NWs) that were returned by PSEG and could not fully replicate the problem as described by the plant. NLI was only able to repeat the failure to close when performing an 'anti-pump' test. The failure to close was intermittent, but could be duplicated. When the anti-pump condition was not present, NLI could not duplicate a failure to close. Visual inspections of the tested breakers did not reveal any visible damage to the breaker linkages, latches, shunt close or shunt trip assemblies. Schneider Electric (SE) performed testing of three Masterpact NW08 breakers (operated to beyond design life) and duplicated the fail to close condition as described by the plant. It was determined that a standing close signal with a trip/open signal applied is determined to be the root cause of the fail to close issue. The SE testing confirms that the presence of this condition can cause the breaker anti-pump latch to receive excessive forward pressure. When the nose of the latch impacts the close coil plunger, it will 'rock' up in the rear, catching on the top of the mechanism plate. Once the close voltage is removed, and the plunger retracts, the latch may or may not let go. If the latch does not release, then application of the close coil voltage will simply activate the close coil plunger and without the latch underneath the plunger, the breaker will not close. PSEG performed extensive troubleshooting at the Hope Creek plant and discovered that all of the affected breakers were in an anti-pump condition when the breakers failed to close. (v) The date on which the information of such defect or failure to comply was obtained. This revised notification is being submitted based on the information gathered on 5/10/2016 after additional testing, at the request of River Bend, was performed. This additional testing was requested following the notification that was provided to the plants listed below, in the original issue of this letter in February 2016. The evaluation of the condition was originally completed in September of 2012. The issue was originally determined at that time to not be a reportable condition based on the breaker not containing a defect and the condition was believed to be attributed to the specific logic scheme at the plant. To date, this issue has only been reported to NLI from the following plants, PSEG Hope Creek and River Bend Station. No other plants have reported this specific fail to close condition. NLI was in direct communication with the plants when this issue was first being evaluated and the failure analysis were being conducted. The two affected plants were knowledgeable of the condition. (vi) In the case of a basic component which contains a defect or fails to comply, the number and location of these components in use at, supplied for being supplied for, or may be supplied for, manufactured or being manufactured for one or more facilities or activities subject to the regulations In this part. Plants which have been supplied the Masterpact circuit breakers. PSEG Hope Creek - Issue Identified for NW style River Bend - Issue identified for NT style Callaway - This issue has not been identified however, the potential should be evaluated. St. Lucie - This issue has not been identified however. the potential should be evaluated. Turkey Point - This issue has not been identified however, the potential should be evaluated. Beaver Valley - This issue has not been identified however, the potential should be evaluated. Davis Besse - This issue has not been identified however, the potential should be evaluated. Three Mile Island - This issue has not been identified however, the potential should be evaluated. Calvert Cliffs - This issue has not been identified however, the potential should be evaluated. Hatch -This issue has not been identified however, the potential should be evaluated. STP - This issue has not been identified however, the potential should be evaluated. SONGS - This issue has not been identified however, the potential should be evaluated. KHNP Ulchin - This issue has not been identified however, the potential should be evaluated. KHNP Kori - This issue has not been identified however, the potential should be evaluated. Duke Oconee - This issue has not been identified however, the potential should be evaluated. Duke McGuire - Non-safety (not supplied by NU), This issue has not been identified. (vii) The corrective action which bas been, is being, or will be taken; the name of the individual or organization responsible for the action; and the length of time that has been or will be taken to complete the action. NLI originally created a technical bulletin to address the issue and recommendations. However, since new information has been recently identified, NLI TB-12-007 will be revised, as the proposed solution will not reliably solve the problem for all postulated events. Upon completion of the revised technical bulletin, it will be re-submitted to the plants which have been supplied the Masterpact breakers from NLI. (viii) Any advice related to the defect or failure to comply about the facility, activity, or basic component that has been, is being, or will be given to purchasers or licensees. NLI is currently working with the OEM of the circuit breaker to determine the permanent solution to correct the possible failure to close event after the breaker is subjected to an Anti-Pump condition. Advice for plants with breakers currently installed: Evaluate the applications where the breakers may be potentially subjected to an Anti-Pump condition; where the close coil will be energized for an extended period of time. The circuit breaker will continue to operate if this condition is present however there may need to be human interaction with the circuit breaker by manually pressing the trip/open button on the front of the circuit breaker to free the mechanism. Please contact NLI with any questions or comments. Sincerely, Tracy Bolt Director of Quality Assurance
Added 4 additional plants that were inadvertently left off the list. Browns Ferry - This issue has not been identified however, the potential should be evaluated. Fort Calhoun - This issue has not been identified however, the potential should be evaluated. Wolf Creek - This issue has not been identified however, the potential should be evaluated. Seabrook - This issue has not been identified however, the potential should be evaluated. Notified R1DO (Burritt), R2DO (Heisserer), R3DO (Duncan), R4DO (Campbell), and Part 21 Group via email.
The following information was received via facsimile: Additional information in attachment has been updated since the original report provided on 5/13/2016. Additional facility identified as impacted: St. Lucie - Issue identified For additional information contact: Tracy Bolt Director of Quality Assurance AZZ/NLI Nuclear Logistics 7410 Pebble Drive Fort Worth, Texas 76118 Notified the R1DO (Ferdas), R2DO (Rich), R3DO (Kunowski), R4DO (Gaddy) and Part 21 Reactor group (via email).
On the basis of our evaluation, it has been determined that there is sufficient information to determine if the subject condition is left uncorrected could potentially create a Substantial Safety Hazard or could create a Technical Specification Safety Limit violation as it relates to the subject plant applications. The plants will need to evaluate their application to determine if the identified condition could have an impact to the plant operation. Plants which have been supplied the Masterpact circuit breakers: PSEG Hope Creek - Issue Identified for NW style River Bend - Issue identified for NT style Callaway - This issue has not been identified however, the potential should be evaluated. St. Lucie - This issue has been identified. Turkey Point - This issue has not been identified however, the potential should be evaluated. Beaver Valley - This issue has not been identified however, the potential should be evaluated. Davis Besse - This issue has not been identified however, the potential should be evaluated. Three Mile Island - This issue has not been identified however, the potential should be evaluated. Calvert Cliffs - This issue has not been identified however, the potential should be evaluated. Hatch - This issue has not been identified however, the potential should be evaluated. STP - This issue has not been identified however, the potential should be evaluated. SONGS - This issue has not been identified however, the potential should be evaluated. KHNP Ulchin - This issue has not been identified however, the potential should be evaluated. KHNP Kori - This issue has not been identified however, the potential should be evaluated. Duke Oconee - This issue has not been identified however, the potential should be evaluated. Duke McGuire - Non-safety (not supplied by NLI). This issue has not been identified. Browns Ferry - This issue has not been identified however, the potential should be evaluated. Fort Calhoun - This issue has not been identified however, the potential should be evaluated. Wolf Creek This issue has not been identified however, the potential should be evaluated. Seabrook This issue has not been identified however, the potential should be evaluated. NLI originally created a technical bulletin to address the issue and recommendations. However, since new information has been recently identified, NLI TB-12-007 has been revised. The solution for this potential problem is to replace the XF (shunt close assembly) with the XFCOM shunt close assembly. The part numbers are: 847323 (100-130VAC/DC) 847324 (200-240VAC/DC) Additional details regarding the replacement device are contained in the NLI technical bulletin TB-12-007. Notified the R1DO (Krohn), R2DO (Blamey), R3DO (Jeffers), R4DO (Deese) and Part 21 Reactor group (via email). |
| Where | |
|---|---|
| Azz - Nuclear Logistics, Inc. Fort Worth, Texas (NRC Region 4) | |
| Organization: | Azz - Nuclear Logistics, Inc. |
| Reporting | |
| 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
| Time - Person (Reporting Time:+62.38 h2.599 days <br />0.371 weeks <br />0.0854 months <br />) | |
| Opened: | Tracy Bolt 19:23 May 12, 2016 |
| NRC Officer: | Vince Klco |
| Last Updated: | Sep 22, 2016 |
| 51923 - NRC Website | |
Azz - Nuclear Logistics, Inc. with 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
WEEKMONTHYEARENS 519232016-05-10T05:00:00010 May 2016 05:00:00
[Table view]10 CFR 21.21(d)(3)(i), Failure to Comply or Defect Part 21 - Initial Notification of Masterpact Breaker Fail to Close 2016-05-10T05:00:00 | |