ML12088A174
| ML12088A174 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 03/27/2012 |
| From: | Chalifoux R ATC Nuclear |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| 47567 | |
| Download: ML12088A174 (3) | |
Text
03/27/2012 U.S. Nuclear Regulatory Commission OperationsCenter Event Report Page I Part 21 (PAR) Event# 47567 Rep Org: ATC NUCLEAR Notification Date I Time: 01/03/2012 16:19 (EDT)
Supplier: ATC NUCLEAR Event Date I Time: 01/02/2012 07:00 (EST)
Last Modification: 03/26/2012 Region: 1 Docket #:
City: OAK RIDGE Agreement State: Yes County: License #:
State: TN NRC Notified by: R.A.CHALIFOUX Notifications: DANIEL HOLODY R1DO HQ Ops Officer: JOE O'HARA DAVID AYRES R2DO Emergency Class: NON EMERGENCY PART 21 GRP EMAIL 10 CFR Section:
21.21 (d)(3)(i) DEFECTS AND NONCOMPLIANCE PART 21 REPORT - DEFECTIVE 48 VOLT DC SAFETY RELATED POWER SUPPLIES The following was received via fax:
"ATC Nuclear has identified a design defect associated with power supplies provided through ATC Nuclear, Schenectady, NY. The defect was identified during Failure Mode Analysis following return of one of the units from the customer. The 48 VDC Power Supplies, PIN DA265A1 879P00/ST were provided as safety related components to Entergy's Pilgrim Station under Purchase Orders 10240621, 10282296 and 10308991. Entergy's Pilgrim Station is currently the only station in possession of these items. The failures are exhibited as a spurious overvoltage shutdown condition when power is applied or a spurious overvoltage shutdown condition if the overvoltage circuit becomes contaminated with particulate or other material. The design defect is related to the specific silicon control rectifier used in the over voltage protection circuit. An extent of condition review is ongoing to determine if other power supplies provided under these three purchase orders are affected. Currently none of the other power supplies provided have exhibited this condition.
"The affected serial numbers are: 90922-1, 90922-2, 90922-3, 91013-1, 91013-2, 91013-3 under purchase orders 10240621 and 10282296.
"The affected serial numbers are: 110512-1, 110512-2, 110512-3, 110512-4, 110512-5 under purchase orders 10308991.
"ATC does not have sufficient information to evaluate the safety significance of the defect because the quantities and locations of the power supplies currently in use is not known.
"Information
Contact:
Ray Chalifoux ATC Nuclear (865) 384-0124."
03/27/2012 U.S. Nuclear Regulatory Commission OperationsCenter Event Report Page 2 Part 21 (PAR) Event# 47567
- UPDATE FROM CHALIFOUX TO KLCO ON 3/26/12 AT 0841 EDT VIA FAX ***
"ATC Nuclear has identified an additional defective lot of power supplies provided through ATC Nuclear, Schenectady, NY to Xcel Energy's Monticello Station under Purchase Order #00037345. The defects were identified during Failure Mode Analysis following return of twelve units from the customer. The additional affected 115 VDC Power Supplies, P/N DA265A1313P001/ST, Serial Numbers 110713-1 through 110713-12 also were found to contain design flaws in the overvoltage protection circuitry similar to the 48 VDC power supplies. A design change was implemented to resolve the defective overvoltage protection circuit and the defects were resolved. No other additional customers are affected. The customer had not placed the power supplies into service."
Notified the R3DO (Stone) and the Part 21 Reactor Group via email.
March 26, 2012 NRC Operations Center FAX (301) 816-5151.
Subject:
UPDATE 10 CFR PART 21 N.OT-IICATION OF DEFECTIVE POWER SUPPLIES LOGRNUMBER 2012-01-00 To whom this may concern:
ATC Nuclear has identified an additional defective lot of power supplies provided through ATC Nuclear, Schenectady, NY to Xcel Energy's Monticello Station under Purchase Order #00037345. The defects were identified during Failure Mode Analysis following return of twelve units from the customer. The additional affected 115 VDC Power Supplies, P/N DA265AI313P001/ST, Serial Numbers 110713-1 through 1.10713-12 also were found to contain design flaws in the overvoltage protection circuitry similar to the 48 VDC power supplies. A design change was implemented to resolve tlhe defective overvoltage protection circuit and the defects were resolved. No other additional customers are affected. The customer had not placed the power supplies into service.
Previous Report:
ATC Nuclear has identified a design defect associated with power supplies provided through ATC Nuclear, Schenectady, NY, The defect was identified during Failure Mode Analysis following return of one of the units from the customer. The 48 VDC Power Supplies, P/N DA265A1879P001/ST were provided as safety related components to Entergy's Pilgrim Station under Purchase Orders 10240621, 10282296 and 10308991. Entergy's Pilgrim Station is currently the only station in possession of these items. The failures are exhibited as a spurious overvoltage shutdown condition when power is applied or a spurious overvoltage shutdown condition if the overvoltage circuit becomes contaminated with particulate or other mnaterial. The design defect is related to the specific silicon control rectifier used in the over voltage protection circuit An extent of condition review is ongoing to determine if other power supplies provided under these three purchase orders are affected, Currently none of the other power supplies provided have exhibited this Condition.
The affected serial numbers are:
Entergy - Pilgrim Purchase Order Serial Numbers Entergy - Pilgrim Purchase Order Serial Numbers 10240621 and 10282296 10308991 90922-1 110512-1, 90922-2 110512-2 90922-3 110512-3 91013-1 110512-4 91013-2 '110512-5 91013-3 ATC does not have sufficient information to evaluate the safety significance of the defect because the quantities and locations of the power supplies currently in use are not known.
Contact Ray Cbalifoux ATC Nuclear 865 384 0324 InrfoMation Sincevly, iAL Un1ii vice president QA, AIC NUClea