ML12005A231

Notification of Potential Part 21 Report - Defective 48 Volt DC Safety Related Power Supplies

ML12005A231
Person / Time
Site:	Pilgrim
Issue date:	01/03/2012
From:	Chalifoux R ATC Nuclear
To:	Office of Nuclear Reactor Regulation
References
Download: ML12005A231 (3)

Text

0110312012 U.S. Nuclear Regulatory Commission OperationsCenter Event Report Pa,-e I Part 21 (PAR) Event# 47567 Rep Org: ATC NUCLEAR Notification Date / Time: 01/03/2012 16:19 (EST)

Supplier: ATC NUCLEAR Event Date I Time: 01/02/2012 07:00 (EST)

Last Modification: 01/03/2012 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 UNSPECIFIED PARAGRAPH 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 DA265A1879P00/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."

01/03/2012 U.S. NuclearRegulatory Commission OperationsCenter Event Report Page2 Part 21 (PAR) Event# 47567

Received at: 01/03/2012 16:17 01/03/2012 16:14 8656755399 ATC NUCLEAR TN PAGE 01/01 January 2, 2012 NRC Operations Center FAX (301) 816-5151

Subject:

10 CFR PART 21 NOTiIFCATION OF DEFECTIVE POWER SUPPLIES To wbom this may concern:

This notification is in accordance with U.S. Nuclear Regulatory Regulation 10 CFR 21 ATC Nuclear has identified a design defect assbeiated 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 DA265A1 879P00 l/ST were provided as safety related components to Entergy's Pilgrim Station under Purchase Orders 10240621, 10282296 and 1.0308991.

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:

Entergy - Pilgrim Purchase Order Serial Numbers Entergy - Pilgrim Purchase Order Serial Numbers 10240621 and 10282296 1.0308991 90922-1 1.10512-1 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 deffect because the quantities and locations of the power supplies currently in use is not known.

Information

Contact:

Ray Chalifoux ATC Nuclear 865 384 01.24 Sincerely, Vi4 A. Ch TNeifoux Vice President QA, ATC Nuclear