ENS 47326
ENS Event | |
|---|---|
04:00 Oct 6, 2011 | |
| Title | Part 21 Notification Concerning Moore Process Controllers |
| Event Description | The following information was received from ATC Nuclear via facsimile:
This notification is in accordance with U.S. Nuclear Regulatory Regulation 10 CFR 21.21(a)(3)(ii)(b). Exelon Corporation Clinton and LaSalle Stations have identified common mode failures associated with Moore 535 Controllers (Part Number 535-000000HOST-SSTRV) provided through ATC Nuclear Tennessee. These items were provided as safety related components to Exelon under Clinton Purchase Order 00461980 and LaSalle Purchase Order 00462363. All safety related failures to date appear to originate from these specific purchase orders. The failures have been evaluated with the original equipment manufacturer and appear to be isolated to controllers containing a main processor board containing 'Revision F' labeling manufactured in early 2010 (Date Code 1310). These items all passed an extended burn-in during testing. The failures may manifest themselves as process variable (PV) drift, controller reset with loss of controller function, or create nuisance alarm conditions after a relatively short period (less than 1 year) following installation. Because the end-use application of each item is not known by ATC Nuclear, the safety hazard evaluation has been deferred to the customer. The Licensees above have been formally notified of the defect.
A failure analysis has been concluded to determine the causes for Moore Industries International (MII) 535 Single Loop Process (SLP) Controller failures, initially reported October 6, 2011 and provided by ATC Nuclear, Oak Ridge, TN. The original failure symptoms were reported to be process variable (PV) drift, controller reset with loss of controller function, or create nuisance alarm conditions after a relatively short period (<1 year) following installation. These controllers passed all Method 1 Testing including an extended burn-in to monitor for early life failure. Initial investigation isolated the failure to the controller MPU [Micro-Processing Unit] Board and identified the cause as 'Indeterminate.' Completion of a rigorous analysis by the OEM [Original Equipment Manufacturer] and ATC Nuclear has identified the failures are the result of the introduction of a 3 vDC SRAM Chip P/N CY62256VNLL-70SNXI on the MPU by Moore Industries International in 2010 which is not compatible with the 5vDC circuit. Operation of the 3V part at 5V reduces reliability of the part and could lead to failures in the field. The part change bypassed Moore's Engineering Change Process and therefore was not evaluated as their program requires. An Extent of Condition review performed by the OEM verified no additional part changes at Moore went unevaluated. The orders were delivered to the following facilities: Clinton, LaSalle, Byron, Callaway, Fermi 2. Notified R3DO (Daley), R4DO (Allen), and Part 21 Group via e-mail..
During the ATC root cause investigation, a technical error in the original qualification document S2000-RP-03, Revision 0, issued on February 7, 2000 was identified. The qualification test report identified the Moore 535 SLP controller's ability to withstand a total integrated dose (TID) of 1E5 Rad. This information is in error and is related to the original report creator's misunderstanding of the relationship between the presence of semiconductor materials and a citation from an EPRI report on the effects of radiation. The Moore 535 controllers have been tested for a TID of 1E3 Rad without failure. A report revision will be issued to clarify this item. No orders reviewed were provided for IEEE 323 harsh environment applications. Because the end-use application of each specific item is not known by ATC Nuclear, the safety hazard evaluation has been deferred to customers. The licensees above have been formally notified of the defect. Notified R3DO (Daley), R4DO (Allen) and Part 21 group via email. |
| Where | |
|---|---|
| Moore Controllers Oak Ridge, Tennessee (NRC Region 1) | |
| Organization: | Atc Nuclear |
| Reporting | |
| 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
| Time - Person (Reporting Time:+9.58 h0.399 days <br />0.057 weeks <br />0.0131 months <br />) | |
| Opened: | Greg Hott 13:35 Oct 6, 2011 |
| NRC Officer: | Bill Huffman |
| Last Updated: | Jul 7, 2012 |
| 47326 - NRC Website | |
Moore Controllers with 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
WEEKMONTHYEARENS 473262011-10-06T04:00:0006 October 2011 04:00:00
[Table view]10 CFR 21.21(d)(3)(i), Failure to Comply or Defect Part 21 Notification Concerning Moore Process Controllers 2011-10-06T04:00:00 | |