ENS 48798
ENS Event | |
|---|---|
05:00 Mar 1, 2013 | |
| Title | Part 21 - Dual Alarm Modules That May Contain Faulty Diodes in Single State Relays |
| Event Description | The following is excerpted from a facsimile received from Curtis Wright:
Crydom Inc., the sole supplier to Scientech of D4D07 Solid State Relays (SSRs) since before 2009, has informed Scientech that SSRs provided with date codes between 0908 (August 2009) and 1004 (April 2010) may have included faulty diodes which resulted in reduced reliability (early failure) of their SSRs. The mode of failure is that the module output may not be able to maintain voltage sufficient to activate its external load. It appears that this failure occurs randomly after some duration of operation, typically weeks or months. No common cause has been found. Scientech screens components for infantile failure by burning-in modules for a minimum of 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> prior to final test. There were no SSR failures during burn-in of potentially affected modules; therefore burn-in was not an effective screen for this issue. Prior to January 2013, Scientech did not track SSRs by date code. In establishing conservative boundaries for product shipped with suspect SSRs, Scientech can be certain that no suspect SSRs were shipped in Scientech products prior to August 2009 (the earliest suspect date code). It was determined in September 2012 that Scientech did not have any SSRs with a date code of 2010 or earlier in inventory or work-in-progress. Scientech can therefore determine that products shipped after September 2012 do not contain suspect SSRs. Affected components: DAM801, a Dual Alarm Module, manufactured by Scientech, Model DAM801 (/1 optional), Part number EIP-E287PA-1 SAM801, a Single Alarm Module, manufactured by Scientech, Model SAM801 (11 optional), Part number EIP-E289PA-1 DAM502, a Dual Alarm Module, manufactured by Scientech, Model DAM502, Part number EIP-E297DD-1, -2, -3 SAM502, a Single Alarm Module, manufactured by Scientech, Model SAM502, Part number EIP-E297DD-4 DAM503, a Dual Alarm Module, manufactured by Scientech, Model DAM503, Part number EIP-E304DD-1, -2, -3 SAM503, a Single Alarm Module, manufactured by Scientech, Model SAM503, Part number EIP-E304DD-4, -20 DAM504, a Dual Alarm Module, manufactured by Scientech, Model DAM504, Part number NUS-A131PA Affected Facilities: Beaver Valley Farley Ginna Indian Point 2/3 Kewaunee North Anna Prairie Island Surry Turkey Point
The following information was received via fax. Only information that has changed is being attached below. Thirteen plants were notified during the original notification. On March 10, 2015, one affected plant reported that when one SSR failed, its output consisted of high frequency noise at a reduced duty cycle. This noise caused overheating and failure of resistors in an RC filter connected to the alarm module output. Plants experiencing SSR failures should check downstream elements for possible consequential damage. Scientec has not received any other reports of this condition. The condition was reevaluated and the Part 21 evaluation was revised. The evaluation concluded that this newly identified condition does not impact the original defect as reported. Notified the R1DO (Dental), R2DO (Desai), R3DO (Roach), and Part-21 Group (via e-mail). |
| Where | |
|---|---|
| Crydom, Inc Danbury, Connecticut (NRC Region 1) | |
| Organization: | Curtiss Wright Flow Control Co. |
| Reporting | |
| 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
| Time - Person (Reporting Time:+6.67 h0.278 days <br />0.0397 weeks <br />0.00914 months <br />) | |
| Opened: | Michael Weinstein 11:40 Mar 1, 2013 |
| NRC Officer: | Charles Teal |
| Last Updated: | Mar 20, 2015 |
| 48798 - NRC Website | |
Crydom, Inc with 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
WEEKMONTHYEARENS 487982013-03-01T05:00:0001 March 2013 05:00:00
[Table view]10 CFR 21.21(d)(3)(i), Failure to Comply or Defect Part 21 - Dual Alarm Modules That May Contain Faulty Diodes in Single State Relays 2013-03-01T05:00:00 | |