EN Revision Imported Date : 2/11/2019
EN Revision Text: POTENTIAL PART 21 INVOLVING A200 SERIES STARTERS
The following is excerpted from a report submitted by QualTech NP, Nuclear Division, Curtiss-Wright Corporation:
"Pacific Gas and Electric (PG&E) reported to QTNP [QualTech NP] that they have had eight Cutler Hammer A200 series starter failures since September 15, 2008. The failures would remain in the operated/energized contact state with power removed for some period of time. All starters impacted with this failure were continuously energized. The concern was that if tripped, that the main contacts would not open to protect the motor.
"Testing was performed by Eaton Industrial Controls Division after receiving defective samples from PG&E. The test report from Eaton was received by QTNP for further review and evaluation. On October 6, 2015 QTNP determined that the Cutler Hammer A200 series starter failures may be reportable and an extent of condition review needed to be done.
"The root cause was a silicon based mold release that remained on the molded parts and would come between the moving (magnet) & fixed armatures. When heated for an extended period of time, this material would become sticky causing anywhere from a minor delay in opening, up to a frozen closed condition.
"Cutler Hammer has determined that the silicone mold release was first introduced into the manufacturing facility in May, 2008, due to a shortage of the Zinc Stearate Mold release that was traditionally used. The silicon based mold release was periodically used until October 2012. According to Cutler Hammer, anything made after January 1, 2013 should definitely be silicon mold release free.
"Thus any starters/contactors of the CH A200 series manufactured between May 2008 & December 31 , 2012 could have this concern. This failure has only been reported for continuously energized applications. The end user should evaluate their applications for this potential failure mechanism."
QTNP has notified North Anna, H. B. Robinson, Diablo Canyon, and Hatch.