The following report was received from the manufacturer via fax:
Nutherm International, Inc. reported on a defect found in "Moore Industries SCT Signal Converter (Part Number SCT/4-20MA/10-50MA/117VAC/UB) based upon the failure analysis of a failed component. The conclusion was that the wire insulation in T2 transformer was damaged by the transformer manufacturing facility during assembly. This damage reduced the insulation resistance and dielectric breakdown between the windings of the transformer. These damaged transformers were subsequently installed by Moore Industries into the signal converters. The failure of the transformer resulted in early, catastrophic failure of the signal converter.
Moore Industries tested the transformers remaining in stock and found one (1) of the remaining two-hundred nineteen (219) transformers exhibited this condition. In all documented cases involving failure of this transformer, the impacted units had passed pre-installation functional testing but failed within four months after installation.
Affected nuclear power stations include: Peach Bottom Atomic Power Station and the Sequoyah Nuclear Station.