Origins of high voltage continuity failures in enamel coated copper magnet wire

Abstract

Continuity testing of film insulated copper magnet wire is conducted under high-voltage AC conditions to determine the exact causes of electrical failures. A special apparatus is built to pinpoint the precise location of such defects. Using visual examination, metallographic evaluation of cross-sections, scanning electron microscopy (SEM) examination of the bare wire surfaces, and elemental analysis of foreign contaminants, the genus of continuity faults is categorized, and is broken down into six different major classifications. A comparison between beady wire and continuity failures is presented.