Benny G. Darsey
Tampa Armmature Works, Inc.

There are several reasons that random wound electric motors have premature electrical failures. There have always been concerns of crossovers in the slot section and end turns. Crossovers create unfavorable conditions such as keeping the varnish or resin from bridging the magnet wires and bonding them together. Crossovers also create pressure points. Pressure points, combined with the condition of poor bridging of the varnish and the line frequency vibration, will cause the magnet wire insulation to abrade, causing a short circuit.

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