Your dog didn't eat your homework, and lightning didn't kill that motor

Abstract

Countless times each year, lightning is wrongly blamed for electric motor failures. This paper addresses ways to differentiate between damage from lightning and that caused by inadequate ground fault protection or multiple start attempts after the initial failure. Transient conditions, rapid bus transfer, and ungrounded systems often mislead the repairer into blaming lightning for motor failures. A list of similar transients would have to include re-closure, improperly located power factor correction (PFC) capacitors, accidental connection of a new dual-voltage motor for the wrong voltage, and lightning.