Often when we hear technical terms involving power quality such as total harmonic distortion, common coupling, and harmonic voltage factor our eyes glaze over and we throw up the white flag. Yes, there are some impressive algorithms involved in some of those terms, but in the maintenance and reliability world we can look beyond the details to the end game which is heat. Heat has been identified as the number one killer of electric motor insulation and the bottom line is poor power quality creates excessive heat. High distortion levels in the power being delivered to a motor will result in current flow through the motor that performs no real work. This harmonic current added to the real work current often results in the motor running in an overloaded condition electrically even though the horsepower delivered is at or less than rated horsepower.