Harmonics are multiples of a fundamental frequency. for example, in a 60 Hz system, the 5th harmonic is 300 Hz. The total amount of harmonics in a power system is referred to as Total Harmonic Distortion (THD). Non-linear loads such as Adjustable Speed Drives, 6-pulse Converters, Uninterruptible Power Supplies, etc. are likely causes of damaging harmonics in your system.
When present in a power system, harmonics often result in higher voltages and currents. This condition is known as poor power quality. Harmonics contribute to problems such as blown fuses, overheating of equipment, misfiring of AC and DC drives, to name a few.
Myron Zucker, Inc. provides active harmonic filter systems and line reactors.