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Understanding Power Quality Harmonics


  • Harmonic Fundamentals
    • Why All the Concern?
    • Key Issues
    • The Concept of Harmonics
    • Harmonic Characteristics of Various Loads
    • Cancellation
    • Real Time Demonstration


  • Voltage Distortion Problems
    • Causes of Voltage Distortion
    • Resonance
    • Actual Example of Resonance
    • Capacitor Application Guidelines
  • Other Harmonic Problems/Solutions
    • Neutral Overloads
    • Instrument and Meter Errors
    • Transformer Heating
    • Application of IEEE 519
    • Filters
  • Questions/Open Discussion


What is a Harmonic?

The word "Harmonics" still causes the hair to raise on the back of an electrical engineer's neck. 

Basically, harmonics are integer multiples of the base power line frequency.   This base frequency is 60 Hertz (cycles per second) in the United States and Canada. So, the 3rd harmonic would be 180Hz, the 5th harmonic would be 300Hz, and so on.

The Institute of Electrical and Electronics Engineers (IEEE), has developed standards and guidelines for the presence of current and voltage harmonics.  This is commonly referred to as IEEE 519.

The information in the following tables is covered clearly in our training programs: