The Difference Between Active or Passive Harmonics Energy Filters

Harmonics filters go a long way in making your electrical usage more efficient and effective.

Harmonics is electricity that is not in its proper 60 Hz phase. A perfect 60 Hz sine wave would have 0% Total Harmonics Distortion. Anything other than the fundamental line frequency is a harmonics distortion. Harmonics filters work to limit voltage fluctuation and reduce that “out-of-phase” energy that is grounded or goes back into the grid.

Without filtering harmonics can cause disturbances in the electrical grid that can damage equipment, increase your electrical bill and cause heating and efficiency losses.

You know you need one, but what is the difference between passive and active filters?

Passive Harmonics Filters

Passive harmonics filters are the more common devices used in a variety of capacities and voltages. These filters utilize components like inductors, capacitors and resistors. Passive filters generally filter noise on a single variable speed drive. They eliminate harmonics before the electrical current reaches equipment.

A great example of a passive filter is the OES-11 filter from Onics Energy. These filters are suitable to just about any kind of business and can reduce electricity costs by up to 25 percent.

Active Harmonics Filters

Active harmonics filters can work with many variable speed drives and actively reduce noise by constantly monitoring electricity and injecting currents to mitigate harmonics. Active filters are ideal for a system with many non-linear loads.

While these filters can handle a great deal they generally cost a lot more than a passive filter. Active filters also do not require a pre-study of the current’s harmonics prior to installation.

The biggest deciding factor in which kind of filter you need is the amount and kind of electricity you are using. For most businesses a passive filter is a perfect fit and can make a huge difference in energy efficiency.