What is THD and what does it have to do with home generators?

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Your home is no doubt filled with computers, flat screen TVs, audio equipment and computer boards in systems such as your HVAC system.  Did you know that these sensitive electronics require clean power? 

If you have an old generator in your home, you probably know what unclean power is.  Basically, you might know that all power is not the same and that power coming from your utility provider is cleaner than that coming from a generator.  To measure the cleanliness of power, electricians use a measurement called Total Harmonic Distortion (THD).  The more distortion, the more sensitive electronic devices won’t recognize the power type and they won’t work – or worse, they may get damaged.

Fortunately, the major generator manufacturers have been working on a solution to the Total Harmonic Distortion problem and have modernized home generators to provide an acceptable THD level in their newer models.  The standards call for a THD of less than 5% with 3% being preferred.  When the power goes out, you don’t want a potential for issues with these devices.  After all, you want a generator so that you life runs smoothly when power goes out; you don’t need to worry about your laptop too.

When shopping for a backup power generator, choose one with a THD of 5% or less and rest easy that you will be able to multitask in front of your TV with your iPad while your neighbors are waiting in the dark.

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