Omron MX2 Series - Page 106

2 Design
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Multi-function Compact Inverter 3G3MX2-EV2 User’s Manual (I666-E1)
In recent years, there is an increasing concern about harmonic currents generated from industrial
machinery.
The following provides an overview of harmonics and measures against harmonics implemented in this
inverter.
⚫ Harmonics
The voltage or current whose frequency is an
integral multiple of certain standard frequency
(base frequency) is called a harmonic.
If a commercial power supply frequency of 60 Hz
(50 Hz) is the reference frequency, the harmonics
of that signal is:
x2 = 120 Hz (100 Hz),
x3 = 180 Hz (150 Hz),
and so on.
⚫ Reason why harmonics cause problems
As the number of harmonics increases, the wave-
form of the commercial supply has more distor-
tion. This distortion causes the malfunction of the
connected equipment or leads to abnormal heat
generation.
Harmonic Current Measures and DC/AC Reactor Wiring (+1, P/+)
2nd harmonics (120 Hz)
Base frequency
(60 Hz)
3rd harmonics (180 Hz)
3rd harmonics (180 Hz)
Distorted waveform