Omron RX2 Series User Manual page 103

Wiring for Ground Terminal (G
To prevent electric shock, be sure to ground the inverter and the motor.
The 200-V class should be connected to the ground terminal under type-D grounding conditions (con-
ventional Class 3 grounding conditions: 100 Ω or less ground resistance). The 400-V class should be
connected to the ground terminal under type-C grounding conditions (conventional special Class 3
grounding conditions: 10 Ω or less ground resistance).
For the ground cable, use the applicable cable or a cable with a larger diameter. Make the cable length
as short as possible.
When several inverters are connected, the ground cable must not be connected across several invert-
ers or looped. Otherwise, the inverters and peripheral control equipment may malfunction.
Inverter
Inverter
Inverter
Harmonic Current Measures and DC/AC Reactor Wiring (PD, P)
In recent years, there is an increasing concern about suppressing the harmonic currents to the power
supply line in accordance with "Guideline to reduce harmonic emissions caused by electrical and elec-
tronic equipment for household and general use."
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 Prob-
lems
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.
High-function General-purpose Inverter RX2 Series User's Manual
)
Inverter
Inverter
Inverter
Base frequency
(60 Hz)
Base frequency (60 Hz)
Distorted waveform
2 Design
Your ground
bolt
2nd harmonics (120 Hz)
3rd harmonics (180 Hz)
3rd harmonics (180 Hz)
2
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