User Manual
EM100 Mini Inverter
108
Figure 8-1 Wiring and Shielded Grounding
8.3.3 Grounding
1. Inverter and other devices shall be grounded. If a common grounding point is required,
single point grounding is suggested, and common grounding cable is not recommended.
2. A grounding cable with large cross-section shall be taken for ensuring low grounding
impedance. For the cables with the same cross-sectional area, high frequency impedance
of flat conductor is smaller than that of a round conductor. Therefore it is better to take
flat cable. The grounding cable should be as short as possible, and the distance should be
as close as possible between the grounding point and the inverter.
3. If motor power cable is the quad cable, the grounding wire of quad cable must be
grounded in the inverter side, and the other side is connected to the grounding terminal
of the motor. The best grounding effect could be obtained if the motor and inverter have
their separated grounding points.
4. If the grounding terminals of all parts are connected together in the control system, the
noise source formed by the ground leakage current would affect the other peripherals in
the control system except inverter. Therefore, in the same control system, the groundings
shall be separated for the inverter and electrical devices such as computers, sensors or
audio.
5. In order to obtain lower HF impedance, take the fixing bolts as the HF terminal
connected to the cabinet back panel. Remove the insulating paint on the fixing point at
installation.
6. Laying grounding cables should be kept away from the wiring of noise-sensitive device
I/O part, while, the grounding cable should be as short as possible.
Figure 8-2 Correct Grounding Mode for Inverter and Other Devices
Figure 8-3 Incorrect Grounding Mode for Inverter and Other Devices
8.3.4 Handling the EMI of the peripherals on the inverter
The electromagnetic interference is generated because of relays, contactors and
electromagnetic brakes installed nearby the inverter. When the inverter has malfunction due
to EMI, following methods are recommended:
1.
Install surge absorber on the devices generating interference.
2.
Install EMC filter on the input power cable of inverter, refer to 8.3.7 for specific
operations procedures.
