Yaskawa Inverter Products Conform with the EMC Directive - Manual (Page 5)

Page 5 of 34
3. Countermeasures for AC power supply and surrounding
3.1. Line Filter
With regard to noise that is conducted on mains power supply by Inverters, a line filter is used as a
countermeasure.
In order to keep the EMC limits the recommended filters for YASKAWA Inverters. (Refer to APPENDIX 1)
must be used.
3.2. Installation and wiring
The line filter and the Inverter must be mounted on a same metal plate. The filter should be mounted as close
as practical to the inverter. Keep cable as short as possible. The metal plate should be securely earthed. The
frame (earth) of line filter and Inverter must be bonded to the metal plate with as much area as possible.
For the motor cable, screened cable must be used and the screen of the motor cable is connected to earth at
both ends by a short connection using as large area as practicable.
4. Treatment of cables
4.1. Countermeasures against cable noise
The treatment of cables is the most important countermeasure. The machinery manufacturers are requested
to examine the current structure of the cable lead - in.
- Use cables with woven screen
-
The screen of the cable should be earthed with a large area.
- It is desirable to earth the screen of the cable by clamping the cable to the earth plate.
- The screen must be earthed on both side of the cable ( take care for good earthing system )
Ground bonds, remove any paint
Examples :
Number 1,2,3 show not proper ways to earth
a cable screen.