Omron CJ1W-SCU32 Operation Manual page 35

EMI Measures for Serial Communications Boards and Units
The CS/CJ-series PLCs conform to the Common Emission Standards (EN 61000-6-4 or EN 61131-2)
of the EMC Directives. However, the noise generated from Serial Communications Board or Unit com-
munications cables may not satisfy these standards. In such a case, commercially available ferrite
cores must be placed on the communications cable or other appropriate countermeasures must be pro-
vided external to the PLC.
Recommended Ferrite Cores
The following ferrite core (data line noise filter) is recommended:
0443-164151 by Fair-Rite Products Corp.
Low impedance, 25 MHz: 90 Ω, 100 MHz: 160 Ω
Recommended Mounting Method
Mount the core on one turn of the communications cable, as shown in the following illustration.
Mount the cores as lost to the end of the communications cable as possible, as shown in the following
illustration.
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
Serial
Commu-
nications
Unit/Board
Regulations and Standards
33