Omron CK3E Series, Hardware User Manual, Page: 73 / 114

4-8 Grounding
This section describes the earthing methods and precautions.
4-8-1
Considerations for Earthing Methods
Local potential fluctuations due to lightning or noise from power devices will cause potential fluctua-
tions between ground terminals of devices. This potential fluctuation may result in device malfunction
or damage. To prevent this, it is necessary to suppress the occurrence of a difference in electrical po-
tential between ground terminals of devices. You need to consider the earthing methods to achieve
this objective
The recommended earthing methods for each usage condition are given in the following table.
Specifications of communications
cables for EtherCAT and Ethernet
Earthing methods
Equipotential
bonding sys-
tem
Star earthing
Daisy Chain
Connecting
devices and
noise sources
to separate
earth electro-
des
Connecting
devices and
noise sources
to a common
earth elec-
trode
The cable shield connected to the con-
nector hood at both ends of the com-
munications cable Recommended Recommended Not recom-
mended Not recom-
mended
Additional Information
• In countries or regions where earthing methods are regulated, you must comply with the reg-
ulations. Refer to the applicable local and national ordinances of the place where you install
the system, or other international laws and regulations.
• When using Ethernet switches, ask the Ethernet switch manufacturer for information about
the environmental resistance of the Ethernet switches to be used, the grounding between
Ethernet switches, and the specifications of cables.
4-8-2
Grounding
This section describes the earthing methods and precautions.
Equipotential Bonding System
Equipotential bonding is an earthing method in which steel frames and building structures, metal ducts
and pipes, and metal structures in floors are connected together and make connections to the earth
trunk line to achieve a uniform potential everywhere across the entire building. We recommend this
earthing method.
The following figure shows an example of an equipotential bonding system.
Connect the main earthing terminal and building structures together with equipotential bonding con-
ductors and embed the mesh ground line in each floor.
4 Mounting and Wiring
4-23
CK3E-series Programmable Multi-Axis Controller User’s Manual Hardware (I610)
4-8
Grounding
4
4-8-1
Considerations for Earthing Methods