Omron NYP - 1 Series, Hardware User Manual

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Considerations for Earthing Methods
Local potential fluctuations due to lightning or noise occurred by power devices will cause potential
fluctuations between ground terminals of devices. This potential fluctuation may result in device mal-
function or damage. To prevent this, it is necessary to suppress the occurrence of a difference in elec-
trical potential 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.
Specification of commu-
nications cables
Earthing methods
Equipotential bonding
system
Star earthing Daisy chain
The cable shield connect-
ed to the connector hood
at both ends of the com-
munications cable Recommended Not recommended Not recommended
Additional Information
• In a country or region where the earthing method is 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.
• Ethernet switches are used with the EtherNet/IP. For information on the environmental resist-
ance of the Ethernet switch to use, the grounding between Ethernet switches, or the specifi-
cations of cables, ask the Ethernet switch manufacturer.
Each of these earthing methods is given below.
5 Installation
5-30
NY-series Industrial Panel PC Hardware User's Manual (W555)