Wiring With Ethernet Cable - Omron CJ2 User Manual

5 Installation
5-3-6

Wiring with Ethernet Cable

Precautions
Observe the following precautions when using the CJ2 CPU Unit built-in EtherNet/IP port.
Basic Installation Precautions
• Take the greatest care when installing the Ethernet System, being sure to follow ISO 8802-3 spec-
ifications. You must obtain a copy of these specifications and be sure you understand them before
attempting to install an Ethernet System.
• Unless you are already experienced in installing communications systems, we strongly recom-
mend that you employ a professional to install your system.
• Do not install Ethernet equipment near sources of noise. If a noisy environment is unavoidable,
take adequate measures against noise interference, such as installing network components in
grounded metal cases or using optical cable in the system.
• When installing an EtherNet/IP network that combines an information system with the control sys-
tem, and the communications load may be heavy due to tag data links, we recommend configur-
ing the network so that the load does not affect communications. For example, install the tag data
links in a segment that is separate from the information network.
Precautions on Laying Twisted-pair Cable
• Noise resistance may be reduced by ground loops, which can occur due to improper shield con-
nections and grounding. Ground the shield at one location, as shown in the following diagram.
• Do not connect the connector shield at the CPU Unit.
• If a cable connects two hubs, connect the shields at only one end.
Hub
Connector
GR
• Press the cable connector in firmly until it locks into place at both the switching hub and the CPU
Unit.
• Do not lay the twisted-pair cable together with high-voltage lines.
• Do not lay the twisted-pair cable near devices that generate noise.
• Do not lay the twisted-pair cable in locations subject to high temperatures or high humidity.
• Do not lay the twisted-pair cable in locations subject to excessive dirt and dust or to oil mist or
other contaminants.
5-36
Hub
Connector Connector Connector Connector
GR
STP
(Shield)
Connect shield.
Do not connect shield.
EIP Power
Unit Supply
Unit
Connector
GR
STP
terminal
(Shield)
EIP Power
Unit Supply
Unit
Connector
GR
STP
terminal
(Shield)
CJ2 CPU Unit Hardware User's Manual