Installation guide

Network Infrastructure for EtherNet/IP™
Planning the Infrastructure
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wires) and four twisted-pair (eight wires) UTP cables. Two twisted-pair cables support network speeds of
10 Mbps as well as the 100-Mbps. Industrial Ethernet systems with 1-Gbps speeds use four twisted-pair
cables with a maximum cable length of 100 meters (328 ft). Pre-configured Category 5e (CAT 5e) cables
are available in required lengths. Field terminations may require manual work with crimping tools, bulk
cable, and connectors.
The quality of the cable and of the connector termination is particularly important at the high data rates
and in the electrically noisy environments of industrial Ethernet.
Only the highest quality, industrial grade Category 5e (or higher) cable should be used in industrial
Ethernet applications. Category 5e (e for enhanced) has superseded the older CAT 5 designation for 100-
Mbps systems. CAT 5e can contain either two twisted pairs (four wires) or four twisted pairs (eight
wires). The added wires and improved signal transmission characteristics allow CAT 5e cables to be used
for 1-Gigabit Ethernet and all power-over-Ethernet applications. However, two twisted-pair cables have
the advantages of compatibility with M12 (IP65 and IP67 grade) connectors and, in 100-Mbps
applications where only two pairs carry communications, this reduces the chance of electrical noise
interference.
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3.3.3.2 Shielded Category 5e Cable
Shielded cable should be considered for use in high noise environments. It also is the prevalent cable used
in European installations. See 4.4 Layout and Wiring Considerations for more information.
3.3.3.3 Connectors and Pre-terminated Cables
The RJ-45 connector is the standard for twisted-pair cabling. The IEEE Std 802.3
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and TIA Std TR42.9
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industry standards groups are in the process of specifying IP65 and IP67 versions of industrialized
Ethernet connectors.
“D”-coded M12 connectors with four wires are used to create IP65 and IP67 fluid-resistant, sealed
connections. These connectors allow removable connections to panels and connection of machine-mount
control devices. See 7.1.2 M12 “D”-Coded Connector for EtherNet/IP for more information.
The use of pre-terminated cables should get serious consideration, especially for 100-Mbps and 1-Gbps
connections. Improperly terminated cables can degrade the signal or provide a path for electrical noise to
enter, causing intermittent communications or reduced system throughput as the devices are forced to re-
transmit a higher percentage of messages.
3.3.3.4 Crossover vs. Straight-through Cables
Unlike device-level networks, different types of Ethernet devices require different pin-to-pin connections.
Some devices require the use of
crossover cables where the transmit pins at one end of the cable are
connected to the receive pins of the other connector. Other devices require a 1:1 (straight-through) cable
where the transmit pins at one end are connected to the transmit pins of the other.
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The Ingress Protection (IP) code IP65 refers to equipment that is dust-tight and protected against water jets. IP67 refers to
equipment that is dust-tight and protected against immersion in water. See Appendix E for more information.
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IEEE 802.3, http://standards.ieee.org/getieee802/portfolio.html
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TIA TR42.9, Industrial Telecommunications Infrastructure Standard. www.tiaonline.org