Industrial Communication Guide

ETHERNET IN INDUSTRIAL USE

These ensure permanent spacing between the wires. In contrast to the considerable variance in the case of fieldbuses, the characteris- tic impedance of a copper-based Ethernet cable is always 100 Ohm and typically +/- 15% tolerance.

All connectors mentioned above have the protection code IP20. In order to be able to use Ethernet in this context, the M12 connector familiar from the fieldbus module has been adapted. Typically, D and X coding are used for four and eight wires.

ETHERLINE ® Cat.7 FLEX

The connector In terms of connectors, the RJ45 connector has become established as the standard. Due to its design, however, this is not suitable for Categories 7, 7A and 8.2 (the contacts are positioned very close to each other, which can cause mutual interference). The limit values for Category 8.1 were deliberately defined so that the RJ45 is able to meet them. Other connectors – so-called chamber plugs – cluster the individual wire pairs so as minimize interference, enabling them to meet the more rigorous limit values of Categories 7, 7A and even 8.2. Typical representatives of these are TERA and GG45 connectors, though the latter have not yet achieved a very high level of market penetra- tion due to their high cost and the lack of compatible end devices.

RJ45

TERA

M12D

M12X

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