Drives and Controls Magazine
Module sends Ethernet comms on two-wire cables
Published:  14 March, 2014

Siemens has developed a device that allows two-wire cables, such as Profibus cables, to be used to carry Ethernet communications over distances of up to 1km without needing extra hardware, such as modems. The MM992-2VD media module can be used to convert existing cable infrastructures in machinery and plants quickly and economically to Ethernet networks.

The module’s bandwidth depends on the length and quality of the cable but, as a rule, bandwidths of 100 Mbit/s can be implemented over distances of up to 500m, while 1km-long cables will have bandwidths of 10 Mbit/s.

Siemens says that the module represents an simple method of migrating to Profinet, particularly in view of the widespread use of Profibus cabling.

The module can also be used to extend the maximum cable length in Ethernet networks for bandwidths of 100 Mbit/s. It allows remote network nodes to be integrated easily into Ethernet networks over distances of 100–300m using standard copper cables instead of the fibre optic cables previously needed for such connections.

Repurposing cables: Siemens' Ethernet media module

The media module can be used with any modular switch in Siemens’ Scalance X-300 range, and with its Scalance S627-2M security module. The cables are connected to the module via an RJ-45 connector.