Retrofit Ethernet for Siemens S7-300 and S7-400 PLC

An alternative to CP343 and CP443

A retrofit causes problems

Retrofitting an existing system with Ethernet can be expensive and complicated. Often old Siemens PLCs of type S7-300 or S7-400 are still in use, which do not have a Ethernet or RFC 1006 interface on board. They can be retrofitted with Siemens CPs (343 or CP443). However, a free slot in the S7 rack is required for this. Furthermore, the system configuration must be adapted.

The solution to these problems is simple: Our Profibus/MPI adapter.

Plug it on, configure it quickly and easily via web-interface: Done!

What’s a CP?

A communication processor or CP for short enables a Siemens S7 PLC, e.g. S7-300, to communicate via a data bus. A very widely used CP is the CP343-1, which can be used to add an ISO-on-TCP interface, i.e. Profinet, to an S7-300 module.

Profinet Profibus adapter

This fast and cost-effective adapter can be plugged directly into the PLC and is compatible with all Simatic S7 200, 300 and 400 CPUs. It combines flexibility and a compact design. The power is supplied either via the CPU of the automation device or optionally with DC 24 V from an external source. The network connection can be used with any standard Cat-5 cable (Ethernet).

As an ideal addition to our software products, this Profibus/MPI adapter is suitable for upgrading older machines and systems at low cost.


  • Can also be used in full racks

  • Simple web configuration

  • Compatible with all PLCDataTools

Get a price list and more information

Price list

Get a price list and further information

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