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Siemens AG
Entry type: Application example Entry ID: 109778776, Entry date: 07/31/2020

LOGO! - S7 Connection with LOGO! Client and S7-1200/1500 Server

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This application example offers a completely configured S7 connection for LOGO! 8 ("LOGO!" for short) for communication with a SIMATIC S7 controller. You will use a LOGO! switching program connected to an S7 project, where you can test the connection and can freely expand it.

The inputs and outputs of a LOGO! base unit should be switched over a long distance using the inputs and outputs of a SIMATIC S7 controller.

The respective inputs and outputs are not connected by individual cables or wires, but via an Ethernet cable, shown in the figure below..

The connection runs physically via Ethernet and is configured as an S7 connection.
In this example LOGO! is configured as client and the S7 is used as the server.

The integrated functions of LOGO! offer many additional possibilities to solve applications in various areas quickly and easily.

With LOGO!, prefabricated function blocks support project creation, e.g. weekly time switch, pulse generator, astro timer, seasonal time switch, stopwatch and simple logic gates.

The LOGO! text display (TDE) and the integrated web server of LOGO! offer additional options for operation and monitoring using function keys and message texts.


  • Extendibility of the software program to include further tasks.
    In addition to the basic task description, additional independent subtasks can be configured depending on the application.
    For this purpose, LOGO! can be expanded with a wide variety of expansion modules.
  • Straightforward, star-shaped arrangement of the wiring of the components.
  • Use of simple switches (circuit breakers) or pushbuttons.
  • Fewer components are required compared to a conventional solution.
  • Communication options via Modbus/TCP, S7 connection, and KNX.

Target group
This application example is intended for specialists in electrical installations or automation.

Documentation and example project
  Documentation (1,9 MB)
 Registrierung notwendig  LOGO! programm and S7-project inside ZIP Archive (302,4 KB)

Additional keywords
S7-communikation, LOGO!-network, communication protocol

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