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Entry type: Application example, Entry ID: 109739689, Entry date: 06/29/2017

Communication with S7 CPU via KNX Gateway

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This application example shows, how you configure communication via a gateway between SIMATIC S7 CPU and a KNX device via the KNX bus.

Gateways enable communication between two networks/bus systems that use different communications protocols.
KNX is a fieldbus for building automation. Technically, KNX is the successor to the European Installation Bus (EIB), adding communication mechanisms and transmission media.

The task is to establish, using a KNX gateway, a communication connection between an S7 CPU via PROFINET (PN) and a KNX device via the KNX bus.

The figure below provides an overview of the automation task.

Figure 1

Representing all SIMATIC controllers, this solution uses an S7-1200 CPU. The diagrammatic representation below shows the most important components for communication between an S7-1200 CPU and a KNX network using the “Triple-X PROFINET + KNX” universal gateway from MBS GmbH.

Figure 2


The solution presented here offers the following advantages:
  • Easy adaptation to other controller families. Representing all other SIMATIC controllers with a PROFINET IO interface, this solution uses the S7-1200 CPU.
  • Easy adaptation when expanding plants. The gateway is configured directly in the gateway’s integrated web server.
  • Integration of the gateway as a PROFINET IO device via a GSD file.
  • Gateway as distributed I/O with up to 340 bytes of input and 340 bytes of output.
  • Up to 2500 data points possible for communication between PROFINET and KNX.

  Documentation (2,5 MB)
 Registrierung notwendig  109739689_KNX_S7_PROJ_V10.zip (589,0 KB) 
 Registrierung notwendig  109739689_KNX_Gateway_RestoreFile_V10.zip (4,2 KB) 
 Registrierung notwendig  109739689_KNX_ETS5_PROJ_V10.zip (1,2 MB) 

Further information
Homepage of the company MBS GmbH

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