How do you assign the IO-Link interface protocol in Siemens TIA?

From the sensor interface to the controller – how to assign data correctly

A frequent question from the field: “How do I know what data my sensor is sending to the Siemens TIA controller via IO-Link or PROFINET – and where this data arrives in the controller?”

Sensors can be seen, from which black cables lead to an IO-Link master in the middle. From there, a green cable goes to the controller.
The IO-Link system architecture enables bidirectional communication between sensors, actuators and the controller, which serves as the computing unit of the overall system.

When integrating wenglor sensors with IO-Link or PROFINET into a Siemens TIA controller, it is important to know which data the sensor sends and where it arrives in the controller. The interface protocol serves as the basis here: It shows the exact assignment of the transmitted data – from the interface protocol of the sensor to the TIA addresses in the controller.

Why the interface protocol is so important

The interface protocol transparently shows which bytes and bits the sensor transmits and the meaning of this information – for example measured values, status information or diagnostic data.

Only if this structure is known can the received values be correctly interpreted in the control system, read out and used for further automation tasks.

Example: PROFINET interface protocol of a laser distance sensor

The example of a P3PC Laser Distance Sensors Triangulation shows how this assignment works. The data structure can be divided into three levels:

  • Sensor protocol (bottom left): Shows the bit and byte assignment that the sensor transmits. Here you can see which information is contained in which data area.
  • TIA controller (bottom right): In the Siemens TIA environment, this data is mapped to specific addresses and variables – for example as Boolean, integer or real values.
  • General overview (top): Illustrates the complete data flow – from the sensor to the communication protocol to the application level in the controller.
The picture shows three tables: the sensor protocol, the TIA control interface and an overview of the data flow.
Example of the PROFINET interface protocol of a laser distance sensor.

The result: clear data structures and simple integration

With the interface protocol, communication between the sensor and the controller can be tracked transparently. This allows measured values to be reliably assigned, diagnoses to be made more quickly and processes to be automated more efficiently.

Whether for the initial start-up of new systems or the optimization of existing systems – an understanding of the assignment of process data is the key to reliable and high-performance sensor integration.

Author

Picture of Max Mustermann

Max Mustermann

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