IO-Link communication principles

IO-Link - what is it?

Definition and explanation of the basics of IO-Link technology

IO-Link is a standardised point-to-point connection technology that has been enabling seamless communication between sensors, actuators, and controllers since its launch in 2009.

As an advanced communication protocol, IO-Link ensures the real-time exchange of process data, diagnostic data, and parameterisation information via a bidirectional interface.

Origin: From consortium to community

IO-Link technology was developed by a group of leading companies within the automation industry with the aim of creating a uniform, flexible, and standardised communication solution. Together, this group forms the IO-Link consortium, which includes ifm and Siemens. The consortium was founded to standardise and further develop IO-Link.

The IO-Link Community (https://io-link.com) supports this initiative by ensuring the uniform implementation of the standard worldwide. It offers resources on IO-Link communication principles as well as additional support, such as training on the implementation and use of the technology.

Parameterisation of IO-Link devices: Simple, even without prior programming knowledge, thanks to IODD

The configuration and parameterisation of IO-Link devices is simple and does not require any prior programming knowledge. For this reason, we don't tend to talk about programming in conjunction with IO-Link.

Only so-called IODD files (= IO device description files) are required, which contain all the relevant data structures, parameters, and device descriptions, as well as device IDs. Thanks to these standardised files, even users without prior technical knowledge or programming skills can parameterise and integrate IO-Link systems quickly and effortlessly.

Manufacturers or suppliers of IO-Link devices provide so-called digital libraries, in which the IODD data is available for download.

Alternatively, you can also obtain the IODD from the database of the IO-Link Community: https://ioddfinder.io-link.com/.

Software and tools for IO-Link configuration

The configuration and parameterisation of IO-Link devices is usually realised using specialised software tools. These are to be selected on the basis of the IO-Link master used.

The tools for IO-Link configuration read the IODD files and provide all the necessary options, such as user interfaces and configuration tools.

If you are using an IO-Link master from ifm, parameterisation is carried out using the manufacturer's own moneo configure SA software.

moneo configure SA is available free of charge and provides support with direct adaptation during operation (online parameterisation) and when configuring settings in advance (offline parameterisation). You can download the software here: www.ifm.com/de/de/product/QMP010.

However, if you are using a Siemens IO-Link master instead, the manufacturer's chargeable TIA Portal is required for configuration.

With moneo, you can benefit from smooth configuration without any prior programming knowledge. Other tools such as the TIA Portal require a little more knowledge.

PQI for predictive maintenance and maximum production efficiency

The IO-Link communication principles show that the technology isn't just used for exchanging process data, but also for recording detailed diagnostic data in addition to this process data exchange.

A central component in this regard is "Process Quality Information" (PQI for short), which provides a valuable basis for "Predictive Maintenance".

PQIs include status bits, which display the current switching status of the outputs. They also provide information concerning the operating status and functionality of the IO-Link-capable sensors/actuators in real time.

In summary, PQIs enable the precise monitoring and early identification of imminent malfunctions or anomalies.

Together with other diagnostic data, they support proactive maintenance management and help to reduce downtime while maximising production efficiency and process reliability.

The IO-Link communication interface is particularly flexible and demonstrates its advantages in numerous application areas:

• Food and beverages industry:

IO-Link enables the continuous monitoring of process parameters such as temperature, pressure, and fill level and thus contributes to compliance with strict legal hygiene regulations. Whether in milk processing, beer production, or other production processes, IO-Link helps to ensure flawless product quality and food safety.

• Automotive industry:

IO-Link technology can be used for the precise control and monitoring of assembly lines, resulting in a reduced error rate and increased production efficiency.

• Packaging industry:

IO-Link optimises flexibility and precision in packaging systems by enabling the precise control of system parameters and simple adaptation to suit different packaging formats. This reduces downtime and increases production speed.

• And much more:

Wherever flexibility, high production efficiency, precise production processes, and short downtimes play a role, IO-Link-capable solutions are a must.

Our IO-Link-capable solutions from the Automation24 range are as comprehensive as the areas of application for IO-Link. The above products should therefore give you an foretaste of what is available. In addition to IO-Link programming tools and accessories for IO-Link, our portfolio also includes many other products.

Fancy a quick introduction to the world of IO-Link? Then our IO-Link Master Starter Kits are just the thing!

If you would like to find out more about IO-Link or our product range, simply contact us - we will be happy to advise you!

Practical IO-Link example from the food industry

Part I: Thomas K. can plan system maintenance thanks to IO-Link

In the food industry, consistent and flawless product quality is of crucial importance. Unexpected machine failures not only jeopardise quality, but can also incur considerable cost.

Thomas K., maintenance manager at a company within the milk processing sector, is all too aware of this fact. He regularly monitors his sensors via the moneo dashboard from ifm.

Today he notices an anomaly: the status bit of the Picomag DMA15-AAAAA1 flow sensor, which can measure temperature as well as flow rate, is indicating an imminent failure.

The last measured temperature exceeded the maximum permissible limit of 70°C for which the sensor is designed.

As the sensor is only temperature-resistant up to a certain maximum temperature, there is a risk that the pressure sensor will be damaged if the temperature is exceeded. The error code read-out indicates that the temperature sensor is no longer functioning. A defective sensor jeopardises proper production. Thomas K. does not want to take any risks and plans to proactively check the sensor before the next production process and replace it if necessary.

Part II: Thanks to the IO-Link master, the flow sensor can be quickly replaced

Thomas K. appreciates the advantages of IO-Link technology, which has been in use in his company since last year.

The replacement of the flow sensor is quick and easy, as the identical new sensor is automatically configured with the saved parameters thanks to the activated recovery function.

The production process does not have to be interrupted and the quality of the products remains consistently high.

For Thomas K., IO-Link has now become indispensable.