IO-Link Communication Standard

IO-Link Communication Standard

Seamless communication right through to the final steps of the process

Consistent cost reduction, high plant availability, and transparency – the requirements of point-to-point industrial communications are constantly increasing. At the same time, the actuators and sensors employed are becoming increasingly intelligent. This is where the open IO-Link communication standard comes in, enabling you to complete the final steps in the process – with data transparency from the sensor/actuator level all the way to the automation level. Not only do you benefit from a simple, consistent and inexpensive point-to-point connection, through which sensors and actuators can be linked to the control level, but also from systematic diagnostic concepts and efficient handling of parameter data on all levels of the automation system. IO-Link is the ideal basis for creating efficient transparency – not only in the control cabinet but also at field level.


IO-Link Master

To link IO-Link devices with your automation system, Siemens offers you a choice of IO-Link master devices for non-central peripherals, the SIMATIC ET 200 and the SIMATIC S7-1200 controller. These IO-Link master modules integrate fast and simple IO-Link communication with sensors and actuators in the established PROFIBUS and PROFINET field bus systems, and thereby in Totally Integrated Automation.

IO-Link masters from Siemens can be used to link IO-Link-certified sensors and actuators in all areas of production automation. Project planning of IO-Link channels can be performed easily, quickly and conveniently using the S7-PCT port configurator tool, which is integrated in STEP7 Engineering and is also available as a separate tool.

IO-Link Master Module for SIMATIC S7-1200

IO-Link Master Module for SIMATIC ET 200MP

IO-Link Master Module for SIMATIC ET 200SP

IO-Link Master Module for SIMATIC ET 200AL

IO-Link Master Module for SIMATIC ET 200eco PN

IO-Link Master Module for SIMATIC ET 200pro

Industrial Switchgear

Siemens industrial switchgear includes everything you need to integrate actuators into your automation system via IO-Link – easily, efficiently and reliably.

Whether compact starters, function modules for attaching to contactors, power contactors for motor switching, monitoring and temperature-monitoring relays, electronic overload relays or an electronics module – SIRIUS supplies you with all products with an IO-Link interface.

Temperature monitoring relay SIRIUS 3RS2

Monitoring relay SIRIUS 3RR24 and SIRIUS 3UG48

Electonic monitoring relay SIRIUS 3RB24

Compact starters SIRIUS 3RA6

Function modules SIRIUS 3RA27 for attaching to contactors

Commanding and Signalling Devices

Even SIRIUS ACT commanding and signalling devices can be connected to IO-Link. This includes the electronic SIRIUS ACT ID key switch, incorporating the latest RFID technology. This ensures that only authorised persons are able to operate the plants and machinery. It is also possible to quickly and safely connect SIRIUS ACT push buttons and light signalling devices to IO-Link, using special electronics modules for IO-Link.

SIRIUS ACT ID key switch

SIRIUS ACT electronics modules

8WD4 signalling columns


The SIMATIC RF 200 IO-Link RFID system was conceived for identification operations, such as reading ID numbers. The system comprises space-saving HR readers, which are especially useful in intralogistics and small assembly lines, where they enable very simple identification tasks, e.g. reading an ID number or any user data (‘read only’). It is especially cheap and simple to integrate the data read by the reader in the automation level with the aid of a standard interface for IO-Link.


IO-Link IO modules

The compatibility of IO-Link modules also allows an easy connection of standard sensors and actuators. Signals and energy is transmitted through IO-Link (IO-Link master). The IO-Link modules can be connected to any IO-Link master and thus enable a set-up of distributed I/O modules units that are fieldbus-independent. Due to the point-to-point connections in IO-Link, a star-shaped structure (star topology) is created when the IO-Link peripheral modules are connected to an IO-Link master. When connected to other SIMATIC ET 200 I/O modules, this star topology can be combined with the fieldbus line topology as required. In this way, a topology optimally adapted to the requirements of the machines and plants can be realized.



IO-Link software tools and functional modules ensure the standardised and efficient engineering and visualisation of diagnostic information. For instance, the PC-based S7 port configuration tool simplifies the parametrisation of Siemens IO-Link master modules and IO-Link devices from any manufacturer. In addition, Siemens supplies IODD device description files as well as functional modules and UDTs for all IO-Link devices in the Siemens portfolio that harmonise and simplify communication between IO-Link devices.

S7-Port Configuration Tool

IO-Link Function blocks

Device description files (IODD)


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