What is the IO-Link Interface?

IO-Link Interface

IO-Link was the first I/O interface with an international standard. Currently, the process of sensor intelligence is well underway, with new standards for information sharing between devices emerging. These standards include the IO-Link interface. Leading firms have created IO-Link, sensor, and control systems.

As a result, automation has produced an automated field process interface (as opposed to PROFIBUS). IO-Link is a “point-to-point” interface with simple addressing.

Among other standards, the IO-Link interface allows for remote parameterization, diagnostics, and the sending of sensor and device status information.

The device is ideal for applications involving smart sensors. This standard’s typical network structure includes an

  • IO-Link Master (lead) and

  • Other IO-Link devices, most of which are intelligent sensors and drivers (inverters).

IO-Link simplifies the process of replacing malfunctioning network devices, that is, when a malfunctioning device is replaced with a new one, no additional adjustments are required because the (IO-Link master) leading device loads the parameters of the replaced device into the new device.

IO-Link Communications

IO-Link communications are carried out on a physical level using common three-core cables and connectors which include M12, M8, and M5.

Because the IO-Link interface is “point-to-point” in nature, just a single device can be attached to each port of the IO-Link master device.

The leading devices (IO-Link masters) can vary, comprising individual devices that enable open industrial networks via

  • PLC,

  • PROFIBUS, or

  • PROFINET interfaces.

Many manufacturers have recently adopted this standard in their automated processes.


  • IFM, and

  • Novotechnik

are some of the companies involved.

They manufacture

  • IO-Link Master devices (IO-Link Master),

  • Sensors (Level, Flow, Position), And

  • Input-Output Modules.