IO-Link

IO-Link is a standardized point-to-point communication technology for sensors and actuators, specified in IEC 61131-9. It uses a three-wire sensor and actuator connection and can be integrated into fieldbuses. It supports bidirectional communication for diagnostics and parameterization at three communication speeds: 4.8 kBaud, 38.4 kBaud, and 230.4 kBaud.

Source checked3/3 values · 2026-10-25

Specification

2 sources

Transports	serial
Architecture	master slave
Encoding	binary
Standard body	IEC
Standard ref	IEC 61131-9

Study notes

IO-Link is not a fieldbus; it is a point-to-point connection technology for sensors and actuators.
IO-Link uses standard M12, M8 or M5 connectors and three-wire cables.
IO-Link supports three communication speeds: 4.8 kBaud, 38.4 kBaud and 230.4 kBaud.
IODD (IO Device Description) is delivered as a compressed ZIP file containing the main IODD file, optional language and image files, and the manufacturer's declaration.
IO-Link device profiles standardize process data, parameters and functions for sensors.
IO-Link Wireless removes physical cables while maintaining real-time communication between sensors, actuators and control systems.

Safety

IO-Link Safety supports functional safety applications.
IO-Link Safety Masters implement communication in higher-level systems such as PROFIsafe, CIPsafety or FSOE (Safety over EtherCAT).
IO-Link Safety Devices can be used unchanged in higher-level systems.