Photoelectric Sensor with single -turn knob and LO and DO, PNP output function. Visible red light source and diffuse sensing mode. IO-Link is a worldwide open-standard peer-to-peer serial communication protocol (IEC 61131-9) that allows sensors and actuators to easily integrate into the connected enterprise. The IO-Link enabled 42EF sensor, when connected to an IO-Link master, shares device identity, parameters, real-time diagnostics and process data with the control system to optimize machine setup, maintenance and troubleshooting. By combining simple implementation with powerful data and diagnostics, IO-Link sensors provide simplified integration and seamless visibility of your processes to increase uptime and productivity.