A three-wire proximity sensor has three separate electrical connections that supply power and carry the output signal. These are typically brown, blue, and black wires, and each wire has a specific function that allows the sensor to operate accurately and safely in an automation system. The Omron three-wire proximity sensor follows this same international wiring standard for easy integration into control panels and PLC systems.
The brown wire is for the positive power supply (V+), providing operating voltage to the sensor. The blue wire is for the negative or ground (0V), completing the power circuit. The black wire serves as the output signal wire, which changes state when the sensor detects an object. Depending on the sensor type, this output can be either NPN (sinking) or PNP (sourcing). For example, in an Omron PNP sensor, the black wire outputs a positive signal when an object is detected, while in an NPN sensor, it connects the output to ground during detection. This simple three-wire design allows stable power supply and reliable signal transmission, making Omron proximity sensors ideal for use in automation, machine control, and industrial monitoring applications.