A 2-wire proximity sensor works by using only two connection wires that supply both power to the sensor and carry the output signal to the load. Unlike a 3-wire sensor that has a separate signal line, the 2-wire type shares the same circuit for power and output, making it simpler to install. Inside the sensor, an oscillator generates an electromagnetic field (in inductive models) or a capacitance field (in capacitive models). When a target object enters this field, the signal changes, and the sensor switches its output state. This change is transmitted along the same two wires used for power, allowing the connected device or controller to detect the presence or absence of the object.
An Omron 2-wire proximity sensor is designed to offer stable and reliable operation in various industrial applications. It typically operates on a DC or AC power supply and features built-in protection against surge voltage and polarity reversal. These sensors are ideal for detecting metal parts, monitoring machine components, or replacing traditional limit switches. Because of their simple wiring design, they are easy to install in tight spaces and require less maintenance. However, they have a small leakage current even when turned off due to the shared power and signal path. Omron’s 2-wire proximity sensors are built to handle this efficiently, ensuring accurate detection, long service life, and compatibility with a wide range of automation equipment.