Photoelectric Sensor | 4M Detection Range | Industrial Use

This E3JK retroreflective photoelectric sensor finds objects over long distances. It sends a light beam to a reflector. It detects when something breaks that beam. With a sensing range of up to 4 meters, it's a useful photoelectric proximity switch. Features and Benefits - 4-meter sensing distance - Good for checking large areas, like warehouse doors or long conveyor lines. - Retroreflective sensing method - Finds objects reliably, even dark or see-through ones, using a special reflector. - AC/DC and DC-only models - The E3JK-R4M1 uses 90-250V AC/DC, and the E3JK-R4M2 uses 12-24V DC, so you can match your power. - Built-in relay output - Can switch small things directly, like indicator lights, buzzers, or counters, without another relay. Applications - Automatic gates and doors - Sees vehicles or people to stop the gate from closing on something. - Industrial conveyor systems - Counts items as they pass or confirms they are in the right spot. - Packaging machinery - Makes sure boxes are placed correctly before filling or sealing. How They Work A photoelectric sensor, also known as an optical or light sensor, operates by detecting changes in light. It comprises a light emitter and a receiver. The emitter sends out a beam of light, and the receiver detects this light. When an object interrupts or reflects this light beam, the sensor registers a change. This change in light reception triggers the sensor's output, indicating the presence or absence of an object. This Photoelectric Sensor uses a retroreflective method to achieve its 4m detection range. 3 Main Types of Photoelectric Sensors There are three primary types of photoelectric sensors. The first is through-beam, where the emitter and receiver are in separate housings, and detection occurs when an object breaks the beam. The second is diffuse-reflective, where the emitter and receiver are in the same housing, and detection happens when light reflects directly off the object. The third type, like this product, is retroreflective, where the emitter and receiver are in one housing, and a reflector is used to bounce the light back to the sensor. Common Applications Photoelectric sensors are versatile and widely used in industrial settings. Their ability to detect objects over a 4m distance makes them suitable for various tasks. Common applications include conveyor belt systems for counting or positioning items, automated doors or gates for safety and access control, and packaging machinery for product verification. As a proximity switch, this sensor can reliably determine the presence of objects without physical contact, making it ideal for many automated processes. The Core Components Every photoelectric sensor, including this industrial model, consists of a few essential components. At its heart are the light emitter and the light receiver. The emitter typically uses an LED to send out a light beam, while the receiver, often a phototransistor or photodiode, detects this light. These components are housed within a robust casing designed for industrial use. The sensor also includes processing circuitry to interpret the light signals and a low voltage power supply, suitable for below 50Vac or 75Vdc systems. The 3 Main Operating Modes Photoelectric sensors generally operate in three main modes. The first is through-beam, where the sensor detects an object when it blocks the light beam between a separate emitter and receiver. The second is diffuse-reflective, where the sensor detects an object by sensing the light reflected directly off its surface. The third mode is retroreflective, as featured in this Photoelectric Sensor. In this mode, the sensor detects an object when it interrupts the light beam travelling between the sensor head and a separate reflector.