The **E3G-R17** is a high-performance, long-distance retro-reflective photoelectric sensor manufactured by Omron. It is designed for industrial automation environments where robust detection is required over significant distances. --- ## 1. Core Technical Specifications The following table outlines the primary electronic and operational characteristics of the E3G-R17: | Feature | Specification | | :--- | :--- | | **Sensing Method** | Retro-reflective (requires a reflector) | | **Sensing Distance** | 10 meters (when using E39-R2 reflector) | | **Supply Voltage** | 12 to 240 VDC / 24 to 240 VAC (Multi-voltage) | | **Output Type** | Relay Output (SPDT - Single Pole Double Throw) | | **Control Output** | 3A at 250 VAC (Resistive load) | | **Response Time** | 30 ms Max. | | **Light Source** | Infrared LED (Non-visible) | | **Connection** | Terminal Block / Conduit entry | --- ## 2. Key Electronic Components & Internal Design ### A. The Emitter and Receiver The E3G-R17 utilizes an **Infrared (IR) LED** emitter and a **Photodiode** receiver housed within the same unit. Because it is a retro-reflective sensor, the IR beam travels to a reflector and back. The electronics analyze the interruption of this light circuit. ### B. Multi-Voltage Power Supply One of the standout electronic features is its **Universal Voltage** capability. * It contains an internal switching power supply or voltage regulator circuit that allows it to accept both high-voltage AC and low-voltage DC without manual adjustment. * This makes it versatile for different industrial power grids. ### C. Relay Output Circuitry Unlike NPN/PNP transistor-based sensors, the E3G-R17 uses a physical **Relay**. * **Advantages:** It can switch high-current AC loads directly. * **Durability:** The relay provides electrical isolation between the sensor's internal logic and the load being switched. --- ## 3. Configuration & Adjustments The sensor includes several user-serviceable electronic adjustments located under the protective cover: 1. **Sensitivity Adjuster:** A multi-turn potentiometer to fine-tune the sensing threshold (useful for detecting translucent objects). 2. **Operation Mode Switch:** Allows the user to toggle between: * **Light-ON:** Output energizes when the beam is unobstructed. * **Dark-ON:** Output energizes when an object breaks the beam. 3. **Timer Functions:** Some variants of the E3G series include an ON-delay, OFF-delay, or One-shot timer module built into the circuit. --- ## 4. Wiring Diagram Representation The terminal block typically follows this standard industrial layout: ```text Terminal 1 & 2: Power Supply (12-240V AC/DC, non-polar) Terminal 3: Common (COM) - Relay Contact Terminal 4: Normally Closed (NC) - Relay Contact Terminal 5: Normally Open (NO) - Relay Contact ``` ---