The **E3F2-R4C4** is a cylindrical photoelectric sensor manufactured by Omron. It is a "Retro-reflective" type sensor, meaning it emits a light beam and requires a corner cube reflector to operate. --- ### 1. Technical Specifications The following table summarizes the core electronic and physical characteristics of the E3F2-R4C4: | Feature | Specification | | :--- | :--- | | **Sensing Method** | Retro-reflective | | **Sensing Distance** | 0.1 to 4 meters (with E39-R1 reflector) | | **Supply Voltage** | 10 to 30 VDC (includes 10% ripple) | | **Output Type** | NPN Open Collector | | **Output Mode** | Selectable: Light-ON / Dark-ON | | **Current Consumption** | 30 mA maximum | | **Response Time** | 2.5 ms maximum | | **Light Source** | Infrared LED (880 nm) | | **Housing Material** | Plastic (M18 cylindrical thread) | | **Connection** | Pre-wired cable (2m) | --- ### 2. Output Circuitry (NPN) The "C4" in the model name indicates an **NPN Output**. * **Load Switching:** In an NPN configuration, the sensor acts as a switch to the negative (0V) rail. * **Logic:** When the sensor is triggered, the black wire (output) is pulled down to the ground. * **Protection:** Most models in this series include short-circuit and reverse polarity protection to prevent damage from incorrect wiring. --- ### 3. Wiring Configuration The sensor typically uses a standard 3-wire color code: | Wire Color | Signal | Description | | :--- | :--- | :--- | | **Brown** | +Vcc | Positive power supply (10-30V DC) | | **Blue** | 0V / GND | Negative power supply | | **Black** | Output | NPN signal wire to PLC or Relay | --- ### 4. Key Components & Operation * **Emitter & Receiver:** Both are housed in the same M18 body. The emitter sends infrared light, and the receiver waits for it to bounce back from a reflector. * **Polarization (Optional):** Some E3F2 models include a polarizing filter to detect shiny (mirror-like) objects, though the standard R4C4 is optimized for general-purpose detection. * **Sensitivity Adjustment:** Usually features a potentiometer on the rear to adjust the sensing range or threshold. * **LED Indicators:** Equipped with an orange LED to indicate the output status and a green LED to indicate stability (power). ---