The **E3F2-R4C4F** is a high-performance photoelectric sensor produced by Omron. It belongs to the E3F2 series, which is known for its cylindrical M18 housing and robust sensing capabilities. --- ### ## Technical Specifications The "R4C4F" suffix defines the specific electrical and functional characteristics of this sensor: | Feature | Specification | | :--- | :--- | | **Sensing Method** | Retro-reflective (requires a reflector) | | **Sensing Distance** | 0.1 to 4 Meters (with E39-R1 reflector) | | **Output Type** | NPN Open Collector | | **Operation Mode** | Light-ON / Dark-ON (Selectable via wiring) | | **Power Supply** | 10 to 30 VDC | | **Housing Diameter** | M18 (18mm) | | **Connection** | Pre-wired (2-meter cable) | | **Current Consumption** | 30 mA max | | **Response Time** | 2.5 ms max | --- ### ## Internal Electronics and Wiring The sensor uses an NPN transistor output. This means when the sensor is triggered, it "sinks" the load to the negative (0V) rail. #### **Pinout / Wire Color Mapping** ```text Brown: +V (10-30 VDC) Blue: 0V (GND) Black: Output (Control Signal) White: Mode Selection (L-ON/D-ON) ``` #### **Output Circuit Configuration** The E3F2-R4C4F uses an **NPN Open Collector**. To interface this with a microcontroller (like an Arduino) or a PLC: 1. **Load Connection:** The load should be connected between the **Positive Supply** and the **Black wire**. 2. **Logic Level:** Because it is NPN, the signal will be "LOW" (0V) when the output is active. --- ### ## Key Electronic Features * **Built-in Amplifier:** The sensor contains an internal amplifier, meaning it does not require an external controller to process the light signal. * **Polarized Light:** It uses a polarized lens system to prevent "false positives" from shiny or metallic objects that are not the intended reflector. * **Protection Circuits:** * **Reverse Polarity Protection:** Prevents damage if wires are swapped. * **Short-circuit Protection:** Protects the NPN transistor from overcurrent. * **Mutual Interference Protection:** Allows two sensors to be mounted close to each other without cross-talk. --- ### ## Application Use Case Since this is a **Retro-reflective** sensor, it emits a light beam that must bounce off a reflector and return to the sensor head. If an object breaks this beam, the NPN output switches. It is commonly used in: * Conveyor belt counting. * Gate/Door automation. * Detection of transparent or opaque objects on production lines.