The **PM-U24-R** is a specific model of a U-shaped (slot) micro photoelectric sensor manufactured by **Panasonic** (formerly Sunx). It is widely used in industrial automation for sensing the presence of objects passing through its slot. --- ## 1. Technical Specifications Below are the primary electronic and physical specifications for the PM-U24-R: | Feature | Specification | | :--- | :--- | | **Sensing Method** | Thru-beam (U-shaped) | | **Sensing Range** | 6 mm (fixed) | | **Supply Voltage** | 5 to 24 V DC ±10% | | **Output Type** | NPN Open-collector transistor | | **Output Operation** | Light-ON / Dark-ON (Dual Output) | | **Response Time** | 20 µs or less under light received condition | | **Current Consumption** | 15 mA or less | | **Connection Type** | 3m Flexible Cable (indicated by the "-R" suffix) | --- ## 2. Key Electronic Components & Features ### A. The Optical Pair The device consists of two main electronic elements housed in the "U" shape: * **Emitter:** An Infrared LED that transmits a beam of light across the slot. * **Receiver:** A phototransistor that detects the presence or absence of that infrared beam. ### B. Output Configuration (NPN) The "NPN Open-collector" means the sensor acts as a switch to the **negative (GND)** rail. When triggered: 1. The output transistor closes. 2. It pulls the signal line down to 0V. 3. A load (like a PLC input or a Relay) should be connected between the **positive supply** and the **output wire**. ### C. The "-R" Suffix (Robotic/Flexible Cable) The "R" in the model name is electronically significant for durability. It indicates that the unit is equipped with a **vibration-resistant, flexible (robotic) cable**. This makes it suitable for: * Moving parts of machinery. * Robotic arms. * Applications with high-frequency bending. --- ## 3. Wiring Diagram (Typical) To integrate the PM-U24-R into a circuit, follow this standard color-coding: ```markdown Brown (+) : 5 to 24V DC Blue (-) : 0V / GND Black (OUT): Output 1 (e.g., Light-ON) White (OUT): Output 2 (e.g., Dark-ON) ``` --- ## 4. Protection Circuitry The PM-U24-R includes internal circuitry to ensure reliability in industrial environments: * **Reverse Polarity Protection:** Prevents damage if the power wires are swapped. * **Short-circuit Protection:** Protects the NPN transistor from excessive current if the output is accidentally grounded.