The **PM-R54** is a high-performance, U-shaped (slot) micro photoelectric sensor manufactured by **Panasonic (formerly Sunx)**. It is widely used in industrial automation for position sensing, limit detection, and counting. --- ## 1. Core Technical Specifications The following table outlines the primary electrical and mechanical characteristics of the PM-R54 sensor: | Feature | Specification | | :--- | :--- | | **Sensing Range** | 5 mm (Fixed) | | **Supply Voltage** | 5 to 24 V DC ±10% | | **Current Consumption** | 15 mA or less | | **Output Type** | NPN Open-Collector Transistor | | **Output Operation** | Dual Output (Light-ON / Dark-ON) | | **Response Time** | 20 μs or less (under specific conditions) | | **Peak Emission Wavelength** | Infrared LED (880 nm) | | **Protection Degree** | IP40 | --- ## 2. Pin Configuration and Wiring The PM-R54 typically features a 4-pin connector or cable system. Understanding the internal circuitry is crucial for preventing short circuits. ### Internal Circuit Diagram (NPN Type) ```text [V+] (Brown) -------[ + 5-24V DC ] [L] (Pink) -------[ Mode Selection: Connect to V+ for L-ON, Open for D-ON ] [Out] (Black) -------[ Load / PLC Input ] [0V] (Blue) -------[ Ground ] ``` ### Key Components: * **Emitter:** An Infrared (IR) LED that broadcasts a beam across the 5mm slot. * **Receiver:** A phototransistor that detects the IR beam. * **Output Transistor:** An NPN open-collector capable of sinking up to 50mA to 100mA (depending on the specific sub-model). --- ## 3. Physical Design and Dimensions The "R" in PM-R54 refers to the **R-shaped (Right-angle)** housing, which allows for specific mounting orientations that differ from the K, L, or U-type models in the same series. * **Slot Width:** 5 mm. * **Minimum Sensing Object:** Opaque objects as small as 0.8 x 1.8 mm. * **Indicator:** Includes a large, easy-to-see Red LED operation indicator that lights up when the output is active. --- ## 4. Application Advantages 1. **High Speed:** With a response time in the microseconds, it is ideal for high-speed motor shaft encoding or disk sensing. 2. **Vibration Resistance:** The internal electronics are potted to withstand industrial vibrations. 3. **Dual Outputs:** Having both Light-ON and Dark-ON outputs allows for flexibility in logic design without needing external inverters. ---