## Overview of the Panasonic (formerly SUNX) PM-R45 The **PM-R45** is a R-shaped (Right-angle) u-shaped photoelectric sensor commonly used in automation for position sensing, limit detection, and counting. It belongs to the **PM-45 series** of micro-photoelectric sensors. --- ### 1. Key Technical Specifications The following table highlights the primary electronic and physical characteristics of the PM-R45: | Feature | Specification | | :--- | :--- | | **Sensing Distance** | 6 mm (fixed) | | **Sensing Object** | Opaque object (min. 0.8 x 1.2 mm) | | **Supply Voltage** | 5 to 24 V DC ±10% | | **Current Consumption** | 15 mA or less | | **Output Type** | NPN or PNP Open-collector (model dependent) | | **Response Time** | 20 μs or less (under light received) | | **Operating Indicator** | Orange LED (lights up when light is received) | --- ### 2. Internal Electronic Structure The sensor operates using a pair of infrared components housed in a plastic U-shaped frame: * **Emitter:** An Infrared LED that constantly emits a beam across the 6mm gap. * **Receiver:** A phototransistor that detects the presence of the infrared beam. * **Output Logic:** Most PM-R45 models feature **dual outputs**: 1. **Light-ON:** Output is active when the beam is uninterrupted. 2. **Dark-ON:** Output is active when an object blocks the beam. --- ### 3. Wiring and Pin Configuration The sensor typically uses a 4-pin connector or a 4-wire cable. Below is the standard wiring diagram for the NPN version: ```mermaid graph LR A[Brown: +V 5-24V DC] B[Pink: Control Input / L-ON] C[Black: Output] D[Blue: 0V / GND] ``` #### Wiring Details: 1. **Brown:** Positive power supply. 2. **Blue:** Ground. 3. **Black:** Output signal (connected to the PLC or Load). 4. **Pink:** Mode selection. Connecting this to Ground or Power (depending on the specific sub-model) toggles between Light-ON and Dark-ON operations. --- ### 4. Mechanical Design (R-Shape) The "R" in PM-R45 designates the **Right-angle** physical profile. This is electronically identical to the PM-K45 (K-shape) or PM-L45 (L-shape), but the mounting holes and cable exit are oriented to allow the sensor to be mounted flat against a surface while the U-channel sits perpendicular. ---