The **PM-R25-C3** is a subminiature, U-shaped photoelectric sensor manufactured by Panasonic (formerly Sunx). It is widely used in industrial automation for sensing the presence or position of thin objects, such as rotating disks, moving parts, or paper. --- ### 1. Technical Specifications The following table highlights the primary electronic and physical characteristics of the PM-R25-C3. | Feature | Specification | | :--- | :--- | | **Sensing Method** | Through-beam (U-shaped) | | **Sensing Distance** | 6 mm (fixed) | | **Output Type** | NPN Open-collector Transistor | | **Output Channels** | 2 outputs (Light-ON / Dark-ON) | | **Supply Voltage** | 5 to 24 V DC ±10% | | **Current Consumption** | 15 mA or less | | **Response Time** | 20 µs or less (under specific conditions) | | **Connection Type** | 3-meter attached cable (4-core) | --- ### 2. Key Electronic Components & Wiring The sensor operates using an infrared LED and a phototransistor positioned across a 6mm gap. #### **Output Configuration** The device features **Dual Outputs**, meaning you do not need to choose between Light-ON and Dark-ON models; both signals are available simultaneously: * **Output 1:** Conducts when the beam is received (Light-ON). * **Output 2:** Conducts when the beam is blocked (Dark-ON). #### **Wiring Diagram Logic** To integrate the PM-R25-C3 into a circuit, follow the standard color-coding for the 4-core cable: ```text Brown : +V (5 to 24V DC) Blue : 0V (GND) Black : Output 1 (Light-ON) White : Output 2 (Dark-ON) ``` --- ### 3. Physical Design Features * **R-Shape (R-Type):** The "R" in the part number indicates the cable exits from the side, allowing for flexible mounting in tight vertical spaces. * **Large Indicator:** Features a large, orange operation indicator that is visible from multiple angles, simplifying troubleshooting. * **M3 Mounting:** Uses standard M3 screws for secure installation on machine frames. --- ### 4. Common Applications * **Disc Encoder Reading:** Detecting slots in a rotating disk to determine speed or position. * **Limit Sensing:** Acting as an "End-of-Travel" stop for linear actuators. * **Object Detection:** Identifying the presence of a wafer, PCB, or paper edge in a processing line.