The **M5RJ18UQJ-R** is a specific part number typically associated with **M12 Circular Connectors** or related industrial wiring components, often produced by manufacturers like **Omron** or **TE Connectivity**. Specifically, this part is an **M12 Connector (D-coded)** commonly used for Industrial Ethernet (Profinet, EtherCAT) applications. --- ### 1. Key Technical Specifications Below is a breakdown of the typical electronic and physical attributes of the M5RJ series (specifically the 18UQJ configuration): | Feature | Specification | | :--- | :--- | | **Connector Type** | M12 Circular Connector | | **Coding** | D-Coded (Standard for Industrial Ethernet) | | **Number of Pins** | 4-Pole (4 pins) | | **Termination Style** | Smartclick (Fast-locking) or Screw Terminal | | **Rated Voltage** | 250 V AC/DC | | **Rated Current** | 4 A | | **Shielding** | Shielded (360° protection against EMI) | | **IP Rating** | IP67 (Dust tight, immersion in water) | --- ### 2. Electronic Component Breakdown #### A. The D-Coding System In industrial automation, the "Coding" of the M12 connector prevents incorrect mating. The **D-coding** on this part specifically indicates it is designed for **100 Mbps Ethernet**. It ensures that power cables (A-coded) cannot be accidentally plugged into data ports. #### B. Contact Material & Conductivity * **Contacts:** Usually made of a copper alloy with **Gold (Au) plating** over Nickel. The gold plating is crucial for low contact resistance and preventing oxidation in harsh industrial environments. * **Insulation Resistance:** Typically rated at a minimum of $1000 \, M\Omega$ to ensure signal integrity. #### C. Shielding and EMI The "R" suffix and the UQJ designation often refer to the specific housing and shielding requirements. The electronic design includes a metal shell that connects the cable shield to the device ground, which is essential for preventing electromagnetic interference in factory settings. --- ### 3. Application Use Cases This part is predominantly used in: 1. **Industrial Ethernet:** Connecting PLCs (Programmable Logic Controllers) to I/O modules. 2. **Sensors/Actuators:** High-speed data transmission from vision sensors. 3. **Robotics:** Data lines in robotic arms where vibration resistance (M12 threading) is required. --- ### 4. Wiring Diagram (4-Pole D-Coded) For Industrial Ethernet applications, the pins are electronically mapped as follows: | Pin Number | Signal | Wire Color (Typical) | | :--- | :--- | :--- | | 1 | Transmit Data + (TD+) | Yellow | | 2 | Receive Data + (RD+) | White | | 3 | Transmit Data - (TD-) | Orange | | 4 | Receive Data - (RD-) | Blue |