The **M2RTS-R-B1-R/UL** is a specialized industrial signal conditioner and transducer manufactured by **M-System (now MG CO., LTD)**. This specific model is a **Resistance Thermometer Transmitter** (RTD Transmitter). --- ## 1. Technical Specifications This device converts a signal from a Resistance Temperature Detector (RTD) into a standard DC output signal (e.g., 4-20mA or 0-10V). | Parameter | Specification | | :--- | :--- | | **Series** | M2 Series (Plug-in Signal Conditioners) | | **Input Type (R)** | RTD (JPt 100, Pt 100, etc.) | | **Output Type (B1)** | 4 – 20 mA DC (Internal resistance 750 $\Omega$ max) | | **Power Input (R)** | 24V DC | | **Standards (/UL)** | UL / cUL Class I, Div 2 Approval | | **Construction** | Plug-in style with socket base | | **Isolation** | Input to output to power | --- ## 2. Component Breakdown The part number follows a modular logic defined by the manufacturer: ### M2RTS - R - B1 - R / UL * **M2RTS**: The basic model code for a Resistance Thermometer Transmitter. * **R (Input)**: RTD input (Configurable for Pt 100, Pt 50, JPt 100, etc.). * **B1 (Output)**: Specific output code representing a 4–20 mA DC signal. * **R (Power)**: Indicates 24V DC operating voltage. * **UL**: Indicates the unit is certified for UL/cUL safety standards (critical for North American industrial installations). --- ## 3. Key Electronic Features * **Burnout Protection**: The device includes a "Burnout" feature. If the RTD wire breaks, the output will automatically drive to a high (upscale) or low (downscale) limit to signal a failure to the PLC/DCS. * **Linearization**: RTD resistance is not perfectly linear relative to temperature. This transmitter contains electronic circuitry to linearize the signal before converting it to milliamps. * **Three-Wire Compensation**: The electronics are designed to compensate for lead-wire resistance in 3-wire RTD setups, ensuring the length of the wire does not affect accuracy. * **Galvanic Isolation**: The device uses internal optocouplers or transformers to isolate the input (field side) from the output (control side), protecting sensitive PLC hardware from electrical surges or ground loops. --- ## 4. Connection Diagram Example Below is a conceptual representation of the wiring terminals: ```text [ FIELD SIDE ] [ DEVICE ] [ CONTROL SIDE ] RTD (Terminals) --------> [ M2RTS Unit ] --------> PLC / Controller 1, 2, 3 (Input) (Socket Base) Output (+ / -) | | [ 24V DC ] ``` ---