The **M2RTS-S-AE-R/UL** is a high-precision, industrial-grade **Signal Conditioner (Transmitter)** manufactured by M-System. It is specifically designed to accept a resistance thermometer (RTD) input and convert it into a standardized isolated DC output signal. Below is the detailed breakdown of its electronic components and specifications. --- ### 1. Key Technical Specifications | Feature | Description | | :--- | :--- | | **Input Type** | Resistance Thermometer (RTD) - typically Pt 100 or JPt 100 | | **Output Type** | DC Voltage or Current (selectable via model code) | | **Configuration** | **S:** Single Output | | **Power Input** | **R:** 24V DC | | **Standards** | **UL:** UL/C-UL Class I, Division 2 approval | | **Isolation** | 3-way isolation (Input to Output to Power) | --- ### 2. Functional Block Diagram Components The device operates through four primary electronic stages: 1. **Input Conditioning Stage:** * Uses a 3-wire bridge circuit to compensate for lead wire resistance. * Features **Burnout Protection**: A high-resistance pull-up/down circuit that forces the output to a safe state (max or min) if the RTD sensor wire breaks. 2. **Amplification & Linearization:** * Since RTD resistance is not perfectly linear with temperature, the internal circuitry applies **Linearization** to ensure the output corresponds accurately to the temperature scale. 3. **Isolation Barrier:** * Utilizes photocouplers or transformers to provide galvanic isolation. This prevents ground loops and protects sensitive PLC/DCS inputs from high-voltage surges on the field side. 4. **Output Stage:** * A precision operational amplifier (Op-Amp) drives the final DC signal (e.g., 4-20mA or 1-5V). --- ### 3. Electronic Features & Performance * **Response Time:** Typically $\leq 0.5$ seconds (0 to 90%). * **Temperature Coefficient:** $\pm 0.015\% / ^\circ\text{C}$ of max span, ensuring stability in fluctuating environments. * **Dielectric Strength:** 2000V AC @1 minute (Input to Output to Power to Ground). * **Zero/Span Adjustment:** Located on the front panel, these potentiometers allow for fine-tuning the calibration ($ \pm 5\%$ range). --- ### 4. Terminal Connections The device typically uses a socket-type base for easy maintenance. | Terminal | Function | | :--- | :--- | | **1 - 2 - 3** | RTD Input (A, B, B' terminals) | | **4 - 5** | DC Output (+) and (-) | | **7 - 8** | Power Supply (24V DC) | ---