The **M2MST-0-R2/CE** is a specialized electronic signal conditioner and transducer module manufactured by **M-System**. It is primarily used in industrial automation to convert a thermocouple input into a standardized DC output signal while providing electrical isolation. --- ### ## Technical Specifications The following table highlights the core electronic characteristics of the device: | Feature | Specification | | :--- | :--- | | **Input Type** | Thermocouple (Types K, E, J, T, B, R, S, C) | | **Output Type** | 4 – 20 mA DC (Current Loop) | | **Power Input (R2)** | 11 – 27 V DC | | **Isolation** | 3-Way (Input to Output to Power) | | **Mounting** | DIN Rail Mounting | | **Response Time** | ≤ 0.5 seconds (0 – 90%) | | **Cold Junction Comp.** | Built-in (Integrated CJC sensor) | | **Safety Standard** | CE Marking (EMC Directive) | --- ### ### Key Electronic Components & Functions 1. **Analog-to-Digital Conversion (ADC):** The module takes the millivolt (mV) signal generated by a thermocouple and digitizes it. It uses high-resolution conversion to ensure precision even with the non-linear voltage curves of thermocouples. 2. **Cold Junction Compensation (CJC):** Since a thermocouple measures the temperature difference between the "hot" junction and the terminal "cold" junction, the electronic board includes a thermistor or semiconductor sensor at the input terminals to compensate for ambient temperature fluctuations. 3. **Galvanic Isolation:** The "R2" designation implies a specific power requirement, and the internal circuitry uses transformers or optocouplers to isolate the power supply, input, and output. This prevents ground loops and protects sensitive PLC/DCS equipment from high-voltage surges on the sensor side. 4. **Signal Linearization:** Thermocouples are inherently non-linear. The internal microprocessor applies a mathematical curve-fit to the raw mV signal so that the 4-20mA output is perfectly linear to the temperature range. 5. **Burnout Protection:** In the event of a wire break (thermocouple failure), the electronic circuit is designed to drive the output to a specific state (usually Upscale/20mA+ or Downscale/4mA-) to alert the control system of a fault. --- ### ### Wiring Configuration | Terminal No. | Function | Description | | :--- | :--- | :--- | | **1 - 2** | Input (+) / (-) | Thermocouple wire connections | | **4 - 5** | Output (+) / (-) | 4-20mA Signal to PLC/Controller | | **7 - 8** | Power (+) / (-) | 24V DC Supply |