The **M2RTS-R-D4-M2/UL** is a high-precision, plug-in type RTD (Resistance Temperature Detector) transmitter from the **M2 Series** by M-System. It is designed to convert signals from an RTD sensor into a standard industrial DC output signal. ### 1. General Specifications The model name can be broken down to understand its core electronic capabilities: | Component Code | Description | | :--- | :--- | | **M2RTS** | Model series (RTD Transmitter) | | **R** | Power Input: 24V DC | | **D4** | Input Signal: Pt 100 (ITS-90) | | **M2** | Output Signal: 4 – 20 mA DC | | **UL** | Certification: UL/C-UL Class I, Div 2 approved | --- ### 2. Key Electronic Features #### A. Input Circuit (RTD Interface) The device is designed to interface with a 3-wire RTD (typically Pt 100). - **Burnout Protection:** It includes circuitry to detect a broken sensor wire. If a wire breaks, the output will typically go to an upscale limit (above 20mA) or downscale limit to alert the control system. - **Excitation Current:** The transmitter provides a small, constant current to the RTD to measure resistance without causing significant self-heating. #### B. Isolation Technology This unit features **Three-way Isolation**: 1. **Input to Output** 2. **Input to Power** 3. **Output to Power** *Electronic Significance:* This prevents ground loops, protects sensitive PLC/DCS inputs from high-voltage surges, and reduces electromagnetic interference (EMI). #### C. Performance Characteristics | Parameter | Specification | | :--- | :--- | | **Accuracy** | ±0.1% of span | | **Response Time** | ≤ 0.5 seconds (0 – 90%) | | **Temperature Coefficient** | ±0.015% / °C | | **Insulation Resistance** | 100 MΩ minimum with 500V DC | --- ### 3. Connection Diagram (Internal Logic) ```mermaid graph LR A[RTD Sensor] --> B(Input Circuit) B --> C{Isolation Barrier} C --> D(Signal Conditioning) D --> E[4-20mA Output] F[24V DC Power] --> C ``` --- ### 4. Physical and Installation Aspects - **Mounting:** DIN Rail plug-in base. This allows the electronic module to be replaced without disconnecting the field wiring. - **Adjustments:** Zero and Span adjustments are located on the front panel, allowing for fine-tuning of the electronic output relative to the temperature input. - **Housing:** Flame-resistant black resin.