The **M2RTS-S-AB-R2/N** is a specific model within the M2RTS series of **RTD (Resistance Temperature Detector) Transmitters**. These devices are used to convert the small resistance changes from a temperature sensor (like a Pt100) into a standardized industrial signal (like 4-20mA or 0-10V). --- ### 1. Component Breakdown (Model Code Analysis) The alphanumeric string provides specific details about the internal electronic configuration: | Segment | Meaning | Specification | | :--- | :--- | :--- | | **M2RTS** | Series Name | Compact RTD Transmitter (Plug-in Type) | | **S** | Output Type | Standard DC output (Current/Voltage) | | **AB** | Input/Output | **A:** Pt 100 (3-wire) / **B:** 4–20 mA DC | | **R2** | Power Supply | 100 – 120V AC (Standard utility power) | | **N** | Option | Standard version (No special coating or options) | --- ### 2. Core Electronic Specifications This transmitter utilizes several key electronic stages to ensure accuracy and isolation. * **Input Stage:** Designed for a 3-wire Pt100 RTD. It includes a constant current source to excite the sensor and bridge circuitry to compensate for lead wire resistance. * **Isolation:** The "R2" model typically features **3-way isolation**. This means the Input, Output, and Power circuits are electrically separated (usually up to 2000V AC), preventing ground loops and protecting the PLC/Controller. * **A/D and D/A Conversion:** Modern M2RTS units use a microprocessor-based system where the analog resistance is digitized, linearized (to correct for the RTD's non-linear curve), and then converted back to a precise 4-20mA analog output. --- ### 3. Electrical Connections The unit is typically a plug-in style that fits into a specialized base. | Terminal No. | Function | Description | | :--- | :--- | :--- | | **1 - 2** | Output (+) / (-) | 4-20mA DC Signal to PLC | | **3 - 4** | Power Supply | 100-120V AC Input | | **5, 6, 7** | Input (A, B, b) | Connections for the Pt100 RTD | --- ### 4. Technical Performance Constants * **Accuracy:** Generally $\pm 0.1\%$ of span. * **Temperature Coefficient:** $\pm 0.015\%$ per degree Celsius. * **Response Time:** $\leq 0.5$ seconds (0 to 90%). * **Burnout Protection:** If the RTD wire breaks, the electronics are programmed to drive the output to "Upscale" (over 20mA) to alert the system of a failure. ---