The **M2RTS-R-A1D-R2/Q** is a high-precision, plug-in type RTD (Resistance Temperature Detector) transmitter belonging to the **M2 Series** by M-System (now MG CO., LTD.). It is designed to convert signals from an RTD into a standard process signal (DC voltage or current). --- ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Model Type** | RTD Transmitter (Programmable/Fixed) | | **Input Type** | RTD (Pt 100, JPt 100, etc.) | | **Output Type** | DC Current or Voltage (Standardized) | | **Power Input (R)** | 24V DC | | **Accuracy** | ±0.1% of span | | **Response Time** | ≤ 0.5 seconds (0 – 90%) | | **Isolation** | 3-way isolation (Input to Output to Power) | | **Construction** | Plug-in base socket | --- ### 2. Part Number Breakdown (Nomenclature) Understanding the suffix codes helps identify the specific electronic configuration: * **M2RTS**: Base model series (RTD Transmitter). * **-R**: Power Input. `R` typically denotes **24V DC**. * **-A**: Input Signal. `A` signifies **Pt 100 (ITS-90)**. * **1**: Output Signal. `1` usually represents **4 – 20mA DC**. * **-D**: Power Supply variation or specific hardware revision. * **-R2**: Specific wiring or housing enhancement (common in M2 series for base-mount compatibility). * **/Q**: Special Option. This indicates the unit has **customized factory settings** or specific certifications (e.g., specific scaling or coating). --- ### 3. Electronic Functional Components The device consists of three primary internal stages: #### A. Input Conditioning Stage Uses a **3-wire or 4-wire bridge circuit** to measure the resistance change of the RTD. It includes burnout protection logic; if the RTD wire breaks, the transmitter will drive the output to a specific "upscale" or "downscale" limit. #### B. Isolation & Conversion (The "Core") The signal is passed through an **Optical or Magnetic Isolator**. This prevents ground loops and protects sensitive PLC/DCS equipment from high-voltage surges on the field side. It converts the non-linear resistance curve of the RTD into a linear electronic signal. #### C. Output Drive Stage A high-precision operational amplifier (Op-Amp) circuit converts the internal signal into a robust **4-20mA current loop** or voltage signal capable of driving long-distance cabling to a controller. --- ### 4. Installation & Wiring The unit is a **Plug-in style**, meaning the electronics are housed in a removable module while the wiring stays attached to a permanent base socket. This allows for "hot-swapping" or easy maintenance without disturbing the field wiring. ---