The **M2VT-BC-R2** is a high-performance **V/I Converter (Voltage-to-Current Signal Conditioner)** from the M2-Series manufactured by **M-System**. It is designed to convert a DC voltage input signal into a proportional standard DC current output signal, providing galvanic isolation between the two. --- ### 1. Technical Specifications Table | Feature | Specification | | :--- | :--- | | **Model Series** | M2VT (Plug-in Signal Conditioner) | | **Input Signal** | 0 – 10V DC (Standard for -BC- model) | | **Output Signal** | 4 – 20mA DC | | **Power Input (R2)** | 11 – 27V DC (Ripple 10% p-p max) | | **Accuracy** | ±0.1% of span | | **Isolation** | 3-way isolation (Input to Output to Power) | | **Response Time** | ≤ 0.5 seconds (0 – 90%) | | **Construction** | Plug-in base (Easy maintenance) | --- ### 2. Key Electronic Components & Internal Functions The device functions through several internal electronic stages to ensure precision and signal integrity: #### A. Input Stage (Voltage Buffer) The input stage uses high-impedance operational amplifiers (Op-Amps) to sense the voltage signal (0-10V) without loading the source circuit. This stage often includes low-pass filtering to remove high-frequency noise from the input line. #### B. Isolation Barrier (Optical/Magnetic) To prevent ground loops and protect sensitive equipment, the M2VT uses **3-way isolation**. * The signal is typically chopped into a high-frequency AC signal, passed through a transformer or optoisolator, and then reconstructed on the output side. * This protects the PLC/DCS from surges on the field side. #### C. Constant Current Output Drive The "BC" designation indicates the conversion to a current loop (4-20mA). The internal electronics act as a **controlled current source**, adjusting the output voltage automatically to maintain the correct milliamps regardless of the load resistance (up to a specific limit, usually 750Ω). #### D. Power Regulation (R2) The "R2" suffix identifies the power circuit designed for **24V DC nominal**. It includes: * Reverse polarity protection. * Voltage regulators to ensure internal Op-Amps receive stable DC despite fluctuations in the main 24V supply. --- ### 3. Connection Diagram Overview | Terminal No. | Function | Description | | :--- | :--- | :--- | | **1** | Output (+) | 4-20mA Positive | | **2** | Output (-) | 4-20mA Negative | | **4** | Power (U) | +24V DC | | **5** | Power (V) | 0V DC (Ground) | | **7** | Input (+) | 0-10V Positive | | **8** | Input (-) | 0-10V Negative | --- ### 4. Summary of Benefits * **Noise Immunity:** By converting voltage to current (4-20mA), the signal can travel long distances without voltage drop or interference. * **Safety:** 2000V AC isolation between terminals prevents electrical damage from spreading. * **Maintenance:** The plug-in socket design allows the electronic module to be replaced without disconnecting the field wiring.