The **M2AC-A21-R/CE** is a high-precision digital signal converter (transducer) manufactured by **M-System**. This specific model is designed to convert an alternating current (AC) input into a standard analog DC output, typically used in industrial automation and power monitoring systems. --- ## 1. Technical Specifications The model name follows a specific nomenclature that defines its electronic capabilities: | Component | Code | Description | | :--- | :--- | :--- | | **Model** | M2AC | AC Current Transmitter (RMS sensing) | | **Input** | A | 0 – 5 A AC | | **Output** | 2 | 0 – 5 V DC | | **Power Input** | 1 | 100 – 120 V AC | | **Option** | R | High-accuracy / Response time options | | **Standard** | CE | CE Marking (European Conformity) | --- ## 2. Key Electronic Features ### RMS Sensing Unlike average-sensing devices, the M2AC uses **True RMS** (Root Mean Square) conversion. This allows the part to accurately measure distorted waveforms, which is critical when dealing with electronic equipment that generates electrical noise or harmonics. ### Signal Isolation The device provides a high level of isolation between the input, output, and power supply. This protects downstream PLCs or SCADA systems from high-voltage surges or ground loops. * **Isolation Resistance:** 100 MΩ or more with 500 V DC. * **Dielectric Strength:** 2000 V AC @ 1 minute. ### Physical & Installation Parts * **Housing:** Flame-resistant resin (Black). * **Connection:** M3.5 screw terminals (nickel-plated steel). * **Mounting:** DIN rail or surface mounting. * **Zero/Span Adjustment:** Accessible on the front panel (±5% range). --- ## 3. Circuit Block Diagram (Simplified) The internal electronics operate in four main stages: 1. **Input Stage:** Uses a step-down transformer to safely scale the 5A AC current. 2. **Conversion Stage:** An RMS-to-DC converter circuit processes the waveform. 3. **Isolation Stage:** Optical or magnetic coupling transfers the signal across the isolation barrier. 4. **Output Stage:** An operational amplifier (Op-Amp) conditions the signal to a stable 0–5V DC output. ---