Voltage measurement transducer, three-phase, with Modbus RTU output MAX-MB-3U-1

Three-phase voltage measurement transducer with Modbus RTU output

This is an advanced transducer designed for precise voltage measurement in three-phase systems. Thanks to the Modbus RTU interface, the device enables easy integration with automation and monitoring systems, transmitting voltage data in real time. It is a key element in installations requiring remote reading and analysis of electrical parameters.

Application and functionality

The MB-3U-1 transducer measures the TrueRMS effective voltage value, ensuring high measurement accuracy even for distorted waveforms. AC voltage measurement is performed against the neutral wire (N), while DC voltage measurement is performed against a common power supply point or GND. It is important to remember that the measurement channels are not galvanically isolated from each other, but are isolated from the power supply input and the RS-485 communication port. This ensures safety and reliable operation in various environmental conditions.

Communication and configuration

The transducer communicates via the MODBUS RTU protocol through the RS-485 port, offering a wide range of configuration settings – from transmission speed (1200 to 115200 bit/s) to data bits, stop bits and parity configuration. The device address can be set in the range of 1 to 247, allowing multiple transducers to be connected to a single system. LEDs indicate power supply (green **U** LED) and correct data exchange (yellow **Tx** LED), facilitating diagnostics and servicing.

Construction features and mounting

The device is designed for mounting on a 35 mm rail and occupies only 1 module (18 mm wide). Screw terminals with a cross-section of 2.5 mm² ensure safe and durable wire connections, and the tightening torque is 0.4 Nm. The IP20 protection degree guarantees protection against accidental contact and the ingress of solid objects larger than 12.5 mm. The transducer operates at a rated frequency of 50 Hz and has a voltage measurement range of up to 285 V AC.