Protocols
Modbus
The most widespread industrial fieldbus
Official spec ↗Modbus
Modbus is the world's most widespread industrial communication protocol: born in 1979 for Modicon PLCs, it remains the common language of sensors, drives and meters on the plant floor. It runs in two main variants: Modbus RTU (over serial RS-485/RS-232) and Modbus TCP (over Ethernet/IP).
Its model is master-slave (client-server over TCP): the master reads and writes the slaves' registers. It is simple, open and universally supported, making it the first choice to integrate heterogeneous equipment in SCADA and IIoTITermIIoT (Industrial IoT)IIoT (Industrial IoT) is the application of IoT to industrial environments (manufacturing, energy, logistics), with strict reliability and latency requirements.View profile.
Compatible devices
- PLCs and industrial controllers
- Variable-frequency drives
- Energy meters and plant-floor sensors





