Protocols

What Is Modbus Protocol?

Modbus is the most widely used serial communication protocol in industrial automation systems. Developed by Modicon in 1979, this open standard enables data exchange between PLCs, sensors, and HMI devices.

How Does Modbus Protocol Work?

Modbus operates in a master-slave architecture. The master device (PLC, SCADA) reads from or writes to slave devices (sensors, drives). Modbus RTU communicates over serial port (RS-485), while Modbus TCP communicates over Ethernet. Each slave has a unique address. Data is organized as coils (bits), discrete inputs, holding registers, and input registers.

Where Is Modbus Protocol Used?

PLC and HMI communication

Energy analyzer reading

Motor drive control

Temperature and humidity sensors

SCADA system integration

Building automation systems

What Are the Advantages of Modbus Protocol?

Open and free standard

Simple implementation

Broad device support

Reliable and proven

RTU and TCP options

Easy troubleshooting

Olivenet's Modbus Protocol Solutions

Olivenet IoT gateways connect your existing industrial equipment to cloud platforms with Modbus RTU and TCP support. Modbus integration plays a critical role in our retrofit projects.

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Related Terms

Keywords

modbusmodbus rtumodbus tcprs485industrial protocol