Modbus is a serial communication protocol originally published by Modicon (now Schneider Electric) in 1979 for use with Programmable Logic Controllers (PLCs). Due to its open standard, simple implementation, and robust performance, it has become a de facto standard in the industrial electronics field.
Communication Architecture
Communication Architecture Modbus operates on a master-slave architecture (referred to as client-server in Modbus TCP). A master device, such as a host PC or PLC, sends a request to a slave device, which processes the request and returns a response. For example, a master controller can use specific function codes to read or write values to a power supply's memory registers, controlling voltage settings or monitoring current output.
Common Implementations
- Modbus RTU: The original and most common implementation, typically used over serial lines such as RS-485 or RS-232.
- Modbus TCP: Encapsulates Modbus data packets within TCP/IP frames, allowing communication over standard Ethernet networks.
Because of its widespread adoption, many Matsusada Precision programmable power supplies offer a Modbus interface, making them easy to integrate into existing industrial control systems and automated test environments.