Introduced in 1979 by Schneider Electric (Modicon), the Modbus® fieldbus is an essential, open communication standard, supported by a large number of products and vendors on the market today.
With over 7 million nodes in North America and Europe alone, Modbus is the de facto standard in multi vendor integration.
In a typical Modbus network, messages are sent over an RS232/RS485 serial communication link (EIA standard). The Modbus protocol is based on a master/slave principle, eg. the master sends a request and the addressed slave sends back a response.
As Modbus is a protocol which is independent of the physical network layer, Modbus serial line can be integrated seamlessly into Modbus TCP networks, using simple gateways. This is transparent for the Client application.
- Up to 247 devices in one network
- Up to 1km network range
- Broadcast messaging supported
- Standard cabeling
A "de facto" standard and the most widely used network protocol in the industrial manufacturing environment
- Open communication standard
- Easy device integration at low cost
- Easy integration of new equipment to installed base
- Widely supported by SCADA and HMI software
- Wide distributed knowledge base
Các ứng dụng
- Modbus serial line can be used in virtually all applications. Examples reach from small low cost simple I/O devices to the configuration port and control of variable frequency drives. Actually Modbus serial line is used to collect data from distributed power meters.
- PLCs (Series 7, Series 1000, Modicon TSX Micro, Premium, Quantum, Momentum, Compact, Twido)
- Most Telemecanique devices