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Automation Control | Networks & Communication | Modbus Message Protocol

 

Modbus

 
MODBUS Protocol

The Modbus protocol was introduced over twenty five years ago to revolutionise industrial communications, and today it remains the standard protocol for open, reliable industrial control as well as the cornerstone of our industrial Ethernet TCP/IP offer, Transparent Ready.

The MODBUS protocol is a message handling structure introduced by MODICON in 1979 to connect PLCs to programming tools. Today, this protocol is mainly used to set up master/slave or client/server type communications with between intelligent devices.
MODBUS is independent of the physical layer. It can be implemented on RS232, RS422, or RS485 links as well as on a wide variety of other media or any device that supports the TCP/IP protocol stack.

Modbus over TCP/IP is a completely open Ethernet protocol. The development of a connection to Modbus TCP/IP requires no proprietary component or license purchase. The protocol may be easily combined with any device that supports a standard TCP/IP communication stack. Specifications can be obtained free of charge from the modbus website.

• It is scalable in complexity

A device which has only a simple purpose need only implement one or two message types to be compliant.

• It is highly scalable in scope

A collection of devices using Modbus/TCP to communicate can range up to 10,000 or more on a single switched Ethernet network.

• It is simple to administer and enhance

There is no need to use complex configuration tools when adding a new station to a Modbus/TCP network.


• There is no vendor-proprietary equipment or software needed

Any computer system or microprocessor with Internet style (TCP/IP) networking can use MODBUS/TCP.

• It is very high performance

Limited typically by the ability of the computer operating systems to communicate. Transaction rates of 1000 per second or more are easy to achieve on a single station, and networks can be easily constructed to achieve guaranteed response times in the millisecond range.

• It is easily integrated
It can be used to communicate with the large installed base of Modbus devices, using conversion products which require little or no configuration.

Go to the Modbus website >>
   
 
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For more info download the Transparent Ready - User Guide (9.3Mb)
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