Ethernet/IP vs OPC and Modbus

Apples and oranges maybe.

Here is a link for the overview of OPC: http://opcfoundation.org/DownloadFile.aspx?CM=3&RI=1&CN=KEY&CI=282&CU=4

Ethernet is a wiring standard, IP is Internet Protocol.

Modbus can be encapsulated in IP or can be a serial interface.

Thanks for your reply....

But I want details on difference between OPC, Modbus and Ethernet /IP i.e. Ethernet based Industrial Protocol (I=Industrial and P=Protocol) which is CIP (Common Industrial Protocol)based.

Please share if you have some valuable information.

Regards,

Skasnl

Resources:

http://en.wikipedia.org/wiki/EtherNet/IP

http://en.wikipedia.org/wiki/Modbus

http://en.wikipedia.org/wiki/OLE_for_process_control

EtherNet/IP and Modbus are different communications protocols, while OPC is a standards specification.

You may have Ethernet IP and Modbus at one site if they are connected by a gateway. So, you don't have to choose just one or the other. To make Modbus RTU slaves available as Ethernet IP, you can use a gateway like this: http://www.icpdas-usa.com/products2.php?PID=3811

Modbus is normally a master -slave communication. Used normally in Control system communication over a very short distance. Digital signals or logical 1's and 0's are transmitted over the particular adresses.

OPC is OLE for Process control.OLE stands for object linking and Embedding. This is an open source communication. The communication is established by developing pipelines between the Client and the Host systems.

Ethernet uses TCP/IP communication methodology. It is possible to transfer large data.

And it is not a master slave communication. Transmission and reception happens together. It is a widely used method of communication but it has a disadvantages of long distance communications. Nowadays we have industrial ethernet communication as well..Any way for other long distance communication we can rely on Fiberoptics or wireless communications.

Cheers,

Shan