good choice for fieldbus application


Thread Starter


I need your help to choice the best fieldbus solution to connect :

-from 2 to 100 microPLC (each must be able to work disconnected
-fieldbus failure-)
-some HMI stations which can be connect and disconnect anyway to
access to each PLC directly or by the fieldbus

Actually some PLC have modbus connection

The speed of the fielbus is not critical (very slow process)

A must : the possibility to connect a web server to acces to the process
by a web navigator.

Thanks for your helps.

Kirk S. Hegwood

Check out You could use their WinPLC which are connected via Ethernet and their EZ Touch HMI's which I believe are Ethernet capable as well. The software would be Think&Do which is Windows based and has the drivers that would allow you to connect to a web server. Fast, simple and inexpensive.

Kirk S. Hegwood
Signing for Hegwood Electric Service, Inc.
[email protected]

All these features and more are available on DeviceNet. Remember that Ethernet has different application layers, thus 2 types of PLC'S may not be able to communicate with each other even though they share the same cable. If you want an open deterministic system, then DeviceNet and Ethernet/IP is the solution. Check out these 2 sites. and