I want to do profibus communication with third party system. I am using redundant AC800M controller PM866 with CI854A. Both side will be Profibus master so shall i use profibus DP-DP coupler in between CI854 & Third party. Also Can Profibus communication be redundant, How will be the connection.
Yes profibus DP DP coupler can be used. I have used Siemens DP DP coupler before, for redundancy you need two couplers one for each Profibus line. Check https://forum-controlsystems.abb.com/... for additional info.