AMS Device Manager, Hart over Profibus comms

I have been installing AMS Device Manager at a customer site using Hart over Profibus (T+H xEPI modules) interfacing with Delta V and Stahl remote I/O.  I have successfully managed to establish comms with the Hart devices and I am able to work with them online. In fact it works very well.  My problem is that establishing comms is inconsistent.  It take me about 1 in 10 attempts to make the connection whenever I rebuild Hierarchy on the device manager server plus station.  I obviously cannot accept this as a satisfactory install and was therefore wondering whether anyone else has come across such an issue. The versions I am using for all hardware and software should be compatible i.e. Delta V 10.3.1  Device Manager  V12.0.  In the Set Bus Parameters of the T+H software I am using the dafault PB settings.  When using a bench test setup of the system I didn't have this problem.  Any thoughts/advice would be appreciated.


  • Hello Ian,

    Thanks so much for your question. I am moving this post to our very active DeltaV community where you should receive a more timely response. When you have a question, comment, or thoughts specific to an industry or technology, it is best to post them in that group, rather than the general discussion area. You can join our DeltaV group here:

    Please let me know how we can improve your 365 experience in any way.


    Rachelle McWright

    Community Manager: Emerson Exchange 365

    Best Regards,

    Rachelle McWright | Community Manager, Emerson Exchange 365

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  • Ian,

    I have installed many Hart over Profibus gateway nodes across different manufacturing sites within my company.  I agree that the interface is very robust once you get it up and running.  It is also sometimes challenging to establish the communications for the first time.  I have found the following items to consider can be helpful.

    The DeltaV Profibus card needs to have a firmware version > 1.37 (testing my memory)

    There was a new verson of TACC software issued for AMS version 12.0.  TACC

    There was also another TACC upgrade for version 12.5.  TACC

    I have the best luck with droping the Profibus segment baud rate from 1.5 MBit/sec to 500 Kbit/sec.

    In most instances, I have also used the default DP settings.  In some cases it helped to set the Profile to user defined and increase the Ttr.

    Test with 70,000, 80,000 or 100,000.

    I have found that the following procedure works most of the time to establish communications.

    1.  Pull and reset DeltaV Profibus IO card  (pull out of IO rack for about 15 seconds, can be challenging depening on state of process)

    2.  Reset T+H gateway (Make a programming change to each unit that requires a reset, or cycle power)

    3.  Rerun Set Bus Parameter program (I removed the existing device and use the search function to add the new hardware.  Then I configured and activated it)

    4.  Rebuild Hierarchy in AMS Device Manager

    Rob Sentz

  • In reply to Robert Sentz:

    Rob thanks for your advice.  I changed the default Ttr setting in the "set bus parameter" application from the default 23735 to your suggested 70000.  The fault cleared straight away. The devices now connect without plugging in and out modules and connectors.  I now need to investigate what the optimum setting should be and whether or not the Ttr will need to alter as I build my database (up to 20 T+H units).

    Your advice was very much appreciated and helped solve a pressing problem.


    Ian Campbell

  • In reply to Rachelle McWright:

    Rachelle thanks for your help.  Got a reply within a couple of days as you can see from Rob and better still he solved my problem. Now joined the Delta V group.

    Much appreciated

    ian Campbell