Calculating Foundation Fieldbus Segment Loading

When engineering a project with Foundation fieldbus, one element to consider is the electrical loading on each segment. I received an email the other day asking:

…to find required formulas to calculate FOUNDATION FIELD BUS loading… I am using [brand X] product and I have come across a web site that you can provide information. If you have those formulas… it would be nice if you could share them.

I also did some Googling around, and saw a few things, but did not see our Emerson Segment Design Tool listed in the search results, at least not in the first few pages. The segment design tool development team released version 5 of this tool in September, just before the Emerson Exchange meeting.

Here’s a bit about what this calculator tool does:
Emerson Foundation Fieldbus Segment Design Tool
The Segment Design Tool is a Windows 98/NT/W2K/XP compatible program designed to provide a general guide for reducing the time required to engineer a Foundation fieldbus H1 segment for the DeltaV system, Ovation system and the Rosemount 3420 Fieldbus Interface. The Segment Design Tool checks the segment layout utilizing the Fieldbus Foundation‘s guidelines governing cable lengths, power consumption and proper segment termination. This tool now supports a variety of hazardous area protection techniques, including FISCO, FNICO and Entity Concept for Intrinsic Safety.

One of Emerson’s Fieldbus consultants, Dan Daugherty, whom you may recall from earlier posts, helped me find the URL for this tool. He also added this bit of wisdom that I passed back to the person who originally emailed me:

My advice for people who can’t find an exact match in the Segment Design Tool’s component library for their cable or other components is to find something close and then use enough design margin that it won’t matter if it isn’t exact.

I’ll also pass along that the segment design tool team invites comments and questions. Feel free to take them up on their offer, or leave a comment on this post, and I’ll pass it along to the team.

Posted Tuesday, November 20th, 2007 under Foundation Fieldbus, Interoperability, Support Services.

6 comments

  1. RATANPARA YOGESH P says:

    Kindly, Send the Required Detail for the Calculation of the fIELD BUS lOAD

  2. John ODonnell says:

    Please send me segment loading tool

  3. how about that? says:

     Hello. Sorry to be offtopic but i wonder what are the things an engineer that works in Process Systems and Solutions should know? And when i ask i am asking hoping that i would get a concrete answer. How about physics? What exactly? Kirchoff and thermodynamics? What about chemistry? What should i know from that? PID regulators i know that are a must. DCS’s too. But further than that i don’t know what to learn. Thank you and hope to get an answer fast 😀 my interview is comming really fast and i’m really excited about it. I want to learn as many stuff as i can. The job is in the design department.

    • Thanks for your comment. It’s difficult to say exactly what you need to know to be an engineer in the Process Systems and Solutions organization. You might be a hardware design engineer where Kirchoff laws, thermodynamics, power & grounding, etc. are all important. Or, you might be a project engineer working at customer sites where process knowledge through chemical engineering and process control courses are good to have as background. Or you might be a business development engineer where broad knowledge of automation, marketing, and people skills is important. By and large being an engineer requires one to be a problem solver, so any classes that exercise analytical thinking will help to prepare you for whatever your role and career path might be. Sorry I can’t get any more specific than that.

      • how about that? says:

         thank you Jim for your reply. It cleared the air regarding my problem. Well, i think that i will be in the hardware design department. As i understood the engineers in RO from PSS had to do everything by themselves, design, promote the product, etc, and because it was overwhelming they decided to make a new department for design. Now i don’t know for sure if it’s hardware, but i was told that i will be working as an automation engineer. Therefore i could only assume that hardware is the domain. So Khirchoff, power and grounding and thermodynamics it is. Anything else?:) Thank you!

        • An automation engineer should have a good understanding of the process being controlled, the control system and its capabilities, instrumentation, and the applicable standards. You won’t learn all this in school, but will have the opportunity for ongoing education throughout your career.

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