Manufacturing AUTOMATION

ONE ON ONE: Interview with Dick Caro

August 18, 2011
By Perry Marshall

Dick Caro led the charge for adopting Ethernet as a fieldbus and a means of achieving interoperability between hundreds of products. He held positions at Foxboro and ARC Advisory Group, and has authored books and papers. He has also served as chairman of the Fieldbus Standards Committee, and was elected to the Automation Hall of Fame. The following is an excerpt from Manufacturing AUTOMATION contributor Perry Marshall’s interview with Caro:

Perry Marshall: How did Foundation Fieldbus High-Speed Ethernet get started?

DICK CARO: I joined ARC Advisory Group in 1997 and I became Andy Chatha’s network guy. Then I got an opportunity to make a presentation at the ARC conference. I presented a milestone paper in which I tackled the myths around Ethernet. I [debunked] every myth surrounding Ethernet, such as “;it’s nondeterministic and inefficient”; and that the link is too limited. I tore those myths down by detailing the use of active switches, the reliability of active switches, what they did for the network, and the benefits of full-duplex switched Ethernet in creating a completely deterministic Ethernet. As I walked to the back of the room after the presentation, John Pittman, Steve Glanzer and the technical steering committee for the Fieldbus Foundation waved me over and said, “;Can we do Ethernet instead of H2 for fieldbus?”; I said, “;Absolutely. You just have to do a good job of it and make sure that it can’t be subverted in its implementation.”; That was in February and by the end of April, the entire project had been funded. That’s how Foundation Fieldbus High-Speed Ethernet (HSE) got started.

P.M.: How did the fieldbus wars start?


D.C.: The work at ISA was complete, but there were fights at IEC. I took over both the ISA SP50 committee and the IEC Working Group Six chairmanships. The committee’s work was being voted down by too many nations. It wasn’t being approved due to an organized campaign by Profibus. The Profibus Group gave us all the technical reasons why they were voting against it. We countered everyone by making changes in the standard, but they still voted against it. We had a lot of difficulty figuring this out.

The ultimate challenge came at the IEC meeting in 1998. The delegate from Germany got up and moved that we adjourn. I ruled him out of order. Eventually, they withdrew from the meeting. Their leaving gave me an opportunity to sit with the delegates from the U.S., England, France, Italy and Canada. We actually went through and wrote opinions on each of the negative votes, invalidating the technical reasons that the dissenting National Committees had given. That weekend, I reviewed the notes and put together a response. When the IEC meeting convened, they asked for a report from each of the standards committee chairmen. I submitted a report in which I systematically argued against each of the international votes, and submitted a motion that we invalidate the negative votes.

In the months before the final vote, I was with ARC at Interkama in Düsseldorf. My boss and I were called to a meeting at the booth of a large automation company. The company asked us to make sure the current vote before the IEC passed because that was the position the company would take. Wanting to keep my job, I agreed. I later resigned as the convener of Working Group Six because I couldn’t be involved in the ongoing support of something that I didn’t believe in.

P.M.: How did you feel about the thorny situation?

D.C.: Fieldbus was not the issue. The issue was international standardization. Before the fieldbus wars, international standardization was just like standardization in the U.S. It meant the standard was done for the benefit of the user. The user saw a commonality amongst his suppliers. We took votes all along the way in fieldbus. Do we want to have a multi-standard, or do we want to have a single standard? Every time, the vote came out strongly for a single standard. Euro Standards have a different mission. The mission for a Euro Standard has nothing to do with the use of the standard or the end-user. It’s to make sure that governments do not impose laws or local standards, which restrict international commerce between the nations. The European-based companies’ goal was to change the mission of the IEC to match the European commonwealth standards mission. That is, to decrease barriers of trade between nations. It had nothing to do with developing a single standard for the end-user. Because of that, the Europeans felt the need to build multi-standards. Once a multi-standard is approved, then you can sell products based upon it in any country in the European commonwealth.

A longer version of this interview is available at Perry Marshall is an author, speaker and consultant in Chicago, Ill. Contact him through the editor of this publication by e-mailing To contact Dick Caro, e-mail

Print this page


Story continue below