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Users driving the bus

April 5, 2007
Contributing Editor John Rezabek provides commentary on end-user participation in councils and committees, formulating directions and priorities as a valuable service to the supplier community.
By John Rezabek, Contributing Editor

One unique aspect of Foundation fieldbus (FF) is the degree of user input. FF is distinctive in the voice it gives its user advisory committee, the regional end-user councils, and global End-User Advisory Council (EUAC). Our input to the Fieldbus Foundation’s executives and board of directors provides a direct line to the leaders guiding the major automation suppliers. By expressing the needs and priorities of our user community, we’re guiding the progress of an entire automation infrastructure, not just one supplier’s product.

Users participating in end-user councils and formulating directions and priorities are providing a valuable service for the supplier community as well. While it may have been a safe bet that satisfying the priorities of a major oil and gas player would mean strong sales with its customer’s peers, today’s path to market preeminence is no longer so straightforward. Systems don’t stop at the I/O boards, and instruments don’t exist in isolation. Some suppliers can offer a degree of “one-stop shopping,” but never before has “playing well with others” figured so prominently in a supplier’s resume.

Over the past several years, the foundation’s EUAC has presented the supplier community with a “top 10 list” of features, capabilities, concerns and conflicts selected as most urgent to make progress on or resolve.

Fieldbus integration with Safety Integrity Level-rated (SIL) systems has been first or second on that list for two years, and work on it has record participation from both end users and suppliers. Foundation fieldbus already has concept approval for SILs from TUV, and both lab and “live” demonstration projects are planned for next year. Among the end users hosting beta tests or demonstrations are Saudi Aramco, Shell, BP and Chevron. Products the rest of us can start specifying for projects are anticipated by the end of next year.

Thousands of sites are using Foundation fieldbus, and many have noticed that the wealth of new information and diagnostics is a challenge to mine or manage. These concerns made the “top 10,” and now a new feature is ready for implementation in future devices (and/or flash upgrades of existing devices when supported). The feature conforms to the existing NAMUR standard NE107, and gives users a standard way to choose which diagnostic alerts to enable, and where to route them. For example, “critical” alerts can be sent to operators in real time, while advisory alerts go to maintenance for action during normal business hours. At our site, we might route a valve positioner’s “low-low instrument air supply” alert to the operator on shift (who knows the consequences and can take meaningful action), while sending an “excessive valve reversals” alert to the maintenance and systems guys. (Maintenance can order new packing and the systems guy can fix the controller tuning.)

Many devices already support this feature. Thanks to the work of the technology experts at the Fieldbus Foundation and its members, it will soon become a standard offering.

Making its first appearance in the “top 10” as an expression of concern to the supplier community is the subject of “HART versus Foundation fieldbus.” Newer HART I/O promises support for FF-like diagnostics, but some end users feel they’re getting a smokescreen when they ask suppliers to clarify the real capabilities and limitations. DCS vendors, eager to win upgrade jobs in brownfield sites, should be telling their customers how much of the installed base of HART devices will need upgrades to support the watered-down, fieldbus-like diagnostics.

If I have to buy new I/O cards and new devices, why not take the opportunity to convert to fieldbus? Many of us still struggle with fieldbus-unfriendly legacy systems and have little choice but to keep using HART or proprietary digital integration. However we don’t think this should be touted as a “preference,” any more than those of us in northern latitudes should be seen as preferring freezing rain to a sunny day at the beach. We want our supplier community’s best minds and talent working on the most promising technology of the day, not putting a new paint job on a vintage vehicle from 1980.

End users looking for a way to participate in their region’s end-user council should post a message to that effect in the “FUN” forum . It’s free, and there’s also a lot of help there and good advice from suppliers and end users around the world.

Fieldbus Smokescreen? Helson Responds

By Ron Helson, Executive Director, HART Communication Foundation

In the above article by John Rezabek, “Users Driving the Bus”, John’s allegiance to Foundation Fieldbus is obvious, and that may be clouding his ability to properly represent the diagnostics capability of HART devices.

I’m not sure why “HART vs. Foundation Fieldbus” made the FF EUAC “Top 10” list, but I suppose it could be because users are starting to understand that the communications protocol is less and less a factor in the diagnostics capability of intelligent devices.

The term “FF-like diagnostics” as used by John is very interesting, since many of the initial and current FF registered devices are natively HART devices with an additional communication board to translate the data from HART to FF format. Consequently, the diagnostics in these devices is virtually identical.

The statement about “watered-down, fieldbus-like diagnostics” is also very ironic and misleading. Contrary to the implication, the fact is that all HART-enabled devices—dating back to the early 90s—contain device status and diagnostic information that is easily used by today’s HART-enabled automation and I/O systems without any upgrade to the device.

Users evaluating their automation system and field communication protocol options must consider many issues including, device replacement, training, project risk, infrastructure upgrades, automation and I/O system upgrades and others. In many cases, total cost vs. benefits have shown HART to be the most cost-effective option.

Users have a responsibility to their management to evaluate all their options for upgrading automation systems on brownfield sites including using the HART-enabled field devices that are currently installed. John’s implication that HART is not the most “promising technology of the day” is, we believe, incorrect.

Here are a few facts to set the record straight:

  1. The real issue is taking advantage of the intelligence and diagnostic information available in smart field devices and using that information to keep plants competitive—not the protocol that is used to connect the device to the control system.
  2. Very few, if any of the HART-enabled devices installed in user plants would require upgrade for their information to be integrated into control or asset management systems. The guiding principle for HART Communication Foundation is that all enhancements to the HART technology be backward compatible.
  3. If users feel that they are getting a “smokescreen” when they ask suppliers to clarify the real capabilities and limitations of their proposed solution, they should consider another supplier or call the HART Communication Foundation for clarification.
  4. Suppliers must provide several technology solutions because it’s to their advantage to be protocol independent in offering the best solution for their customers application. If HART happens to be the logical choice, that hardly qualifies as a “smokescreen.”

If you want to learn more about HART technology, the HART Communication Foundation can provide you with the facts to disperse the “smokescreen."

About the Author

John Rezabek | Contributing Editor

John Rezabek is a contributing editor to Control

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