To standardize or not

About three decades ago, the newly minted Fieldbus Foundation adopted the byline, “The freedom to choose, the power to integrate”. Somehow, I’m inclined to believe—and this is purely conjecture on my part—the “freedom to choose” had much to do with the DCS and field device proprietary integration of the contemporary Honeywell TDC-3000 and Honeywell “DE” field devices.

It was a novel feature that extended the Honeywell footprint and denied competitors from sharing in the projects replacing legacy pneumatic and 10-50 mA-based control systems. The downside, in addition to being a closed proprietary protocol that required the end user to use strictly Honeywell transmitters, was that no one’s favorite valve positioner (among other things) could be digitally integrated with TDC-3000 like “DE” transmitters. Positioner “intelligence” was potentially much more interesting, as end users were already attempting to utilize advanced diagnostic tools to determine which valves warranted a rebuild or replacement during infrequent turnarounds.

We also learned from the leadership of Fisher-Rosemount of the 1980s/90s that the Honeywell DE innovation was a monumental concern. It spurred the invention of HART for digital communication with field devices, and HART was immediately released as an open protocol, which any instrument manufacturer could adopt. In a sense the seeds of “freedom to choose” were already being sown. 

Meanwhile, I recall our plant’s highly respected controls leader questioning whether intelligent field devices were even worth the premium. In the late ’80s, the utility of a “smart” transmitter was often finished once the range was configured. There were some interesting variables beyond the primary process variable, like transmitter case temperatures, but no control systems at the time could access them or display the other variables of interest. Turn a few trim pots and you don’t need a handheld or additional training to get a measurement into the system. We already had the freedom to choose when everything was analog, including controllers (i.e. electronic and/or pneumatic). We could deploy an entire ISA exhibit in a process plant if we were so inclined (and unleashed). 

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A useful lesson for budding I&C specifiers was to engage with the plant’s maintenance staff or instrument shop. The technicians—even their supervisors—didn’t necessarily have visions or ambitions for how great the latest technology might be. With some exceptions, most technicians are happy if you don’t saddle them with odd ball instruments or other technology that are different than the installed base. This came painfully to light when a transfer from the North Slope swept in and installed his favorite D/P, pressure and temperature instruments. They were an early version of the vendor’s HART-capable instruments requiring a handheld communicator to configure. Problem was, refinery debottlenecking—even a decade after the plant was online—often meant what was originally a 0-100-inch D/P flow application needed to switch to 0-200 inches, which for the HART devices required a capsule change. They also were generally grumpy about being left out of the loop when the selection was made.

This less-than-magical, arguably obvious insight into the successful (or not) introduction of “change” to process plant equipment means the engineer must become a salesperson for the things he or she wants to try, assuming they already have the endorsement of the end user (e.g., operations). I like to say we’re a link in the chain of delivering process insights to the end user, and maintenance ensures the final link delivers the desired measurement reliably. If they’re not bought in, your new device may end up abandoned or in the dumpster.

It can be tough to cultivate a steady rapport with shop technicians and supervision; often, a union environment starts out with resistance and distrust for management, which includes the entry-level engineer. Our ardent vendors are a link as well, and they know the path to getting their new offering a trial in your facility can be a struggle. So, when the friendly salesperson has sold you on a technology that deviates from the norm, have them visit your victims in the shop as well to help you win them over.  

Sometimes “Mossy Oak” ball caps and breakfast pizza can be surprisingly persuasive.