Fieldbus / Analyzers

Reader feedback: March 2019

Readers respond to February's On the Bus, and January's Develop Your Potential columns

I enjoyed reading John Rezabek’s article, “Grandpappy of device diagnostics.” I definitely had some flashbacks while reading. I did a gas chromatograph (GC) interface to Provox at an ethylene plant. The GCs sampled multiple streams in the plant. We had a binary coded decimal (BCD) interface between the GC and the DCS that told you which stream was being sampled, that it was a good sample (at least the GC thought so), etc. Lots of code on the DCS to store all of the signals, hold last signal until you had a valid update, etc.
It worked great except when it didn’t. Once it a while, it would drop a bit and get things out of sync. You also learned with the BCD signal that you better tell the DCS what to do with the BCDs that didn’t mean something (bogus bits). Anyway, we had a party when they finally got some new GCs with a real Modbus interface, so we could throw all of that code away.
The good ole days—no thanks. I hug my DeltaV every morning.

Calvin Burnett
Technical manager, Experitec

Russ Rhinehart’s “The elephant in the room” was an excellent article about the gap between academic engineering and engineering practice. I transitioned from advanced process control to process safety several years ago. We're seeing this very same problem everywhere—it’s not limited to Laplace transforms and Bode diagrams.

I'm leading a program at AIChE to address this gap in the field of process safety. For the past few years, we've conducted faculty workshops at various operating facilities across the U.S. These workshops are sponsored and hosted by various industry members of CCPS and are free to attending ChE educators. The desired outcome from these workshops is that the attending faculty are equipped to teach process safety—both as a stand-alone topic as well as embedding it in other courses such as design, unit ops lab, thermo, transport phenomena and so on. There are not many ‘Eureka moments,’ but we are making progress

Anil Gokhale, P.E.
Director, CCPS Projects, AIChE

Anil, I greatly appreciate the feedback, and certainly support your efforts. I'm very glad that a person from an industrial background is leading the initiatives. I've participated in several in the past, led by academics—they don't even understand the industrial message.

We need change, but I think the environment needs substantial change before academe will change. The environment includes funding sources, federal regulations, state regulations, academic self-governance, scientific journal review procedures, academic recognition awards,etc.

Back in 1988 or so, as a new faculty member, I was at one of the three-day workshops at Dow in Midland. It was great. Keep on. Add value. As you indicate, the gap is in all aspects, but especially so in the safety culture and experience of research-oriented faculty members.

R. Russell Rhinehart

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