At this time of parties and feasts with family and friends, it's interesting to reflect on the feasts we celebrate with our "work" family. In the large process industries, we deal with equipment full of hot, flammable, explosive, toxic substances—in the words of OSHA, "highly hazardous." We celebrate making it through a year or two or five while managing to protect our employees and contractors from harm.
What do our vendors celebrate? Well, we know it typically isn't the smashing success of fieldbus. Fieldbus sales lag behind good ol' 4-20 mA analog by almost 10 to 1, by some accounts. Big new projects that could save millions in copper by deploying Foundation fieldbus or Profibus contentedly nurse at the warm and familiar breast of analog solutions. When fieldbus shows up at the junior high lunch, it's often shunned from the "popular table" like the debate club captain. This apparent lack of popularity has some vendors, especially those who measure success by volume and market share, declaring that fieldbus is a disappointment, if not a failure. They point to end users who say, "Fieldbus is too hard, we love HART," while admitting that few really use HART for much beyond range changes and initial configuration. This underutilization masks issues with HART that mirror the challenges of fieldbus. Those of us who use both will tell you, HART is no easier when you try to use it as a fieldbus.