What is the percentage of new installations that use fieldbus over 4-20, 3-15, etc.? What industries are changing out 4-20mA for newer digital technology? Is any industry using fieldbus for applications other than monitoring? Does anyone have a current graph, chart, or information about industries using process control signals worldwide? Who is using what control signals, and why?

Thank you.

 

We have been using Foundation fieldbus since 2000 - over seven years. We have been using it for control, and doing control in field devices, for the entire time.

Try going here http://wwww.fieldbus.org

ISA just did a survey through INTECH magazine, http://www.isa.org/InTechTemplate.cfm?Section=Article_Index1&template=/C ontentManagement/ContentDisplay.cfm&ContentID=60680

(be sure to get the whole link - there's a link on the ISA home page at http://www.isa.org ).

There are graphs here, but I believe they are based on reader responses to a survey from earlier this year.

To my knowledge, Shell, BP, Saudi Aramco, and Chevron are all standardizing on Foundation fieldbus for new installations, or retrofits / upgrades of existing plants that are primarily pneumatic. A lot of their plants already have a large installed base of smart instruments which are wired point-to-point (no network or bus) and use a proprietary digital protocol (Honeywell DE, Foxcomm, etc.) or use a HART signal superimposed on the analog 4-20 to get a degree of digital integration.

Not sure what you mean by using control signals. I think about everyone here does that.

John Rezabek
ISP Lima LLC