One of the primary and most often used bus communication protocols deployed in plant and process operations is Modbus. This open architecture, master-slave/client-server communication has been a de facto standard since Modicon’s initial release in 1979. According to the Modbus organization, there are more than 7 million Modbus nodes operating in North America and Europe alone.
 
Getting flow measurements over Modbus has always presented extra considerations because of the vast options for flow rate engineering units, totalized flow (and to allow resetting or not), and their resolutions.  

With the recent addition of the Modbus option to the ST51A and ST75A product family, FCI offers more Modbus compatible thermal mass gas flow meters than any other manufacturer.  Whether your application is in machine control, plant air flow, pilot plant development, process gas flow control or off-gas reporting, within pipe diameters from 1/4 inch [6 mm] to the largest of stacks or ducts, FCI now has flow meter with Modbus I/O solution. The Modbus options are the wired-type, RS485 per EIA/TIA-485, as RTU or ASCII.  They support both MS and LS 16-bit type as well as 32-bit Daniels extension type.

FCI Models With Modbus 
ST51A Mass Flow Meters
ST75A Series Mass Flow Meter
ST80 Series Mass Flow Meter
ST100 Series Mass Flow Meters
MT100 Series Mass Flow Meters