Calibration of DP Flow

What has Rosemount had to say on the topic?

Somewhere there's a "sizing sheet" for the orifice plate, which states the maximum flow rate at a calculated DP for that specific orifice plate. The engineering units for flow rate and DP are stated, as well.

Find the sizing sheet and get the calculated DP value, the max flow rate value & the engineering units from it.

Then use a HART communicator (351 or Meriam 4051 handhelds) to set the correct

engineering units
LRV = 0
URV = value from design sheet

on the transmitter.

If you enable the square root, the transmitter's output will be linear will volumetric flow rate.

Multivariable transmitters will calculate inferred mass flow when supplied with an external temperature measurement, but a DP transmitter can only infer volumetric flow from DP, not mass flow.

You can fake a mass measurement by assuming densities at a fixed temperature and pressure and then ranging the 4-20ma volumetric flow signal in your receiver device appropriately.

The formula for mass flow is probably on the forum and definitely on the web, but you don't need it if you're faking it by just ranging the volumetric flow in mass units.

The sizing sheet below is for a multivariable, so the engineering units are mass units, but the concept is identical for volumetric flow sizing.

This orifice plate above was designed to produce 7.00"w.c. DP at a mass flow rate of 3.30 Kg/Min.

Thanks Very much Mr. Carl