Answer / carl_ellis

There are thermal dispersion, coriolis, differential pressure multivariable and solids belt scale mass flowmeters from a variety of manufacturers.

Each device has a specific procedure for trimming the mA output, if that's what the output is (it could be digital or fieldbus protocol). The specific manufacturer provides instructions on trimming the mA output.

The decision is to whether one trims the output to a calibrated milliammeter or whether one does a 'loop calibration' in which the HMI value is trimmed to match the flow meter's output.

A positive means of flow shutoff, bubble tight valving, is necessary because thermal or pressure siphon flows as well as back flow leakage through a pump or 'leaky' valves can occur when the pump is turned off.

Carl Ellis
Measure First

Answer / senthil

carl ellis,

How to calculate the flow rate in Vortex flow meter?What is K factor?Can you give me an example calculation to understand the same as better?

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