Is the accuracy of a mass flow meter affected by temperature interference?
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I have an Emerson mass flow meter with a range of 80 tons per hour. During use, it was found that the accuracy of measuring the material being transported varies depending on the temperature of the medium being transported; for example, when the medium temperature is 40 degrees, the actual value is higher than the measured value. At 60 degrees, the actual value will be lower than the measured value. It was sent to Emerson’s service center for verification three times, and no issues were found, but in actual use the error does vary significantly with temperature. I’m also confused these days – how could such a strange thing happen to a flow meter worth 120,000? Also, I’m not sure whether the amount of the medium being transported will affect the accuracy of the flow meter For example, is the precision of transporting 300 tons at once higher than that of transporting 200 tons at once?
The Emerson mass flow meter is equipped with temperature compensation; the 9-core cable includes 2 main excitation coils, 2 left excitation coils, 2 right excitation coils, and 3 thermistor wires for temperature measurement
It is necessary to take into account the impact of temperature on density and adjust the parameters of the flow meter accordingly.
I don’t know what material you are transporting; it’s possible that changes in temperature cause variations in the density of the material, which in turn results in inaccurate measured mass flow rates
It shouldn’t be the temperature that affects density, because the principle behind the rapid flow rate in your device is vibration-based. Density is finally calculated from mass! I quite agree with the opinion from the second floor
Does the density of the material change significantly with temperature? If the changes in the flow meter are consistent, then there is nothing unusual about it. In chemical production, the error of the ammonia flow meter due to temperature changes is constantly changing.
Generally, mass flowmeters have temperature compensation for measurement. The phenomena you listed seem to be issues with the flow meter’s settings. Check the settings to see whether the signal is output in terms of volumetric flow rate or mass flow rate. Some flowmeters convert density to a volumetric value that is then sent to the DCS, where it is converted back to a mass value; this can result in temperature errors. Please check the settings carefully!