What is the reason for the large error of electromagnetic flowmeter?

Case introduction

There may be many reasons for the large error of the electromagnetic flowmeter, which mainly include the following aspects:

The influence of the measured medium. If the measured medium contains bubbles, or the measurement is performed when the tube is not full, it will cause deviations in the measurement results. In addition, if the conductivity of the measured medium changes drastically, it will also cause large fluctuations in the measured value.

Improper selection. If the flow rate range and conductivity requirements of the electromagnetic flowmeter are inconsistent with the actual working conditions, it will also lead to measurement errors. In addition, if the selection of electrodes and lining materials does not match the characteristics of the liquid being measured, measurement errors will also occur.

Installation problems. If the installation location of the electromagnetic flowmeter is improperly selected, such as installing it in an environment with electromagnetic interference, or the sensor is installed in an incorrect location, the measurement accuracy may be affected.

Other interference effects. Space electromagnetic interference, connecting cable problems, grounding problems, etc. will all affect the measurement results of the electromagnetic flowmeter.

Problems with sensors and excitation coils. If the sensor and excitation coil are installed asymmetrically, or the excitation stability is poor, measurement accuracy will also be affected.

For these possible reasons, corresponding measures can be taken to reduce the measurement error of the electromagnetic flowmeter, such as installing gas collection bags and exhaust valves to eliminate gas in the pipeline, selecting appropriate electrodes and lining materials, Avoid installation in environments with strong electromagnetic interference, ensure correct cable connections and maintain good grounding, etc.