The flow measurement instruments are very important devices in industrial processes, as they allow controlling and monitoring the flow of liquids or gases. In this article, we will talk about two commonly used types of flow instruments: electromagnetic flowmeters and rotameters.

What is an electromagnetic flowmeter?

An electromagnetic flowmeter is a device that is based on Faraday’s law to measure the flow of conductive liquids, such as water or saline solutions. It consists of a tube through which the liquid flows, and two electrodes placed perpendicular to the flow of the liquid. When a magnetic field is applied, an electromotive force is generated that is proportional to the velocity of the liquid and, therefore, the flow rate.

What is a rotameter?

A rotameter is a flow measurement device that is based on the measurement of pressure drop in a tube. It consists of a vertical tube through which the liquid or gas flows, and a ball or float that moves up or down in the tube depending on the flow rate. The position of the float corresponds to the flow rate, and can be read on a graduated scale on the tube.


Can electromagnetic flowmeters measure non-conductive liquids? No, it should be noted that electromagnetic flowmeters are only suitable for conductive liquids, which limits their applicability in certain cases.
Are electromagnetic flowmeters more accurate than rotameters? Yes, electromagnetic flowmeters are generally more accurate than rotameters.
What types of liquids and gases can be measured with rotameters? Regarding the measurement of liquids and gases, rotameters are suitable for most of them, including those that contain suspended particles, highlighting their versatility in various applications.

In summary, the choice between an electromagnetic flowmeter and a rotameter will depend on the type of fluid to be measured, the required accuracy, and the cost of the instrument. Both are reliable and accurate devices that allow controlling the flow of liquids and gases in industrial processes.