Electromagnetic Flow Meter

What is Electromagnetic Flow Meter?

Electromagnetic Flow Meter is a device to measure the flow rate in a pipeline by utilizing Faraday’s Law of  electromagnetic induction. It is often used in water/ waster water industry, chilled water cooling systems, food and beverage, chemical, pulp and paper industry, etc. There are different types of electromagnetic flow meter, including in-line type (intrusive), insertion type (non-intrusive), battery-powered type (suitable for remote area), and etc. 

 

Working Principles

The measuring principle of the electromagnetic flow meter (magmeter) is based upon the Faraday’s Law of electromagnetic induction; whereby a voltage is induced by an electrical conductor passing through a magnetic field.

In the flow meter, the medium acts as the electrical conductor when flowing through the meter tube, the induced voltage is proportional to the average flow velocity (the faster the flow rate, the higher the voltage).

The induced voltage is picked up by a pair of electrodes (mounted in the meter tube) and transmitted to a flow transmitter to produce various standardized output signals. Using the pipe cross-sectional area, the volumetric flow rate is calculated by the transmitter.

The following equation is applicable to the induced voltage: U = kBVD where