Ultrasonic Vs. Magnetic Meters: Which Works Best For Low-Flow Applications?

Flow meters are an important component in water treatment systems. Operators rely on the accuracy of a flow meter’s readings, particularly for chemical dosing and other low-flow processes. Accuracy in metering depends on a range of factors, from the types and quality of liquid being metered to the meters themselves. Generally, the two most accurate meter technologies are static meters (i.e., those without moving parts), which includes ultrasonic and magnetic flow meters (mag meters).

Ultrasonic meters detect and measure flow using sound waves, and Ultrasonic meters work in one of two ways. Doppler ultrasonic meters send out a signal and measure the change in frequency as it bounces, while transit-time ultrasonic meters send one signal upstream and one downstream and measure the difference between them. Meanwhile, mag meters create a magnetic field and measure the voltage of any conductive material passing through the field.

Each type has its advantages, but the right fit will depend on the application.