#WishIknew How does radar level measurement work?


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I wish I knew how does radar level measurement work!

We have a bunch of articles at Visaya talking about radar and similar principles. I’ll list some of them at the end. First, you have two kinds of radar level transmitters, free space and guided wave. Free space radars never make contact with the product, but if you have high turbulence or low dielectric constant (DC), then you might want to go with a guided wave radar. It has a probe in constant contact with the product to guide the waves created by the transmitter.

how does radar level measurement work
Courtesy of Smar

Both types work with the same principle, time of flight or ToF. The devices generate electromagnetic waves that travel from the device to the product and return. The product needs to have a minimum DC to reflect the signal. Then the radar can calculate the level, because the time of emission and return is proportional to the distance.

Everything inside the tank that conducts energy, such as level switches or heater systems, can reflect the signal. If the product has a low dielectric level, then the radar may find a false level. You may also wind up with bad readings from vapor, foam, or other product conditions.

You can find many solutions to avoid this issue – high-frequency devices, echo analysis, stilling wells, and more. Then the transmitter can provide good accuracy and reliable measurements.

This list has articles with more about radar level measurement:

Non-contact radar level transmitters and their frequency bands! Hey, all right? Today we’re learning more about non-contact radar level transmitters, also known as free space radars. Yep, same device, just a different name. And you’ll find that they have various frequency options as well. Which should you choose? Let’s learn a little more!

Guided wave radar and you! – Here we are again to chat some more about radar! Today, the star of the article is the guided wave radar. Do you know when you should apply a guided wave radar rather than a non-contact radar? If you don’t, then keep reading! If you do, then keep reading anyway. You might see something new or find something to argue about with me.

The definitive guide to time of flight (ToF) devices – Here we go again with another guide! If you haven’t read our definitive guide to pressure transmitters, then definitely check it out. This topic actually relates to what you learned in our previous guide. Time of flight (ToF) devices measure level, just like differential pressure (DP) transmitters. Of course, they do it in a different way, meaning new pros and cons.