#WishIknew How does capacitance level measurement work?


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I wish I knew how does capacitance level measurement work!

You can use capacitance level devices for level measurement and point level detection. Capacitance basically means the ability to hold a charge, right? Here, your device measures level by detecting the change in the capacitance of the capacitor created by a sensor probe and a conductive tank wall.

When you have air between the sensor and the wall, you have a set value of capacitance. As soon as the level rises in the tank, the capacitance rises too. Make sense?

You can use these devices in nonconductive media with conductive values below one micro-siemens per centimeter. You’ll need a local calibration, though. For processes in products with values higher than 100 micro-siemens, the factory can do the calibration for you! But remember, there’s a gray area between these values where you shouldn’t use these devices.

One type of sensor can use this technology in plastic tanks. Also keep in mind you need the right ground for the tank and sensor. Your vendors should tell you what you need in your process.

This video will tell you more about capacitance level measurement: