The capacitance level sensor offers a way to sense liquid level when other methods won’t work. For liquids that coat, or foul, plate onto float switches the capacitive sensors are immune to this failure.
They can sense through large amounts of buildup from scale or simply viscous liquids like honey that leave large amounts of material clinging to the pipe.
FOULING LIQUIDS
Capacitance sensors can sense nearly any substance, (link to chart of material capacitance values) even solids, without fouling. Sticky, scaling, coating, crystallizing, and viscous liquids are no problem. The only problem was how to position them so they can be in position to sense the liquid! This is usually not easy because the surface of the sensor may not be suitable for corrosive chemicals. One solution is to mount the sensor outside a tank and have it sense through the tank wall. (as long as the tank wall is not metal, and it is less than 1/2″ thick) To do this, it requires fastening a bracket onto the outside of a tank wall. Our unique pipe-mount capacitance sensor means that installation is now easy as it can be mounted through the top of the tank. We have many solutions for this on our tank alarm page.
The innovative feature that allows the capacitance sensor to work is that the sensor is located inside the pipe. That way the sensor is protected from the chemicals, and so it can work in extremely challenging liquids that coat or crystallize and give other types of sensors problems.
MATERIALS
The only wetted parts are the pipe material, (polypropylene or PVDF) The resulting sensor is easy to clean because the surfaces are very smooth. There are no moving parts.
Finally, this extended range capacitance sensor can be used with any of our level products like our tank alarms and level controllers.