Capacitance Level Switches

The principle of detection involved is the Capacitance phenomenon, which is developed between the probe and
the reference. The amount of capacitance developed in any vessel is determined by the size (surface area) of
the probe, the distance from the probe to its ground reference, and the dielectric constant of the medium being
measured. The amount of capacitance developed in a vessel becomes dependent upon the amount of the probe,
which is covered with media. As the media rises and falls in the tank, the amount of capacitance developed
between the probe and the ground reference also rises and falls. This change in capacitance is detected by
employing Radio Frequency (RF) and converted to a digital waveform proportional to the change in level which in
turn is used for level detection and monitoring.