A capacitive level sensor is a sensor that measures the level height by measuring the capacitance change between the liquid and the electrode. The principle is based on the definition of the capacitance, that is, the permittivity between the two conductors is related to the shape, size, and position of the constituent conductor. In a capacitive liquid level sensor, the liquid forms a capacitor on the electrode, from which the height of the liquid can be measured. Specifically, when there is no liquid in the capacitor, the capacitance approaches to zero. When the liquid increases between the electrodes, the electrical capacity also increases accordingly. This is because the presence of the liquid on the electrode increases the distance between the two conductors, increasing the dielectric constant, thus increasing the capacitor capacity.
