Capacitance Level Transmitter

For continuous level measurement capacitance principle can be used, where a capacitance is formed between the sensing probe and the vessel wall. A high frequency sine wave is applied between the probe and the vessel wall. As the medium level change, it introduces a change in current of the applied sine wave. When the capacitance in the vessel increase, impedance will decrease and current will increase. Vice versa, when the capacitance in the vessel is small, impedance will increase and current will decrease.