Capacitive measurement principle

The principle of capacitive displacement measurement using the capaNCDT (capacitive Non-Contact Displacement Transducer) system is based on how an ideal plate-type capacitor operates. The two plate electrodes are represented by the Sensor and the opposing Measurement object . If a constant alternating current flows through the Sensor capacitor, the amplitude of the alternating voltage on the Sensor is proportional to the distance between the capacitor electrodes.