Design and Testing of a Capacitive Sensor for Liquid Level Measurements

Capacitive liquid level sensors are attractive for applications requiring long-term reliability and resistance to corrosion, such as in environmental experiments or domestic water monitoring systems. While the basic operating principles of these sensors are well understood and thoroughly explored in existing literature, this paper aims to validate a specific implementation involving insulated parallel plate electrodes. During experimentation, a consistent discrepancy was observed between calculated and measured capacitance values, with measured values nearly double those predicted by a simple series dielectric model. Rather than pursuing a full theoretical treatment of the discrepancy, the authors present empirical correction factors supported by measurement data. A brief discussion of relevant literature on layered dielectric behavior is included to provide context. The results are intended to support others working with similar sensor geometries and dielectric interfaces by offering practical guidance and calibrated expectations.