Water Level Measurement Using Capacitive Sensor

Level the capacitance of the level electrode is proportional to the liquid height hw.

Water level measurement using capacitive sensor.

Capacitive sensor for water level detection has been fabricated. Liquid level sensing is based on the theory of a ratiometric measurement using three sensors as shown in figure 2. It has typically high impedance sensor particularly at low frequencies as clear from the impedance reactance expression for a capacitor. With a capacitive sensing based solu tion no moving parts or sensors need to be in direct contact with the liquid to be measured.

Performing system calibration using labview software can help achieve higher accuracy. When the tube starts to fill more and more of the space will be occupied by water. 5 v pp3. This sensor comprises a printed circuit board pcb with configuration of two interpenetrating comb electrodes.

A water level measurement using an interdigital capacitive sensor with low cost low energy good repeatability high linearity and ease of installation is proposed with a support of experimental results. The space between the tubes is the dielectric. Also capacitive sensor is a noncontacting device in the common usage. ε r eff 1 ε r 2.

There are two types of capacitive level sensor contact type or non contact type for water level measurement. When the tube is empty the space is occupied by air. From this equation the measured capacitive is proportional to the length submerged into water as the approximate capacitance per length of track for a coplanar sensor remains constant. 1 have described the design and implementation of a liquid level measurement system based on a remote grounded capacitive sensor.

A rod of stainless steel and a polytetrafluoroethylene ptfe insulated wire have been used for electrode of capacitive sensor. For d h 1. In this research water level sensor based on capacitive principal created using two copper plates with height h width b and distance l between two plates respectively 0 040 m 0 015 m. It has to be as high as the maximum max allowed liquid level.

Instead the liquid level is measured with a non contact capacitive sensor deployed externally to the reservoir.