Instead the liquid level is measured with a non contact capacitive sensor deployed externally to the reservoir.
Water level measurement using capacitive sensor.
Liquid level sensing is based on the theory of a ratiometric measurement using three sensors as shown in figure 2.
A rod of stainless steel and a polytetrafluoroethylene ptfe insulated wire have been used for electrode of capacitive sensor.
It has to be as high as the maximum max allowed liquid level.
2 2 liquid level capacitive sensing 16 2 2 1 liquid level coplanar plate capacitive sensors 16 2 2 2 differential and ratiometric measurement of liquid level 19 2 2 3 active shielding 21 2 2 4 out of phase liquid level technique 23 2 3 fdc1004 capacitance to digital conversion 25 2 4 i2c data transfer between mcu and fdc1004 26.
The space between the tubes is the dielectric.
It has typically high impedance sensor particularly at low frequencies as clear from the impedance reactance expression for a capacitor.
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.
When the tube starts to fill more and more of the space will be occupied by water.
1 have described the design and implementation of a liquid level measurement system based on a remote grounded 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 and 0 010 m.
ε r eff 1 ε r 2.
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.
This sensor comprises a printed circuit board pcb with configuration of two interpenetrating comb electrodes.
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.
Also capacitive sensor is a noncontacting device in the common usage.
There are two types of capacitive level sensor contact type or non contact type for water level measurement.
Performing system calibration using labview software can help achieve higher accuracy.
With a capacitive sensing based solu tion no moving parts or sensors need to be in direct contact with the liquid to be measured.
5 v pp3.