Abstract
Abstract
This paper uses the co-planar interdigital electrode (IDE)
sensor to measure water level. The researchers generally
characterize the interdigital electrode sensor as a fringe field
capacitor sensor developed on the printed circuit board and utilize
the capacitor sensor's properties for liquid-level measurement. The
interdigital electrode sensors illustrate more than one resonance at
the higher frequencies, and in this study, the first resonance
frequency fr
-has been utilized for the water level
measurement. Three water types are examined here: distilled, tap,
and river. The study assesses that with the transition of water, the
permittivity between the electrodes is changed and, it leads to a
change in capacitance hence, the change in resonance frequency was
observed. The proposed sensor can be represented by the lumped
element equivalent series RLC circuit. The developed IDE sensor has
good repeatability, small variability, and small hysteresis
error. The maximum standard error for distilled, tap, and river
water are 0.02833, 0.02503, and 0.02618, respectively, and the
hysteresis error is less than 1.903% of full-scale output
variation. The maximum error for the fr
estimation is about
±2 Hz.