Capacitive displacement sensor: Difference between revisions

Revision as of 23:00, 24 October 2023

Revision as of 05:13, 31 October 2024

Line 4:

==Basic capacitive theory==

Two identical parallel conductive plates of area <math>A</math> separated by a gap of distance <math>d</math> will have a [[capacitance]] <math>C</math> of:

[[Capacitance]] is an electrical property which is created by applying an [[electrical charge]] to two conductive objects with a gap between them. A simple demonstration is two parallel conductive plates of the same profile with a gap between them and a charge applied to them. In this situation, the Capacitance can be expressed by the [[equation]]:

:<math> C = \dfrac{\varepsilon_0 K A}{d} </math> <ref name="Physics">{{cite book|isbn=0-87901-135-1|title=Physics Second Edition|author=Paul Allen Tipler|pages=653–660|publisher=Worth Publishers|year=1982}}</ref>

Wherewhere ''C'' is the capacitance, ε<submath>0\varepsilon_0</submath> is the [[permittivity of free space]] constant, and ''<math>K</math>'' is the [[dielectric constant]] of the material in the gap, ''A'' is the area of the plates, and ''d'' is the distance between the plates.

There are two general types of capacitive displacement sensing systems. One type is used to measure thicknesses of conductive materials. The other type measures thicknesses of non conductive materials or the level of a fluid.