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Functional Principle, Technical Data
combiSENSOR 64x0
T<A
Sensor
W
orking distance S (= eddy)
A
T
W
orking distance
Ground electrode
Target
Insulator (
r
)
Fig. 2 Sensor arrangement for thickness measurement
The thickness of the insulator is calculated from the following factors: max. working distance, capacitive dis-
placement signal A and the dielectric constant of the insulator:
T = S (eddy) - A (capa) *
r
r
1
* + Offset
WD
100 %
T
Target thickness [µm]
S
Signal eddy sensor [%]
A
Signal capacitive sensor [%]
ε
r
Dielectric constant (insulator)
WD
Working distance [µm]
Offset
Constant [µm], standard value = 0
