9.2.5.2 Humidity Sensor
Measuring range
Typical
Maximal
Unit
Accuracy
0 – 80
± 2
± 3
%
80 – 100
See illustration
%
Long-term stability
≤
0.25
% / year
9.2.5.3 Inaccuracies in Extreme Conditions
The capacitive humidity sensor consists of a thin polymer
film that is located between two electrodes. Depending on
the humidity, the polymer absorbs or releases vapor
contained in the surrounding air. This changes the polymer
film's dielectric properties and thus the sensor's capacitance.
This has the following advantages over other types of
sensors:
quick response
wide measuring range with an almost linear characteristic
curve
high accuracy and long-term stability
If the sensors are continuously exposed to extreme
conditions such as high temperatures, high aridity or high
Appendix
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