Product guide
7
Humidity and Dew-Point Instruments
Please note: Michell Instruments adopts a continuous development program which sometimes
necessitates specifi cation changes without notice. Please contact us for latest version.
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Long term measurement stability
The excellent metrological characteristics of the H5000
and H6000 ensure that short- and long-term drift are
minimized.
Under extreme and prolonged conditions of high humidity
(>95% RH), a drift may be observed, but it is reversible
once ambient conditions are restored.
Duration (DAYS): 1 7
Reversible deviation (% RH): 2% 3%
Long-term drift is low for a wide range of temperature
and RH values. Typically, for a 12-month period the drift
is less than 2%, measured at 75% RH and at ambient
room temperature.
Michell’s relative humidity sensors were originally
developed by the French company Coreci S.A. In 2008,
the Michell Group acquired the technology and the
dedicated team of sensor engineers in Lyon, France
that have developed the product line and achieved an
enviable, world-wide reputation for sensor quality and
performance.
The maximum upper limit of the operating range is
represented by the following water/air mixing ratios:
H5000: 250g water/Kg dry air, temp +200°C (+392°F)
H6000: 250g water/Kg dry air, temp +200°C (+392°F)
250g/kg dry air corresponds to 95% RH max at 70°C
(158°F) or 21% RH max at 99°C (210°F)
Typical response curve
This curve illustrates the large sensitivity range of
the sensor in terms of capacitance (pF) for 0 to
100% RH measurement range. See below for a typical
variation of approximately 86 pF for a 100% RH variation.
The key to the sensor’s performance is the design and
construction of the super-thin hygroscopic polymer
material that forms the dielectric of the sensor,
sandwiched between two conductive metal electrodes.
The outer electrode is engineered to have a porosity
specifi c to water vapor and therefore adapts extremely
quickly and reversibly to the prevailing humidity, giving a
large capacitance response and therefore high sensitivity.
The sensors and their components have been specially
designed and manufactured to provide excellent
metrological features while avoiding interference of the
measured environment.
Operating range
Michell’s H5000 and H6000 Series relative humidity
sensors have an extremely wide range of operation for
temperature and relative humidity measurements, making
them suitable for virtually any application.
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Humidity Sensor Technology
Relative Humidity Sensor tile layers
Glass substrate
Lower electrodes
Thin lm polymer
Upper electrode