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General Information about
Anemometers
Anemometers measure air velocity. There are three basic types for different applications
all of which can be found on Technika:
Thermoelectric ("hot wire") Anemometers heat
a wire to a specified temperature and then measure the rate of cooling. This rate is
proportional to air speed. Thermoelectric measurement provides fast response times and
excellent sensitivity to very low air flows of <1 m/s but these probes are also the
most delicate of the three types and are not suitable for environments which are dusty,
humid ,corrosive, or where there are rapid fluctuations in the ambient temperature all of
which effect the rate of cooling. These Anemometers cover ranges of 0.01 ms ~ 5 m/s.
Vane Anemometers work on the principle that a
freely turning turbine will rotate at a speed directly proportional to the wind speed.
Vane Anemometers cover ranges as low as 0.15 m/s and as high as 40 m/s, or even higher by
special order. Useful for a wide variety of applications including relatively harsh
environments. Thresholds are not as low as with thermoelectric Anemometers since the vane
must overcome initial friction before it will turn.
Differential Pressure Anemometers actually
measure pressure which is then converted by the meter into air speed. Since differential
pressure probes are simple metal tubes with no moving parts they are the most rugged of
the three types of Anemometer probes and the only ones which can be easily cleaned. They
cover ranges of 1 m/s and up and are ideal for harsh environments.
Vane Anemometers
Thermoelectric Anemometers
Schiltknecht ThermoAir3
Differential Pressure
Anemometers
Schiltknecht ManoAir100
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