4.3811.00.000_US-Anemometer-DSP_eng.doc
10 - 26
021511/10/06
5 Calibration
The ultrasonic anemometer does not contain any adjustable components such as electrical or
mechanical trimming elements. All components and materials used show invariant behaviour in
terms of time. This means that no regular calibration is required due to ageing. Errors in measured
values are only caused by mechanical deformation of the transformer arms and associated
changes in measurement path lengths.
The acoustic virtual temperature can be used to check the measurement path length. A change of
0.17% in the measurement path length and thus a measuring error of 0.17% for the wind velocity
corresponds to a deviation in the virtual temperature of 1 K at 20°C. With a 6 K temperature
deviation there is thus a measuring error of approx. 1% for the wind velocity.
Important:
Mechanical deformation of the measuring arms results in
errors in the measured values, which involve the output of
error telegrams / error signals to the analog interfaces.
In the event of any change in the measurement paths of the anemometer the manufacturer should
be consulted regarding recalibration.
6 Warranty
Damage caused by improper handling or external influences, e.g. lightning, do not fall under the
warranty provisions. The warranty entitlement expires if the device is opened.
Important:
The ultrasonic anemometer must be returned in the original
packaging as the warranty entitlement otherwise expires with
mechanical damage, e.g. deformation of measuring arms.
