ARS31(Pro)-UMB
Operating Manual V9/03.2017
G. Lufft Mess- und Regeltechnik GmbH, Fellbach, Germany
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setting, the sensor adjusts its dry threshold daily. If this function is disabled, the dry
threshold as set using the UMB-Config Tool applies.
If this value is too high, the ARS31Pro-UMB measures during dry conditions, which may
lead to incorrect measurements caused by condensation on the sensor element.
The calculation of threat of icing can be activated in configuration of the sensor.
The following parameters serve to configure detection of the threat of icing:
Time x describes the time for which the sensor cools down in order to cause the formation
of dew or frost.
Delta T (∆ T) is the temperature difference by which the road surface temperature cools
down in order to measure the threat of icing via the formation of dew or frost.
Delta T2 (∆ T2): If the threat of icing is detected via the temperature difference between
the road temp
erature and the freezing temperature, ∆ T2 describes the temperature
difference for which, upon lower deviation, threat of icing is transmitted. A value of -50°C
deactivates the calculation of threat of icing using the freezing temperature (available with
firmware release 10.3).
Delta LFM% describes the required change in the critical measurement variable for the
detection of the threat of icing. Higher numerical values reduce the probability of the
sensor transmitting the threat of icing and increase the stability of this function.
Figure 9: Configuration of ARS31Pro-UMB
