Page 82 - Advanced Course

KNX ADVANCED COURSE

Figure 57: Group Object in ETS for reading the current brightness value

Figure 58: Blind control according to sun position

6.2.3 Wind sensor
This measurement instrument, which is actually one of the main components of a
meteorological station, has as a major role to measure the speed of the wind and transfer
it to the bus for further processing.
There are two different types of KNX wind sensors. The first type is the ‘Cup
Anemometer’, which comes in the form of the classical housing of a conventional wind
sensor but includes a BCU for the connection to the bus. The second type is the ‘Compact
housing’ similar to other sensors: this type has the advantage of low risk of damage
because of the lack of moving parts. Both housing types may be delivered with their
individual heating system in order to prevent them from freezing during cold days. For this
purpose, an ancillary voltage is needed, which can be fed by the ancillary voltage output
of a KNX power supply.

Figure 59: 'Cup Anemometer' and a 'Compact housing' wind sensor

The wind speed value is measured and expressed in meters per second and is
transmitted using a 2 byte Group Object with encoding 9.005, DPT_Value_Wsp, which
has a resolution of 0,01 m/s.

Figure 60: A typical Group Object in ETS for reading the current wind speed value

Home and Building Management Systems KNX Association
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