Page 72 - Advanced Course

KNX ADVANCED COURSE

As air conditioners currently on the market are not always natively equipped with a KNX
interface, it is useful to consider the used type of communication.

4.3.3 Unidirectional Communication

With unidirectional communication you only have the option of communicating to the air
conditioner. This solution does not allow an information flow back towards KNX.
Consequently, you have the possibility of setting the temperature or the number of
rotations of your fan, however you will not receive any confirmation of this action on KNX.

4.3.4 Bidirectional Communication

In the case of bidirectional communication, you can both send and receive telegrams from
either direction. Thus you will also have the possibility to influence the performance, that is
to say the actual operation of the air conditioner, as well as the possibility to receive
feedback from the device. This type of integration has the advantage of gathering,
processing and logging process and operation information centrally. This can even go so
far as registering error indications, which can in turn lead to a consecutive reaction or the
sending of an error message.

The implementation of the integration can be realized with the following media:

Infrared
Twisted Pair
Ethernet/IP
RS232
RS485
…

Figure 45: Integration of Air Conditioner via IR-Gateway

Home and Building Management Systems KNX Association
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