I'm building a house in Australia and wanting to use home automation. KNX has a number of advantages as a wired bus system compared to other wired and wireless systems. However, it has been very challenging and costly to understand what it offers and how I can integrate it. I want to use KNX, for some functions, but I need to integrate it with some other IP based equipment and other types of equipment. To do this, keep the costs down and maintain a good understanding of how all the technology works I want to ensure I can configure all the KNX components in my house. I would have thought KNX lite should be enough for this. However, the restriction of 20 devices means I would need to purchase the professional version to be able to make adjustments and well manage just my house (as I will have about 30 devices). I know there is ETS inside, but I think this is inadequate and lacks flexibility - not to mention clear documentation.
I don't understand the financial benefits to the KNX organisation re the selling and therefore the restricted distribution of ETS, however, I would have thought that:
1) KNX lite should be able to handle more than 20 devices - as my house isn't big and it will exceed the number of devices. I'd suggest 50 a more reasonable cap.
2) Home automation is developing very quickly now and I think KNX runs a real risk of being bypassed by the home enthusiasts (who are currently early adopters) by adding to the costs and charging for ETS and making it difficult and costly to use. I would strongly advocate that the ETS software is given away - at least for non commercial home use.
3) Finally I'd say that there is a dearth of clear, accessible technical information about KNX and ETS and the KNX organisation should really focus on opening things up to encourage people who are experimenting and moving home automation forward. If you compare KNX to Home Assistant - the KNX approach appears quite antiquated.