KNX + Homeassistant

Hi all

I’m new to Homeassistant and I’m looking for some guidance.

I’m trying to help out my dad. He built a home around 15 years ago and has KNX installed along with Gira Homeserver 3. That hardware is old, but working reliably. However, he has no access to modern features like automation, voice assistant control via Alexa/Siri and the like etc. I’d like to modernise the house.

I already installed Homeassistant on my Raspberry Pi and plugged it into his homework.

From what I’ve gathered so far, I will need a KNX IP interface to get KNX controllable over the network, so I found this, for example: ABB KNX IP-Schnittstelle IPS/S 3.1.1 - kaufen bei digitec

I have not ordered it yet because I wanted to see, via this forum, whether I’m on the right track :slight_smile: .

So I’m ready to connect the existing Gira Homeserver to the network. I’m still missing that IP interface, but once I order it, I’m unsure how to proceed.

Here is a picture of the Homeserver’s backside and the cable going into it that comes out of the wall.

I installed the KNX integration in Homeassistant but suppose I’m missing some instructions on the hardware side.

Can you give me any pointers?

I also learned about Homey Pro but I’m not sure how that compares to Homeassistant as I have no experience with either system yet.

This is the image of the KNX connection coming from the wall.

I also just realised that I suppose the Gira Homeserver already provides an ethernet connection. We also have a pretty basic HTML page with which it’s possible to control the lighting in the house as well as various blinds.

I guess the question is… do I want to completely replace the existing Homeserver with Homeassistant on Raspberry Pi as the new “brain” of the house or can Homeassistant play along with this Homeserver box?

Yes it should be fine.

You’ll need an KNX IP Interface (Weinzierl 732 or Enertex 1168 should work very well and are probably cheaper than the ABB thing you linked) as HA can’t use USB directly, and imho it’s not a good idea to mess with the existing Home Servers connection.

But more importantly, you will need the KNX project file and a ETS licence to be able to add that IP interface properly to the bus, add additional addresses you may need for HA and change device configurations. And when you change configurations you may want to do that in the Home Server configuration too so you need these project files too.

I don’t know if it can work as a KNXnet/IP interface. In theory that would be possible - if it does (maybe you’ll need to activate that somewhere) you wouldn’t need an IP interface.

There is also software that can be used to turn eg. a Raspi into a USB-IP bridge (Calimero or knxd). So you could run your HomeServer and HA via that USB interface you already have. But I’d consider this advanced KNX sorcery. I’d highly recommend to just get a decent IP interface :wink:


So, my takeaway from your message is:

  1. I need to get that KNX/IP interface to get started at all.
  2. I need the KNX project files and an ETS license. Now this might be a problem. I did not set up the initial installation myself, of course. A Swiss company called Feller ( did. This box is theirs and I have no access to its filesystem or anything. Perhaps, with some digging, I can get it… something to ponder, but not sure if worth the trouble :slight_smile:

Assuming I don’t want to mess with that existing Feller Homeserver box, what are my options? I obviously don’t want to break the house’s existing setup, but if I could set up an alternative that will work even better than what’s there now, I believe it would be worth it.