Selecting technology for home automation

published 19.03.20225 min to read

Choosing technology for home automation is not an easy task, there are a lot of standards, technologies, and manufacturers. Each manufacturer promotes its products, and you can't immediately tell if this solution can do everything you want. Some solutions are more industrial (more robust), others are more hobby, but cheaper, and we don't always need the most expensive.

Not everything on the internet has reviews, so it's best to test it yourself. I have tried several solutions over the last 3 years (I don't remember all of them) and I think I have chosen some of the best available and most importantly functional ones.

Z-wave technology

The main thing I wanted is wireless technology because I don't want to pull cables everywhere and sometimes it's not even possible. There are a lot of devices that communicate with each other over Wi-Fi, but I Immediately excluded this option because:

unnecessary load on Wi-Fi network
the network must be separated so that each connected user does not have access to the communication
it's a clever idea to keep Wi-fi in reserve for other purposes (e.g. media sharing)
I would have to look for a devices that supports mesh connections so that there is no need for extenders

So, I kept looking until I found z-wave.

Z-wave creates a mesh wireless network where every device communicates with every. For info, the nodes that are connected to the power supply act as extenders and this means that the more nodes like this are in the network, the stronger and more stable the whole network is.

A mesh network has the advantage that each node/point/device connects ti as many other nodes as possible and communicates with them to transfer data as efficiently as possible.
wireless mesh network

Some advantages of z-wave (source $ z-wave web$ ):

easy installation
they consume extremely little power (I can confirm, some sensors have been on battery for about 2 years and there is still more than 50% battery life)
large community
several manufacturers
communication is secure (encrypted)

What you need to start a z-wave network

The main node of the z-wave network is called the gateway/hub, it stores information about the whole network and communicates with it. The master node can have different variants, most commonly:

USB Stick (just plug into USB, supports various systems)
extensions for other devices, e.g. Raspberry Pi
ready-made solutions called Home Centers

Aeotec Z-PI7

The first device I tried was the Aeotec Z-Pi (it may have been an older version than the one in the picture). It works by connecting to the GPIO of the Raspberry Pi and then serves as a gateway. I didn't have a good experience with it, everything was complicated to set up and then it only ran for a while. Probably by trying it many times adding, removing, reinstalling so the board stop working and reported some HW error. In the end I decided to go with a different solution.

I had a choice of USB Stick and Home Center. Since Home Center is an expensive thing and I wasn't sure if I would be able to edit/add custom logic somehow, so I finally decided on the USB Stick.

At the time I tried the Z-Stick there was a version about three times larger, it was called Z-Stick 5. The five had a button on the body that could be used to switch modes to add and remove devices from the network. I was happy with it, and everything worked well for me. When I started to deal with automation in the family home I looked to see if there were any new products and discovered the Z-Stick 7 and I still use it. So far, I have nothing to complain about it, it just took me a while to figure out how to add a new device to the z-wave network. The new version has no buttons, and everything must be controlled by the software. It can be used on Windows, Linux and OSX.

Aeotec Z-Stick 7

Raspberry Pi as the "iron" for z-wave gateway

For the z-wave gateway I started using the Z-Stick and it must be connected to something, so I chose my favorite mini pc - $ Raspberry Pi$ . I-ve been a fan since the first version, which I still have at home except it's no longer in use. I did my bachelor's thesis on the Raspberry Pi; it saved me when my graphics on my laptop burnt out and I quickly needed a pc at college, and I still don't understand how you can make a mini pc with that kind of performance for that price. I currently have five of these beasts connected at home (what I use them for, I'll describe in future posts). One of them right now has a Z-Stick 7 plugged into the USB and controls the whole household.

The mini-PC has Home Assistant OS installed, which is the best I've found for automation so far, and it seems to have no limitations. Short comparison next time.