Blind control for new construction (Many units per switch box)

Let's put it this way, I'm probably the DAU in our family! )

So I'd prefer classic light switches (-buttons) for simple on and off. Dimming, like with a Tronic dimmer, I also understand.
I see a multiple division of control areas on a switch panel as useful for roller shutter control, for example, since it saves space with switch positions, or for switchable sockets.

But the combination of ring installation and tree structure is also possible according to my current reading, right!?
I'm just thinking that, for example, in a ground floor wiring, the ring is laid in one main direction, but a sensor unit on the opposite side still needs to be operated.

When does a KNX line have to be laid to a load? Like with venetian blinds/roller shutters, lights, sockets?

Questions upon questions!

Best regards,
Thomas

When does a KNX cable have to be laid to a load?

Not at all. Because it is a data cable.

The KNX cable simply has to be at every point where a KNX device is or will be.

In the minimal setup, roughly like this:

from the distributor (which contains the actuators, power supply, and interfaces) to the switch/button (called sensor in KNX language)

That's it...

Of course, you wouldn't necessarily do it that way, but it would work.

Another advantage of KNX, especially if no cables are yet installed. You can put it together however you want. At the entrance door to the living room, a simple button (with KNX inside) with which you can turn the light on/off/dim and (if needed) control 2 groups.

And at the terrace door/on the sofa or wherever, touch sensors with any number of functions for light, blinds, air conditioning, heating, weather forecast, alarm messages, temperature display, etc.

An NYM cable at the light switch in this scenario wouldn't be the fifth but rather the sixth wheel on the wagon. As unnecessary as a goiter.

Of course, assuming everything is controlled via KNX in this room(s).

The other rooms can still be wired conventionally.

Here is a picture to illustrate the system:



And here, very simply, broken down completely into a conventional two-way switch and KNX.

I recommend making a plan for the entire house: where would you like to have what (dimmable/colored light, roller shutter control, visualization, switches, presence/motion detectors, window contacts, etc)? And not "what can I currently afford?" but really "what would I like (if I had won the lottery)?".

Accordingly, the basic installation, i.e., the wiring, should then be carried out.
The additional effort compared to a conventional installation is actually quite limited. Especially if you are a professional and can do a lot yourself.

Afterwards, you can consider how to gradually expand the functions.

Starting with a 20-channel switching actuator for the lighting throughout the house. Possibly a 4-channel or 8-channel dimmer, two roller shutter actuators, and you have the basic functionality covered for around €2,500 (including power supply and interface).
ETS5 Lite is sufficient for this, and parameterizing these functions is actually quite simple.

If there is money left, the first presence/motion detectors can be added, lighting circuits grouped into scenes, a roller shutter automation (with weather station) implemented, a night mode realized, and so on...

Imagine you only equip two or three rooms with KNX and would (and you will, I put my hand in the fire on that) then also like to dim the lights in the fourth room or implement a "central OFF" function at the front door.
That won't work.

Therefore:
everything that is permanently installed and cannot (or only with huge effort) be changed later – i.e., the cables – should be fully installed from the beginning,
everything that can easily be retrofitted will be implemented when possible and/or desired.

Hey!

I think it’s getting better and better!

Are the window contacts even worth it if you don’t install them right away?
Burglary alert and window opening status, right?
Don’t the roller shutter motors need a KNX cable connected? There are also limit switches installed there, and if blinds are to be adjusted accordingly...

While reading further, I came across the company Hager and their KNX-easy product.
Unfortunately, it is described very briefly on the homepage.
Does anyone know what the advantages are?
The system is supposed to be compatible with the ‘conventional’ KNX.

Have a great weekend, everyone!!

Hi,

usually only 5x1.5 cables go to the roller blinds, the actuator is located in the distributor, the rest is configuration in the ETS. Optionally, you could also pull a green KNX cable to each socket in order to check the window contacts in the socket as well.

BUT every window contact costs you between 50 and 100€ from the window manufacturer and each pill for the KNX bus costs about 40€ more.

That is one of the reasons why people always say KNX is SO expensive. Suddenly, the demands increase and all that costs EXTRA. You don’t even talk about such things when doing standard electrical work.

Hager EASY is the attempt to sell KNX light to people. Personally, I consider that to be an insult to intelligence. B&J do this perfectly. They sell their Free@Home as THE solution, and that stuff isn’t even cheaper and is actually crippled in functionality compared to the 'same' components in KNX... But mankind wants to be deceived!! It’s like putting a sign in the supermarket saying 'SPECIAL OFFER' and then people buy it. And most of those who bought it only realize later that they are restricted. This is especially extreme with the sensors. For KNX you get push buttons starting at about 60€, even from 40€ if you put a pill in the wall and use a classic switch. With B&J in Free@Home they basically do it like the pill solution in KNX. Only they sell it to you as a 'switch'. The single one for 35€, the double for 45€ and so on. The actuators cost MORE than with KNX and once you have Free@Home you’re stuck. With KNX you get whatever you like from any manufacturer and it works!!

And a lot has happened with KNX programming as well. There is now ETS Inside which costs 160€ and has the limitation that you can only program one line and a maximum of 255 devices. But for a single-family house that is more than enough. And you don’t limit yourself in the choice of your devices. So I can only recommend everyone to rely on KNX for home automation.

Jus my 2 Cent

Don't the blind motors require a KNX cable? There are also limit switches installed there, and if the venetian blinds are to be aligned accordingly....

It depends on what you install there. For motors with direct KNX connection - yes
for others - no

As Tom already wrote, it gets expensive with the window contacts, but precisely because with conventional systems they are not installed at all, this position is missing for the average homeowner and then the discussion starts: KNX is luxury, and the pharmacy etc. etc.

However, one should compare apples with apples and pears with pears.

With KNX, appetite comes when eating and so it simply becomes more and more in the end.

BUT: You don't have to install everything right away. You just have to make a plan where, how, why everything should be controlled later and at first (for the hundredth time now the tip) lay KNX cables everywhere!

Additional cost: maybe 100 euros
Flexibility and expandability afterwards: priceless.

Whether you install window contacts or not is up to you.

I use mine for alarm, roller shutter control, status indication, light control. Two per casement cost me an additional 50 euros including KNX connection. But as I said, you don't have to do it. In the minimal setup, however, I would definitely install some at the doors where you constantly go in and out.