KNX Basics

When thinking in terms of a roller shutter, it is most natural to consider it 100% open; one expects the maximum amount of light from the outside to enter the room.

It counterintuitive to me that in KNX is roller shutter positioning with DPT 5.001 is:

0% = fully opened

100% = fully closed

Wouldn't it be more natural to express the percentage of opening, rather than the percentage of closing?

This would also be consistent with how we naturally interpret other quantities, such as light level: 0% means no light, 100% means maximum light.

DPT 5.001 is a generic percentage is this relate to the Up/Down commands?

So my questions are:

Where is the conventional mapping (0% = fully raised, 100% = fully lowered) formally specified?

Does this change from a manufacturer and another?

Why represent shutter position as a percentage of closing rather than a percentage of opening?

If interoperability depends on conventions that even manufacturers describe as unwritten, shouldn't these semantics be explicitly documented?

I bought a house with Gira KNX installation (HomeServer 3), Gira fingerprint sensors for the doors.

One of the doors keep opening on an inconsistent interval without being actively triggered via the app.

Access of the previous owner can be excluded, so anyone else from my household.

How can I figure out where the command to open the door comes from?

After some research (and this post, thanks again!), I became very interested in buttons where you can switch between one or two rockers/Wippen. Cause for multiple rooms I'm not 100% sure if we will be fine with one or two, so this is rather handy.

In case anyone else is interested, I'm just leaving this here, so you don't have to do the research:

In case I missed any, sorry! Happy to add more to the list. I'm from Germany, prices for you might be different of course..

I hope this is a good location to share this.

Hi r/KNX,

I'm Manuel from Swisstoggel, a small developer in Switzerland. I've built **Swisstoggel KNX**, an app that controls a KNX installation directly over your KNX IP interface or IP router. No extra server, no account, no cloud. It's now in a closed beta on Android and I'm looking for testers with real installations.

**What it does**

- Works with any KNX IP interface or router, any brand (tunneling over UDP and TCP, routing via multicast)

- Imports rooms and functions from your ETS project (.knxproj from ETS4/5/6, also password protected) or a group address export

- KNX IP Secure and Data Secure, keys from your .knxkeys file, stored only in the phone's keystore

- Lights (switch, dim, tunable white, RGB/RGBW), blinds with position and slats, heating with setpoint and mode, fans, scenes, measured values, text messages

- Floor plan with layers: import your plan as image or PDF, place functions on it and see the state of every light or blind at a glance

- Own app scenes, started from a home screen widget, quick settings tile, voice command or an NFC sticker at the door

- Group monitor for installers: every telegram with readable values, send telegrams, name unknown addresses

- Demo mode with a full simulated apartment, so you can try it without an installation

**What it doesn't do (yet)**

- No cloud remote access by design. From outside you use your own VPN

- No schedules or push notifications, the installation itself usually handles that

- iPhone version is coming later; the beta is Android only

**Pricing:** free to download and set up, with 5 operable functions. The full version will be a one-time in-app purchase of 29 CHF. No subscription, no ads, no tracking.

**What I'm looking for:** people with a real KNX installation who use it for two weeks and tell me what breaks, what's missing and what's confusing. Different interfaces (ABB, MDT, Gira, Weinzierl, Siemens...) and larger ETS projects are especially welcome.

If you're interested, sign up at https://www.swisstoggel.ch/beta and I'll add you to the test.

A short video of the app: https://youtu.be/IUXnza2Uq7U

Happy to answer any questions, also the technical ones.

Manuel / Swisstoggel

Hello,

I'm trying to understand the difference between the Zennio DALI BOX Broadcast interface (for example model#ZDIDLB6V2) vs the DALI BOX Interface 64 X2 other than the 6 channels vs 2 channels difference. The broadcast interface is listed as a single-master vs. the the other one being listed as a multi-master. But everything I've read seems to indicate that operating a DALI system (not to mention a Dali-KNX system) in multi-mastee mode is not something that is ready for primetime.

I guess my question is that if it's used as only a single master device, is there any advantage of going with the BOX interface 64 X2?

Thanks in advance for any inputs and pointers.

Hi guys
Been looking at different light switches for a while and have decided that I like the JUNG F40 quite a bit, but I do think they are rather expensive with the price being 150€ each.

What are are you guys running and why?

Here is a link of JUNG F40: https://www.jung-group.com/en-DE/Catalogue/KNX/Manual-sensors/F-40/?p=1&properties=e7066646b4b31b6f3cf5a4340ee9afe0%7C1cbad5e11deae4fe2ce36ea6f208da45

I am using an EK-BF1-TP to control a DALI light, and something weird is going on when I try to power them on and off. In the video, you can see light addresses 4 and 40 seem to be linked together, as when I press power off on one, the other's value moves.

Also, they seem to not be fading down to min/max properly, as when I press off the value drops to 0%, then increases again. Vice versa it will happen when pressing light on, it will increase to 100% and then drop down.

Does anyone know why this could be happening?

I have a paid ETS license and want to connect an AI assistant to ETS through MCP to help manage group addresses, rename devices, check configurations, and automate repetitive work on my own installation.

That led me to ETS Power Editor. Its regular price for editing functionality is €49.98/month. Reading and monitoring are free, but making changes requires the subscription. That is almost €600/year, on top of ETS and any AI subscription. For a homeowner maintaining one installation, that feels absurd. Pricing.

The bigger issue is KNX Association’s approach to community development.

According to KNX’s documentation, becoming an ETS App developer requires organizational membership, a Manufacturer Code, and a developer agreement. Even running a non-validated add-in requires a separate developer/test license; owning ETS is insufficient.

A community MCP bridge for ETS already exists on GitHub, but it encounters precisely this licensing barrier. People are already building alternatives, the obstacle is getting them running through the supported route. Community project.

I believe that if KNX opened development to individuals, the community could build and maintain free integrations alongside commercial products. Commercial developers could still charge for advanced features, support, and convenience.

Look at Microsoft: Code OSS, the foundation of VS Code, and .NET are developed openly. Developers can experiment and contribute without first joining an industry association.

Why can’t licensed ETS users have a free developer mode, accessible SDK documentation, and the ability to run community add-ins with explicit consent? Permissions, backups, change previews, and audit logs would help address safety concerns.

I want to see KNX remain relevant and attractive to developers. Making it difficult for enthusiasts to improve software they have already paid for seems counterproductive.

Has anyone found a supported, affordable route for individual ETS App development? And would you support KNX opening this up to the community?

When I save my ETS project locally I always click the little icon to create a backup drive. Today I tested those backups out and the last 3 are corrupted archives. They have various header issues.

I had to go all the way back to March 2026 to find an intact backup!

Hi! We are renovating our house and I want to switch to KNX. Now the decision is already final basically, but I'm unsure about the switches. I did some research and found this one from Weinzierl:

https://weinzierl.de/de/produkte/knx-tp-push-button-420-1-secure/

It looks pretty very interesting to me, especially because you can switch between a single and double rocker setup and it's even cheaper as MDT (at least where I'm from/Germany). And as I'm unsure yet about some of the configurations I really like the idea of using this everywhere and then later deciding on the exact setup and whether I need 2 or 4 options.

However, except for one youtube video, I can barely find any real-world review or experiences with it. Are there any downsides or limitations I'm missing? Or is there a reason why this switch doesn't seem very popular compared to MDT/Gira?

Thanks!

Hi! I'm new to KNX and ETS. I recently took over a house with a 2008 Berker installation, including an old Berker MT 701 CT touch panel. It still works, but I can't edit it in ETS6. The old ETS3 plugin fails on project import, even in 32-bit compatibility mode, and the device stays at "Re-import of product data required".

Has anyone got the MT 701 CT plugin working in ETS5/ETS6? How did you fix it?

Thanks!

Hello, KNX Ultimate for Node-RED 8.0.6 is out. Also KNXUltimate 6.0.8 for Node JS has been released.
For a limited time only, you can download and use it in your home or commercial project, totally for free.
When this limited time offer expires, you can download and use it in your home or commercial project, totally for free.
This means open source.
Subscribe to the dev's channel.

There is nothing quite like a well-organized KNX distribution board. Whether you use dedicated terminal blocks for every core or wire directly into the actuators, the way a rack is dressed says a lot about the integrator.

Post a photo of a project you are proud of, or even a nightmare cabinet you inherited that you are currently trying to fix.

Are you a fan of using massive trunking to hide the slack, or do you prefer the look of exposed, perfectly combed looms tied with velcro? Or do you choose chaos?

Show us your box! (SFW only plz)

In ETS6, I want to produce in the following manner:

• Create my base five different room types. Finished build of a room type contains: a room and the devices set up for the type, group adresses after a syntax that get replaced for each room to make them unique, central adresses are linked.
• Have a program that produces my 300 rooms based on the different five room types
• Commission the project.
• Deliver one consistently programmed project.

I see some reddit posts revolve around creating the adresses, this seems cumbersome, and also each human involvement in linking is an opportunity to create another mistake. And we know you make them too.

• Ref: I got tired of building KNX group addresses in Excel. : r/KNX

Today I create the room types, and copy / paste special / search replace for production. I want the machine to do the production part.

Any tips?

Does anyone have any recommendations for KNX system designers / installers in South Florida? I am looking at this as a better alternative to Lutron RA3 for new build.

Hi,

We have a knx project with an old MT701 display (ETS3 plug-in, 32-bit compatability mode). In the summer we removed this device, and replaced it with a Zennio display.

I just deleted the device from the building view, as it is tossed now. After this I restarted the project on my computer on 64-bit mode without any problems. However I now bought a new computer, and tried to import the project now (did an export today), but I can't seem to be able to import it. First it says I have to restart ETS6 in 32-bit mode, and after I have done this it ask me to install the plug-in.

Is there any way to fully remove the device from ETS, so I don't need to install the plug-in on the new computer? I still has access to the old computer.

Hello, i was wondering if someone is using ETS on a Linux machine. I am currently in a testing phase (Virtual Box), since i want to switch to cachy os. My pc got old and is not win 11 upgrade able, and therefore i want to give my old friend a second life by installing a linux distro.

The only big thing which is stopping me is ETS, i was able to install it but could not open it. And on the other hand i am also not sure if this is a reliable and stable solution. i dont want to end up, not beeing able to change my knx setup at home, if i wish to.

Thanks for your input and your help.

Edit: sorry for the spelling error in the title, i cannot change it anymore...

Hi everyone,

I’ve seen a few posts here about using KNX cable in Canada, but it seems like there still isn’t really a CSA-approved KNX cable available here.

I’m stuck on a situation where I need to run the KNX communication cable into the same single-gang box as the 120VAC wiring. From what I understand, the code doesn’t allow that unless the communication cable has the required insulation/separation rating (e.g. tested to 4kV).

The problem is, I can’t seem to find any CSA-approved KNX cable that meets this requirement.

So what are my options here? Has anyone in Canada actually dealt with this before? What cable or method did you use?

I’m honestly pretty stuck on this one! 😅 Any advice would be really appreciated.

What I want to do: rip out the whole KNX system and move to Home Assistant or Homey. Good news is it's star wiring — every switch and light point already runs its own cable back to the panel. Bad news: the wall switches only get a thin KNX bus cable (4 wires, 2 apparently unused), not mains — so I'm thinking of using those 2 spare wires as a dry contact/switch input into DIN-rail relays (Shelly Pro line) instead.

Questions for people who've done this:

**•** Has anyone actually gone KNX → Home Assistant/Homey while keeping the existing home-run wiring?  
**•** Does the "2 spare bus wires as a switch input" trick actually work in practice, or is it more trouble than it's worth?  
**•** Room-by-room DIY, or is this a job for an electrician from the start?

Any pitfalls, war stories, or "wish I'd known this before I started" welcome.

I’m about to purchase ETS6 Professional for professional KNX integration work and I’m trying to decide whether I should add the ETS6 USB licensing dongle or just use the cloud license.

The dongle is an additional cost, so I’m mainly interested in hearing from people who actually use ETS6 professionally.

My situation:

I’ll be using ETS6 for KNX integration and commissioning

I’ll be working on projects at different client sites

I may use ETS6 on more than one computer/laptop over time

I’m based somewhere, where the Internet connectivity at some project sites can occasionally be unreliable

I’m not particularly concerned about the additional €80 cost itself. I’m more interested in whether the dongle provides a meaningful advantage in day-to-day professional use.

For those who have used both:

Would you personally buy the dongle if you were purchasing ETS6 today?

I’d especially like to know:

How useful is offline operation in real-world commissioning?

Is moving the dongle between computers convenient?

Have you had any issues with the dongle/license?

Are there situations where you wished you had chosen the cloud license instead?

If you lost/broke the dongle, how painful was the replacement process?

For a professional integrator, is there any other reason to specifically choose the dongle?

I’m looking for real-world opinions rather than the official KNX feature comparison, so please share your experience, including reasons not to get the dongle.

Thanks!

As seen in the photo RX and TX signals are not lighting. And we cannot command VRV indoor unit from touch panel. But if I will remove this gateway and put another room, signals start lighting and we can command VRV IU by touch panel. In total 80 indoor unit gateway ,11 was like this. But today also another room joined and it is 12 now. Supervisors tried a lot but still not solved issue. Can anyone please help?

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Hi everyone,

I’m curious to know how other KNX programmers/companies estimate the cost of programming and commissioning for a project.

Do you use any kind of standard pricing model or ratio? For example:

Number of KNX devices (actuators, sensors, push buttons, gateways, etc.)

Number of physical inputs/outputs or I/O points

Number of group addresses

Number of rooms/zones

Number of electrical panels

Project floor area (€/m²)

Number and complexity of HVAC systems

DALI integration

Energy metering / energy management

Logic/automation complexity

Supervision/webserver (e.g. Gira X1/X2, Domovea, Thinknx, etc.)

Integration with third-party systems

ETS engineering/documentation

Commissioning and on-site testing

I’m also interested in whether you use a percentage of the KNX hardware cost as a starting point for the engineering/programming cost.

For example, if the KNX material has a net value of €40k, would you typically estimate programming as 10%, 20%, 30%, etc. of the hardware value — or do you avoid this approach altogether?

Another question: how do you deal with repetition?

For example, if a hotel has 100 similar rooms with essentially the same KNX configuration, do you significantly reduce the programming cost per room because the solution can be replicated, or do you mainly price according to the total number of devices/I/O points?

And conversely, if you have a smaller project with only 20 rooms but each room is highly customized, would you charge considerably more per device/room?

Finally, do you normally take the type of project into account (residential, hotel, office, hospital, industrial, student residence, etc.)? If so, how much does this influence your price?

I’m trying to understand whether there are any useful benchmarks or ratios in the KNX industry, such as:

€/KNX device | €/I/O | €/room | €/m² | % of hardware cost | €/engineering hour

Obviously every project is different, but I’d really appreciate hearing how experienced KNX programmers approach this in practice.

Thanks!

Hi everyone,

I’m an Electrical Engineer and KNX Certified Partner currently working as a Presales Engineer in Smart Lighting & Building Controls.

I have hands-on experience with KNX, DALI, KNX-DALI integration, smart lighting, Schneider Wiser/Zigbee, DIALux, BOQs, technical proposals, tender packages, system selection and coordination with clients, consultants and contractors. I’ve worked on 150+ residential and commercial projects.

I’m currently looking for opportunities in Europe, particularly in the UK, Germany or the Netherlands, where I can grow further in BMS, Building Automation and Smart Building systems.

I’m based in Egypt, so I would need visa sponsorship. If you know of companies hiring junior/early-career KNX, BMS, Building Automation or Smart Lighting engineers and willing to sponsor international candidates, I’d really appreciate any recommendations or connections.

Happy to share my CV. Thank you! 😊