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Basic FAQ

Answers to basic KNX questions

Know-How from the KNXperts

KNX Basic Knowledge

What is KNX, how does the standard work and why do you need the ETS? We answer fundamental questions on everything related to KNX in our basic FAQ.


Our KNX push-buttons are mounted in standard flush-mounted boxes. For this purpose, the enclosed mounting frame is screwed onto the flush-mounted box. The push-button is then simply plugged onto the frame, thanks to its spring clips it sits firmly in the frame.

All topologies except the ring structure are permitted. With the ring structure, runtime differences occur above a certain ring size, which means that data transmission is no longer guaranteed. In addition, the telegrams would "run dead".

According to DIN VDE 0815, the core identification for installation cables must be made as follows: Trunk 1: + red / - black, Trunk 2: + yellow / - white. Trunk 2 is only very rarely used for an auxiliary voltage.

Similar to an IP address, the physical address is an unmistakable identification of a subscriber in the network. It can be used to uniquely address the subscriber.

The group address defines the function of the participants. The system is programmed by assigning the group addresses to corresponding participants, e.g. which sensor should work together with which actuator.

Answers to specific product questions

Product FAQ

You didn't find the right answer to your general questions about KNX? We have collected more detailed, frequent questions about our KNX products in our product FAQ.

MDT product finder

Choosing between over 300 KNX products is not easy. To help you find what you are looking for quicker, we have created a product finder.

Die Beleuchtung: Licht – immer wenn Du es brauchst und in der passenden Beleuchtungsstärke

MDT solutions

How can a smart building be achieved with KNX, and what components are needed for this purpose? Have a look at the solutions.

KNX Technologie: Entstehung und Innovation – Alles rund um das Bussystem der Zukunft

KNX technology

KNX is a wired bus system for building automation, which controls areas of the building, links them together and coordinates them with each other.



We have put together all of the important files, such as KNX product databases and functional descriptions, clearly in our download area.

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