How many devices can be on a KNX System?

A single line can have 256 devices. 15 of these lines can be linked to an area and 15 areas can be linked to a backbone line. 256 devices can also installed on each of the area lines and backbone area lines but this includes any area or line couplers . This gives a total of 61696 devices.

Devices Per Line inc Line Coupler	256
* number of Lines	15
	3840
+ Devices on Line 0 inc Area coupler	256
	4096
* number of Areas	15
	61440
+ Devices on Area 0 inc IP Router at 0.0.0	256
Total	61696

The numbers above include the line couplers used to link lines and areas together but don't include power supplies as these don't have an address within the KNX architecture.

For more information on this, check out this essential guide.