DALI, KNX or Zigbee?

Smart lighting is decided by the controls, not the lamp. The three systems that come up most often are meant for different jobs, and the choice is rarely a matter of taste; it depends more on the size and age of the project.

DALI

A digital, two-way protocol made specifically for lighting. Each luminaire gets its own address, can be controlled individually, and reports back if it fails. A single DALI-2 line holds 64 addresses, and the grouping can be reprogrammed in software at any time, so an office reconfiguration doesn't require pulling cables.

It belongs where many luminaires need individual control: offices, halls, showrooms, museums. It's also the standard solution for self-testing emergency lighting.

KNX

A building automation standard: it handles not only lighting but also shading, heating and ventilation, all in one logic. If lighting is part of a larger system, for example when the blinds and the lights respond to daylight together, KNX is the answer.

It's more expensive and requires a programmer, but it's vendor-independent and expandable over the long term. Often a combination of the two is optimal: KNX for the building, DALI for the lighting, connected through a gateway.

Zigbee and wireless systems

Meant for retrofits where there's no way to run new cable. In an existing apartment, this is often the only viable option, and today's range of devices is genuinely usable.

The downside is that it's a radio network: range, reinforced concrete walls and the number of devices all affect reliability, and the system is typically tied to one manufacturer's app, sometimes to its cloud service. Over a ten-year horizon, that's a risk.

The order of decisions

For new construction, it's almost always worth designing a wired system, even if only the cable goes into the wall in the first phase and the controller comes later. The protocol alone isn't a plan, though: first you need the zones and scenes, and only then what controls them.