What is DALI?
DALI (Digital Addressable Lighting Interface) is an international standard (IEC 62386) for digital lighting control. Where KNX is a general-purpose building automation bus, DALI is purpose-built for lighting — individual fixtures are addressable, dimmable, and can report status back to the controller.
Many modern LED installations use DALI.
How DALI works
A DALI bus is a two-wire low-voltage cable (typically 16 V DC) shared between a DALI Master (application controller) and up to 64 DALI devices.
Each device on the bus has a short address (0-63), and the master sends commands to individual addresses, to groups (up to 16), or broadcast to all devices. Devices can also report back — a light can tell the master its current brightness, or a presence sensor can send occupancy telegrams.
The wiring is polarity-independent and doesn't need a specific topology — a DALI bus can be laid out as a line, a star, or a tree.
DALI versions
Two versions are common today:
- DALI (original / DALI-1) — single-master. One controller sends commands; devices respond.
- DALI-2 — multi-master. Multiple controllers can share a bus, sensors and switches are treated as first-class devices, and interoperability between manufacturers is formally certified.
Atios SmartCore is a DALI-2 multi-master controller — it can share a bus with other DALI-2 controllers. Atios KNX Bridge acts as the master on its own DALI bus.
Device types (DT)
DALI's "Device Type" extensions add capabilities on top of basic on/off and dimming. Both Atios devices support DT8 — tunable white and RGB/RGBW colour control for DALI lighting systems.
Typical DALI system
- DALI power supply — 16 V DC for the bus. Can be a dedicated PSU or integrated into the controller (both Atios products have a built-in 250 mA DALI power supply).
- DALI-2 Master (application controller) — sends commands, reads status. This is the role the Atios KNX Bridge or SmartCore plays.
- DALI drivers / luminaires — each with a unique address on the bus
- DALI sensors and push buttons (DALI-2) — optional, for occupancy, daylight harvesting, or direct wall control
Up to 64 addresses can share a single DALI bus. For larger installations, multiple buses or multiple masters are used.
Where DALI shines
- LED lighting installations where smooth, flicker-free dimming matters
- Architectural and commercial projects — hotels, offices, restaurants, shops
- Tunable white / circadian lighting scenes that need colour temperature control
- Projects where you want individual fixture addressing without running a separate switched circuit per light
How Atios uses DALI
Atios SmartCore acts as a DALI-2 Master on its own DALI bus. You address and group fixtures in the web-based DALI Configurator, then expose them to Matter via the Accessory Manager.
Atios KNX Bridge includes a built-in KNX-DALI Gateway. You run the same DALI discovery and grouping flow, then assign KNX group addresses in ETS so KNX switches can drive DALI lights directly.
Both devices support up to 64 DALI addresses and 16 DALI groups on their built-in DALI bus.