DALI-2 lighting control
DALI-2 lighting control, explained.
DALI is the open digital standard for commercial lighting control. Every driver, sensor and push button on the line has its own address, so lighting can be grouped, scened, monitored and changed in software rather than rewired. DALI-2 adds certified sensors, push buttons and controllers, so products from different manufacturers work together.
What DALI is
One digital language for every light fitting.
DALI stands for Digital Addressable Lighting Interface. It is defined by the international standard IEC 62386 and maintained by the DALI Alliance.
Instead of switching whole circuits, a DALI controller sends commands over a two-wire control bus to individual LED drivers and other control gear. Devices can also report back, which makes DALI useful for maintenance and energy management, not just switching and dimming.
- Individual control
- Every LED driver has its own address, so any light can be switched or dimmed on its own, whichever circuit it is wired to.
- Groups and scenes
- Lights are assigned to groups and scenes in software. Each DALI line supports up to 16 groups and 16 scenes.
- Two-way feedback
- Controllers can query devices for status and faults, such as a failed lamp or driver, rather than waiting for someone to report it.
- Change without rewiring
- When a floor is refitted or re-tenanted, zones and scenes are reprogrammed instead of rewired.
How it works
How a DALI-2 line comes together.
A DALI line is a two-wire bus. It carries control data, not mains power, and needs a DALI bus power supply. Some application controllers and gateways include one, so check the product before designing the line.
Application controller
Runs the logic: groups, scenes, sensor responses and schedules.
Bus power supply
Powers the DALI line itself, separate from the lighting load.
Control devices
Sensors and push-button couplers report events and measurements.
Control gear
LED drivers, dimmer and relay modules act on commands.
- 64 control gear addresses per line
- 64 control device addresses per line with DALI-2
- 16 groups per line
- 16 scenes per line
- 250 mA maximum bus current
- 300 m maximum line length
Figures are per DALI line under IEC 62386. Real designs are also limited by the bus power budget, cable size and each manufacturer's specifications.
DALI and DALI-2
What DALI-2 changed.
The original DALI standard covered control gear only. Sensors and push buttons were proprietary, so mixing brands was unreliable. DALI-2 standardised the rest of the system.
| Feature | DALI | DALI-2 |
|---|---|---|
| LED drivers and control gear | Standardised | Standardised, with tighter requirements |
| Sensors and push buttons | Manufacturer-specific | Standardised as control devices |
| Application controllers | Not standardised | Standardised, including multiple controllers on one line |
| Certification | Self-declared | Tested and registered through the DALI Alliance |
| Mixing brands | Often limited to one brand's sensors and controllers | Designed for multi-vendor systems |
DALI-2 control gear can generally be used in existing DALI installations, but mixing generations should be checked at design stage.
DALI with KNX
DALI on its own, or as part of KNX?
Both are open standards and they work well together. The right choice depends on whether the project is lighting only or the whole building.
Products
DALI-2 products at Kadan.
- DALI-2 sensors Steinel presence, motion and light-level sensors that connect to the line as DALI-2 input devices.
- DALI-2 application controller The Steinel DALI-2 application controller for the LiveLink system.
- DALI-2 push-button couplers Connect conventional push buttons to a DALI-2 line.
- DALI-2 dimmers and relays Dinuy dimmer, relay and RGBW modules controlled over DALI-2.
- KNX–DALI gateways Connect DALI lighting lines to a KNX system.
FAQ
Common questions about DALI.
What does DALI stand for?
Digital Addressable Lighting Interface. It is an open international standard for digital lighting control, published as IEC 62386.
What is the difference between DALI and DALI-2?
DALI-2 extends the standard to sensors, push buttons and application controllers, and requires products to be tested and certified. The result is dependable interoperability between brands.
How many devices can one DALI line support?
Up to 64 control gear addresses and, with DALI-2, up to 64 control device addresses per line. The bus power budget and each manufacturer's limits also apply. Larger buildings use multiple lines.
Does the DALI bus carry mains power?
No. The DALI bus carries control data and needs its own DALI bus power supply. Drivers and luminaires are powered separately by mains wiring.
Can DALI and KNX be used together?
Yes. A KNX–DALI gateway connects one or more DALI lines to KNX, so lighting can be controlled from KNX switches, sensors and visualisation alongside other building services.
What is DALI DT8?
Device Type 8 is the part of the DALI standard for colour control, such as tunable white and RGBW. Both the driver and the controller must support DT8.
Planning a DALI-2 project?
Tell us about the building and we will help you choose the controller, sensors and control gear, or put you in touch with an integrator.