Digital Addressable Lighting Interface

What is DALI?


DALI as an acronym stands for Digital Addressable Lighting Interface. DALI as a concept stands for an intelligent lighting management system that provides increased energy savings,easier installation and maintenance and maximum control and retrofit flexibility.It is an entirely open standard.

DALI is not a single product. It is an industry protocol that allows components from different manufacturers( ballasts, controls  systems,sensors,controllers,switches etc) to be mixed and matches seamlessly into complete systems. With DALI, design and user flexibility is dramatically improved over conventional,proprietary systems.
Traditional Lighting controls utilized analog interfaces or proprietary digital control methods.
image courtesy Dalibydesign


DALI advantages to Lighting designers


  • Simple wiring of the control wire
  • Control of individual Lights
  • Flexible Group control
  • Software control allows easy configuration and modification
  • Simple interface with Building Management Systems(BMS)

DALI advantages to Facility Managers


  • Increased Space Felxibility
  • Simple modification
  • Lower maintenance costs
  • Energy Savings

DALI advantages to Building Occupants


  • Customized Lighting Preferences
  • More comfortable lighting
  • Individual controls
  • Easy modification
Features available when installing DALI ballasts are:
      • Simple wiring of control lines (no group formation, no polarity).
      • Control of individual ballasts or groups is possible.
      • A simultaneous control of all ballasts is possible at any time.
      • Ballasts status messages (lamp fault ....).
      • Automatic search of ballasts.
      • Automatic and simultaneous dimming of all ballasts when selecting a scene.
      • Logarithmic dimming behavior – matching the eye’s sensitivity
      • System with assigned intelligence (every unit contains amongst other things the following data: individual address, group assignment, lighting scene values, fading time ....).
      • Operational tolerances of lamps can be stored as default values (for example for the purpose of energy savings maximum values can be set)
      • Fading: adjustment of dimming speed
      • Options for emergency lighting can be chosen (selection of specific ballasts, dimming level)
      • No need to switch on/off the external relay for the mains voltage (this is done by internal electronic components)
DALI has been defined for:
      • a maximum of 64 single ballasts (individual addresses)
      • a maximum of 16 groups (group addresses)
      • a maximum of 16 scenes (scene light values)
Each ballast stores its own set of parameters:
      • Individual addresses
      • Group assignments
      • Light scene values
      • Fading times
      • Emergency lighting level (System Failure Level)
      • Power On Level
Information on DALI technology and a list of existing ballast manufacturers can be found at AG DALI association’s website (http://www.dali-ag.org).



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