The Digitally Adressable Lighting Interface (DALI) is a digital protocol for the controlling of lighting in buildings (e.g. Ballast (electrical), Dimmer, etc.). In the field of telecommunications, a communications protocol is the set of standard rules for data representation, signaling, authentication, and error detection required to send information over a communications channel. ... Lighting refers to either artificial light sources such as lamps or to natural illumination of interiors from daylight. ... A ballast is a device used to start a gas discharge lamp, and, once the lamp is started, to limit the flow of electric current. ... Dimmers are devices used to vary the control the brightness of a light. ...

DALI was established as a successor for the still market dominating 1-10v and Open standard rival to DSI. DALI is standardized in accordance with International Electrotechnical Commission 60929, standard for fluorescent lamp ballasts. Open Standards are publicly available and implementable standards. ... The International Electrotechnical Commission (IEC) is an international standards organization dealing with electrical, electronic and related technologies. ...

Each operating equipment with a DALI interface can be communicated with over DALI individually. Using a bi-directional data exchange, a DALI controller can query and set the status of each light. As a “stand alone system”, DALI can be operated with a maximum of 64 devices. Alternatively, DALI can be used as a subsystem via DALI gateways. Two-way communication is a form of transmission in which both parties involved transmit information. ...

Advantages

DALI is an open standard not exclusively owned by a single company. It only requires one wire for up to 64 devices. Open Standards are publicly available and implementable standards. ...

Disadvantages

Each device gives itself a random number to identify itself, which makes inital installation and replacing faulty devices confusing as there is no indication which device is which, until you send out test signals and look to see which device responds. Being restricted to sixty-four addresses DALI cannot be used in large installations without using another technology to circumvent the limitation.

External links

Organisations

• AG-DALI, a working group set up by leading manufacturers and institutions in the field of digital lamp/luminaire control to promote DALI technology and applications

Manufacters of DALI Devices

• Osram
• Philips
• Helvar
• Spire Lighting
• Evolt lighting
• DALI EMERGENCY
• TridonicAtco