2

www.irf.com

IRPLDIM2E

Digitally Addressable Lighting Interface (DALI)

The Digital Addressable Lighting Interface (DALI), international standard prlEC929, is a communication protocol

and method to interface lighting units on a 2-wire network. The DALI protocol is 16 bits and supports addressing up

to 64 ballasts individually, 16 groups or broadcasting to the entire lighting network. Aside from the protocol, DALI

supports fading, logarithmic dimming, scenes and fault detection.

The DALI allows for a complete lighting environment to be controlled and managed efficiently. The DALI can control

(transmit and receive) up to 64 different ballasts with the same control system, transmitting instructions to single

ballasts or to a group of ballasts. The ballast provides eye sensitive dimming over a wide range (1-100%). Various

operating parameters can be changed and stored dynamically within the ballast memory. For example, scene

levels can be set for different groups of ballast. Also, maximum brightness, minimum brightness, fade-time and

several other features can be set as desired. Another feature is the ability to diagnose problems such as lamp failures.

Perfect Light Quality

By means of digital control, the light level can be adjusted very precisely according to individual lighting needs. The

DALI includes 256 levels of brightness and a logarithmic dimming curve (Figure 2). The use of this curve allows for

better control at lower light levels where the human eye is more sensitive.

0

15

30

45

60

75

90

105

120

135

150

165

180

195

210

240

255

225

0

10

20

30

40

50

60

70

80

80

100

Dim value

Relative lighting level %

Fig. 2 Dimming Characteristics