5
ABB i-bus
®
KNX
Introduction
1.2 What
is
DALI?
1.2.1
DALI as stand-alone
system – characteristics –
The requirements for modern lighting technology are extremely varied.
While previously lighting was only required for visual tasks, nowadays
factors such as comfort, ambience, functionality and energy saving are in
the foreground. Furthermore, a modern lighting system is increasingly being
incorporated in the Facility Management (maintenance and preparation
management) of the building installation. Often, a complex lighting manage-
ment system is needed which meets the uses of the premises. All these
requirements are either not adequately met by the traditional analogue
electrical installation or only with considerable effort and cost. The DALI
standard has emerged from this background.
The manufacturers from the lighting industry, primarily the leading
manufacturers of electronic ballasts, joined together to define a new
standard for the digital communication of a lighting system. This resulted in
the DALI protocol (
D
igital
A
ddressable
L
ighting
I
nterface).
The DALI standard enables addressing of up to
• 64 devices with a DALI interface
and compiling these devices into
• 16 lightscenes (incl. dimming values and transitional periods) and
• 16 lighting groups (multiple assignments of the devices are possible).
Fig. 2: DALI block diagram
A two-core control cable which does not need to be shielded is used for
the exchange of information and transmission of the digital commands. It is
not necessary to take the polarity into account. The control cable must not
have any SELV characteristics (safety extra-low voltage). The two unrequired
cores of the five-core NYM 5x1.5 mm
2
mains cable can thus be used for
example as a DALI cable.
64
63
or
1
3
2
4
Ballast
Ballast
Ballast
Relay
Dimmer
Ballast
Controller
Scene module
Control device
Power source
