The DALI protocol limits the system to a maximum of sixty-four single units, a maximum of sixteen groups, and a maximum of sixteen scenes. Each of the sixty-four single units is assigned a short address, which is stored within the ballast. Each individual unit may also contain a group assignment number, lighting scene values, fading times, and emergency lighting levels. Short addresses may be programmed into the ballast by the manufacturer during production, or may be programmed by the designer during the installation process. Group addresses are typically assigned by software during installation, allowing for future changes in the group structure.
DALI has a free-form wiring structure, so the use of daisy-chained, linear, star, or mixed structure wiring connections are allowed, with the exception of ring-shaped connection structures. DALI sets a maximum distance of 300 meters between unit connections, and allows a maximum of a 2-volt drop across the connecting wires from the interface power supply to each unit. The DALI bus operates at a 1200 bps baud rate, so there is no need for special cables or wires.