A DALI LED bollard works in the same way as any other DALI lighting solution. DALI is a bus, pair of wires that carry digital control signals from input devices to application control. The process starts with a bus power supply unit (PSU), required to maintain the bus voltage at the required level. The lighting fittings should have a DALI driver and it receives commands directly from the DALI bus and can respond accordingly. The input devices, such as switches or sensors, will then communicate with the application controller using 24-bit data frames.
At this stage, the input device can include instances. Instances are multiple devices, all inserted in the same input devices. For example, the same input device can include a PIR LED bollard and a light-level detector. Lastly, the application controller device works by receiving 24-bit messages from the sensors and issuing 16-bit commands to the control gear. This application controller can manage the data traffic and check for errors and report on statuses.