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Random Address The DALI standard uses a 3 byte Number to assign Random addresses to the device being addressed. This allows the software to find each of the dali devices on the DALI network and assign them their DALI address (Short address) When the DALI device is given a command to Randomize, the Device will randomly generate this random number. Although this number is large, the chance of two devices randomizing to the same random address number is very low, but could still occur ( remember each bus only has a maximum of 64 devices). The likelihood of this "doubling up" could be different from manufacture to manufacture and some earlier DALI devices seamed to show this occurrence more others, however today most manufactures have reduced this issue. However the double up of the random addresses could still happen every now and then, this is quite easily solved through the software addressing algorithm. Macolighting's software has inbuilt routines to deal and eliminate this issue during the addressing mode, information on this software can be found here: Maco Lighting CT What is the DALI Long Address? Some manufactures have renamed"Random address" to the word "Long Address" in an attempt to disguise or rewrite the use of the random address. The random addressing was designed to be used during the commissioning / addressing stage of the project. After this time the use of this feature was designed not to be used as the ballasts all contain a "short address" number (0-63). Some manufactures however have utilized the random address in a way which seams smart as they could restore a network if some untrained person makes a mistake, but realistically is making it harder for other parties ( outside the commissioning agents) to make changes to the DALI network. Basically they have made the assumption that the command "Randomize" would never be called again, and that the "random address" would remain unchanged for the life of the project. They then use and store the "Random Address" as the primary key for the ballast, and if they detect changes or refresh the installation or even add new devices, they would restore the stored address back into the device with the recorded Random address. This procedure causes a few problems for the customer or future contractors such as
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