DALI Features DALI is full of useful and handy features which you can choose to use. ( This list is only a sample of the many DALI can provide) Digital Transmission DALI employs a digital transmission signal which makes it less prone to the transmission errors that typically effect analogue control signals. Unlike the older 1-10v analogue systems or the propriety DSI systems the DALI signal allows for Bi-Directional Communication which creates the ability to obtain functionality results directly from the DALI device. A simple diagram of a DALI network can be viewed here. Individual control Each DALI device has its own address which enables individual communication and control over a single DALI bus. This means that you can wire up to 64 DALI devices together and control them separately, whereas traditionally you would need to wire each device separately. Individual control provides the means to gain the maximum power savings and comfort. A diagram of DALI addresses can be viewed here. Feedback and control Individual control is exploited through a broad range of queries/commands. These include: - Turn on/off
- Dim up/down
- Lamp status (faulty, working, running hours)
- Dali Device Status
- Set features such as Power_on_level and System_Failure_level
The feedback from the device provides the perfect method for minimizing maintenance costs of the building while ensuring a safe working environment
Scenes and Groups As well as individual control DALI also supports two new concepts called Scenes and Groups. These concepts allow for the control of several different DALI devices with the use of one command. - Scenes:
Hint: Think of a scene as a setting; for example in a meeting room you may want the lighting to have different settings for different tasks (meeting, presentation, video presentation, lunch) There are 16 different scenes available for each DALI bus. When a scene command is sent across the DALI bus every DALI device receives the command and checks its memory. If it has a stored action the DALI device will perform the action, otherwise it will ignore the command. A diagram showing a scene can be viewed here. - Groups:
Groups allow multiple DALI Devices on the same Bus to be Grouped together this allows the devices to perform an action together. Hint:you can group Devices together into Room or areas to perform functions easier Each DALI device can be assigned membership to a group or multiple groups. This grouping allows commands to be sent out in groups with all members of the group reacting to one individual group command. If a device is not part of the group it will be ignored. A diagram showing a group can be viewed here.
NOTE:Traditional systems of lighting control don't always understand the application of groups and scenes, many systems originally used each DALI device as an individual lighting channel, which is a slow and messy method. If you have ever seen a room of lights turn on one by one, then this is most likely a system which uses channel control and not group or scene control as was designed into DALI. Some system providers will also say that DALI's communication speed is slow, this is normally because they have taken the channel approach to DALI. For example, if we compared a channel based system to a proper DALI control of a group of 20 light fittings, the channel based system would have to issue 20 individual commands, where are the correct method would use one group command, achieving the goal 20x faster. It is recommend when selecting a DALI control system, that you ensure you decide on one which fully supports DALI groups and scenes ( you would be amazed how many system providers still don't use the correct method, and blame their poor implementation on DALI.)
Functionality and Flexibility Because of the localized intelligence within each DALI device, it becomes possible to turn the DALI device on or off directly from the DALI control system rather than using a mains switch. This brings greater functionally and allows for flexibility and change after installation. Moreover, changes can be made to scenes and functions through simple programming without the addition of any new hardware Adjustable features DALI devices have a number of features which can be changed to adjust the operation of the device. Some features are listed in the following table. - Power on Level: 1-100%
- System Fail Level: 0-100%
- Minimum Level: Physical Min Level -100%
- Maximum Level: Min Level - 100%
- Fade Rate: 1-15
- Fade Time: 1-15
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