Choosing DALI Lighting Controls



Calon have been featured in the October Issue of Energy in Buildings & Industry magazine, discussing what should be considered when choosing DALI lighting controls. Read the article below or subscribe to receive a monthly copy of EiBI magazine by clicking here.



DALI Lighting controls are the norm in commercial, education and even residential applications. For retrofits in commercial properties, a good DALI control solution coupled with modern LED light fittings can reduce energy consumption by over 90%, while offering improved working conditions and a massively reduced maintenance requirement. 


DALI is attractive because of simplified installation requirements compared to other control solutions, as well as the wide availability of DALI light fittings. The real benefit, however, is that DALI provides two-way communication, allowing a DALI controller to read back status information from each lamp, including details of any faults. This makes DALI the solution of choice where lighting controls will form part of a building management system or where cost-effective virtual metering is required. So what should you look for when choosing DALI lighting controls? 

Let’s consider three aspects: features, installation & setup, and maintainability.


Features:

DALI controls can be either broadcast or addressable. As its name implies, a DALI broadcast is sent to all lamps, and if all you want to do is control lights in a single room, a broadcast solution may suffice. As soon as you need to control more than one zone on the same DALI bus, an addressable system is required. Bear in mind that the valuable feedback and status information is only available when the lamps have been individually addressed. Many lighting controls marketed as DALI are in fact only broadcast DALI, so check that what’s being offered will meet your requirements.

As a minimum, a good DALI solution should offer both occupancy-based and constant-light (daylight harvesting) control capabilities. With a combination of these two functions, correctly set up, it’s possible to achieve energy savings of 98% of the theoretical maximum, i.e. as good as it gets. 
Think about other features you may need: corridor linking ensures that while the lights in a room remain on, the exit route via the corridor will be lit also, at a lower level. Scene recall in a meeting room or presentation area allows different lighting moods to be created for presentations or various formats of event. A good DALI lighting control solution should also be able to offer an emergency light testing capability that meets your needs, is easy to use and conforms fully with current regulations. 

In larger buildings, there may be requirements for controls to act between DALI channels or between controllers – for example, a sensor on the stairs at second floor level may need to trigger lighting further up the stairwell, served by another controller. Can your chosen solution accommodate this?


Installation and Setup:

Installation schemes using pluggable, prefabricated cable assemblies may cost a bit more but will generally result in a much faster installation, with fewer snags.

While a larger system will need a commissioning engineer, a good entry-level solution should allow the installer to handle the setup themselves. Calon’s SmartSensor™, for example, provides a high-performance solution for single-room and smaller systems where the sensor itself takes care of the addressing and grouping of an entire DALI channel. This means that a smaller system can be quickly set up and commissioned by an electrical installer using only a simple handheld remote control.

For larger systems, a web-based or app-based setup workflow can greatly simplify the commissioning process, especially when combined with the facility to pre-engineer the settings for a unit and download on-site.


Maintainability:

Lamp ballasts and drivers can fail over time. A good DALI lighting system should offer a self-healing function, where a replacement device is automatically addressed and configured to match the settings of the failed device it’s replacing. That way, an electrician can undertake replacement work, without needing a specialist engineer.

A good lighting control system will make changes easy, too – for example, adding a partition within an office - through the use of a simple web interface or graphical software that makes it easy to add or remove control zones without needing to be a DALI specialist. Calon’s SmartBridge™ range and the L-DALI range from Loytec are good examples of controllers that provide a simple web interface for maintenance and setup.


There will be times when your system may need some specialist attention. Can the system be remote-monitored and managed via the internet?   Can it be linked to a BMS? Look for a system that offers a simple web interface as well as supporting one or more popular BMS protocols such as BACnet, LonWorks or Web Services.


For further information, please do not hesitate to contact us.