Setting the scene with DALI

This season, Timeguard is adding its trusted brand name to the field with the launch of a line- up of DALI-compatible PIR controllers with controller, power supply and remote IR controllers. Now, you have everything you need to get started from a brand you know you can trust. After all, as installers you are used to providing home-owners and businesses with zoned lighting and scene setting – why not take it to the next level?

There are clearly cases and places where ordinary lighting is fine. If the application is simple and doesn’t require daylight harvesting, dimming, occupancy control or individual user control, DALI isn’t the answer. When you do want to add something extra, then it is well worth thinking about.

A DALI system just needs a DALI bus for communication between different points on the system such as the controller and a PIR. So, an extra pair of cables between devices and control points of the system is needed. Standard 2-core, minimum 1.5mm2 is sufficient. A DALI loop can contain up to 64 devices, typically LED drivers or PIRs, with multiple loops linked for larger projects.

The Digital Addressable Lighting Interface (DALI) is a standard that enables different devices on a system to talk to each other – they don’t even need to come from the same manufacturer. It’s an international standard, specifically created for lighting, for a two-way communication system that gives easy control and versatility. In a traditional system, control signals are one-way. In a DALI system, signal traffic is two-way, meaning LEDs can be commanded to perform requested actions, such as switch ON/OFF or DIM, but they can also be asked to provide information. The LED driver or switch can provide, for instance, information about intensity and energy consumption or it can simply verify that it is working.

A DALI network consists of a controller, a power supply (which may be built into the controller) and one or more slave devices (eg ballasts, drivers, dimmers and PIR detectors) that have DALI interfaces. The controller can address devices individually or by multicast. Each device can be assigned to up to/any of 16 groups and can store up to 16 scenes that can be controlled by a single command. DALI sends messages around and just like computer networks, the ballast with the right address picks up the message and follows the instruction. It might be ‘turn all the lights in the corridor on’, or it could be ‘switch to the theatre lighting scene in the conference room’.

Now that you know the basics, the decision may be a little more straightforward. Do you want to light several rooms that require different lighting options depending on the time of day, usage etc? If so, think about DALI control with the new Timeguard range.