Lighting can change the energy of a space and impact significantly on the productivity, feelings and well-being of the building’s occupants. It is a fast-evolving element within building design. Technology changes led by the rise of LED as a source are reshaping the landscape of lighting for architects and designers, and helping the drive towards more energy efficient, more versatile and lower cost lighting solutions for buildings.
Key to unlocking the potential of any lighting scheme is the control system deployed to manage it. By using an effective lighting control system, spaces can be created with multiple uses and properties. Automated dimming and colour control can be used to change the mood of a room and the dynamics of a zone or group of zones according to purpose, time of day, natural daylight, occupancy or other factors. Such controls are also capable of significantly reducing the lighting system’s energy consumption.
At the heart of lighting control thinking and practice is DALI. First drafted as a standard in 2000, DALI is a data protocol and transport mechanism that was jointly developed and specified by several manufacturers of lighting equipment.
DALI lamp fixtures are intelligent, 100% dimmable and can all be controlled, monitored and maintained using this two wire global IEC 62386 open standards communication protocol. A wide variety of fixtures are manufactured globally by manufacturers in line with DALI, including LED, fluorescent, HID, halogen, incandescent and emergency lighting, low voltage transformers, PE cells, motion detectors, wall switches and gateways to other protocols.
Up to 64 individually addressed DALI light fixtures may be connected on a single and simple two wire network to be communicated with individually, collectively or in groups. These DALI fixtures can then be instructed, by sending commands along the two wire network, to turn ON, OFF, Dim Up, Dim down. Additional operational status information is available from each DALI fixture, confirming its ability to operate effectively or to confirm a fault condition.
The key thinking behind the DALI standard was interoperability. The common platform of DALI enables equipment from different manufacturers to be connected together, giving designers a ‘best of breed’ competitive choice in performance and style of lighting solution for their particular building. This gives specifiers considerable flexibility where cost per square metre, functionality and form factor can often be determining factors on equipment selection.
Already part published and set to be completed by the end of 2015, DALI 2 is a new version of the DALI standard which is designed to fill gaps in the original standard.
It will pave the way for the future by bringing in standardisation of Control Devices for the first time, and increasing the scope of application up to building automation.
For the architect, the new additions to DALI offer added support for colour control, covering both RGB and colour temperature. This increased colour control gives architects many more options in how they can control the warmth of the light in each room of a building using DALI fixtures.
The new updates also deliver better reporting of important information, such as energy usage and LED temperatures, a key factor affecting the lifetime of the LED. This is important to the overall design of a building and it allows for the creation of a more sustainable and long-term energy saving solution.
Another great benefit of DALI 2 is that it will allow for an additional 64 addresses, specifically for control interfaces, such as keypads and sensors. Users can now have up to 128 addresses on a single DALI network, which means less equipment and fewer products will be needed to create a larger DALI based lighting system. Not only does this reduce overall complexity but it will also provide programming flexibility and scheme adaptability over the lifetime of an installation, since the designer will not be tied to a system configuration dictated by the cabling infrastructure. This makes a system much more competitive as it reduces cost and improves return on investment.
A new Logo Licensing Process is being introduced alongside the new DALI 2 standard. This will formalise the product testing procedure and will lead to the creation of a list of compliant products in the searchable DALI database. The DALI trademark logo, together with the DALI compliance mark, is needed for compliance with DALI testing according to version ≥2.0 of the standard. This allows architects and designers to be secure in the knowledge that the products they specify will be fully compliant and work seamlessly with each other.
DALI 2 gives specifiers greater freedom and in lighting system design and control. The new standard will enable the configuration of lighting groups and presets to match the lighting to the use of space whilst at the same time offering integrated energy management functions. In addition, as an open system, DALI enables interoperability among many vendor products and standardised performance across manufacturers. With DALI’s new control and colour features, architects will be able to design better-looking, more efficient and responsive spaces.
More information is available at www.dali-ag.org