The Digital Illumination Interface Alliance (DiiA) has expanded the scope of the DALI-2 certification program to include tunable white color control. DiiA also recently added its D4i certification program. D4i brings standardization to intra-luminaire DALI, and extends the existing DALI-2 program by adding a specific set of new features that create new possibilities for DALI in the IoT world. D4i specifies power-supply requirements and smart-data capabilities.
Color Temperature Certification
DiiA has added the color temperature Tc method of color control as a feature for DALI-2 control gear such as LED drivers. Commonly referred to as "tunable white", Tc allows control of the correlated color temperature (CCT) along the black-body line, from warm white to cool white.
"DALI-2 certification for tunable white color control has important implications for well-being and productivity in buildings," says Paul Drosihn, DiiA General Manager. "For example, color temperature control at different times of the day, coupled with light intensity measurements and occupancy detection from DALI-2 sensors, results in comfortable and efficient lighting schemes."
The first DALI-2 tunable white LED drivers, from DiiA member eldoLED, are already listed in the online Product Database.
Tc is one of several methods to control the color output of light sources—known as color types— that are described in Part 209 of the IEC 62386 standard. DiiA created the rigorous DALI-2 test procedures that allow DiiA members to confirm that their products meet the requirements of Part 209 color type Tc. The test results are verified by DiiA as part of the DALI-2 certification process, building further confidence in multi-vendor interoperability of certified DALI-2 products.
DALI-2 certification of LED drivers has been available since mid-2017. All DALI-2 drivers have compulsory attributes such as a standardized dimming curve. Tunable white color control is now added to the list of optional features for LED drivers, which also includes the ability to store and report a rich set of luminaire, energy and diagnostics data (DiiA Parts 251-253 respectively).
The other main color types are RGBWAF (known as "RGB color control") and xy-coordinate (known as "xy color control"). DiiA is developing DALI-2 tests for these color types so they can be included in the DALI-2 certification program at a later date.
D4i Certification for Connected Luminaires
By specifying power-supply requirements and smart-data capabilities, D4i enables intelligent, connected, future-proofed LED luminaires. Intra-luminaire DALI refers to a small DALI network inside an individual luminaire. D4i specifications ensure that power is available for control devices—such as sensors or wireless communication devices—that are attached to or integrated into the luminaire. D4i-certified LED drivers have an integrated DALI bus power supply, providing power to the DALI bus and to some control devices.
In addition, D4i for outdoor luminaires includes auxiliary 24V power supplies for devices with higher power requirements, such as city-wide transceivers.
D4i also enables intelligent luminaires by standardizing the storage and reporting of data relating to the driver, light source and luminaire. The bi-directional nature of DALI enables such data to be communicated with the lighting-control network. Data stored within the driver can be used for enhanced asset tracking, as well as performance monitoring, diagnostics and energy metering.
