Speakers
Description
Colour tunable and dimmable LED lamps and LED luminaires are used increasingly in both domestic and professional lighting sector. The documentation of energy and light quality performance are often very limited for only for a single setting of multiple possible settings. Fifteen LED lamps and eight LED luminaires that are dimmable and tuneable white have been selected for demonstration of the variations in these parameters and possible errors in lighting design simulations. These have been tested in over twenty modes of operation including dimming from 100% to 25%, and correlated colour temperature (CCT) settings from 2200K to 6500K. The inherent standby power of these colour tuneable devices is measured, and the overall efficacy is evaluated in normal usage situations. In average for all tested LED lamps and
luminaires 49% and 33% of the energy consumption is used in standby mode for 1h and 2h on time pr. day, respectively. The extensive set of test results show that there can be very large variations in e.g. the luminous flux, luminous efficacy and stroboscopic visibility measure (SVM), while others are very consistent over the modes of operation. The luminous flux shows variations of down to 22% of the maximum and rated value, and these lowest values occurs at the lowest CCT. The best performing has over 90% at all CCT settings. For the luminous efficacy most test results show a maximum value at 4000K or at the maximum CCT, and variations down to 20-50% of the maximum efficacy. The SVM is shown to increase to values over 1 and up to 2.4 at low dimming levels or low light output, demonstrating that stroboscopic effect will be visible for the majority of people and hence a problem in such settings. This is seen for approx. half the tested while the others have SVM < 0.4 for all settings and will not be visible over all settings. These results demonstrate the need for testing over the possible modes of operation to be able to correctly design and simulate a lighting installation using dimmable and colour tunable LED lamps and luminaires. The needed new dataformats and adoption of these from test laboratories to lighting software, in order for lighting designers and energy engineers to be able to make use of the extensive test results, are discussed.
