LED Dimming Performance

What to look for in Dimming performance:


Flicker - In some instances there can be unacceptable flicker that is observable when the minimum Load requirement of the dimmer has not been met.


Smoothness - Smoothness is somewhat subjective, as it is a rating of the fixture’s reaction as can been observed during a long (20second) fade from full on to full off. Any perceptible flickering, jumps, or flashing can affect the assessment of dimming smoothness.


Dimming Linearity - An important consideration of dimming performance is perceived linearity in dimming performance between the user interface (“dimmer”) and the perceived lighting effect. Perfect linearity could be defined as equal (observed) dimming steps throughout the range. If the jump from 10% to 20% is observed as a larger dimming step than the jump from 90% to 100%, this would be one example of non-linearity. Each 10% interval in the range should produce an equal dimming step (one tenth of the perceived brightness at full on).


All Vantage InFusion - compatible line - voltage dimmers feature an ‘Adjust’ parameter designed to allow best fit toward achieving an ideal dimming curve. In the LED testing performed at Vantage, experimentation with ‘Adjust’ is performed to bring the curve as close as possible to a target “ideal”.


Unfortunately, not all LEDs react to dimming like an incandescent bulb does. Aside from the potential for incompatibility, resulting in noise, flicker, and the like, even a compatible LED will likely be limited in its performance when compared to the incandescent bulb. Most notably, LEDs typically exhibit an elevated low-end dimming range threshold, meaning you cannot dim it beyond some point that depends on the characteristics of the LED light source and its driver. A second concern with dimming LEDs is that one cannot necessarily predict their linearity. In other words, when the dimmer is set for 50%, where the expected light output perception would also be expected to be at 50%, it might be at 80%. Fortunately, Vantage provides features to remediate most of these issues.


The Power Profile – Through InFusion Design Center software, custom power profiles can be defined and assigned to individual lighting loads. By applying a power profile that matches the best-fit power profile as determined through testing, we eliminate low - end anomalies and maximize dimming linearity. In addition to the ‘Adjust’ parameter previously mentioned, the high and low ends of the dimming range can be set to optimize linearity as well as eliminate problems that might present themselves at the low end of the dimming range. These values are all determined during testing of particular LEDs, since these cannot be predicted without actual test, and the values reported in the test reports for implementation by the system programmer.


For a more comprehensive treatment of these technical issues, please refer to our LED Testing Guide.


Vantage offers a full range of products that are compatible with dimmable LED light sources. Our dimmers are unique in their ability to be configured, through our system design software, for optimal performance for the specific characteristics of a particular lighting product.