Author: Cunhui Wei/ Technical Service Center
La color temperature is a quantity that measures the color that light contains. are the different light colors that produced when an absolute black object is heated to different temperatures. For example, in sunlight, the temperature is lower in the morning and evening hours, and the color temperature is warmer yellow. However, at noon, the temperature is higher, and the color temperature is cooler and whiter.
In the Figure 1 color temperature ratio is displayed from 1000K a 10000K. The lower the color temperature value, the redder the color; the higher the color temperature value, the bluer the color.
The lamps with a single color temperature, they don't fit well at different circumstances of life and work of people, because these needs vary according to the circumstances.
As we see in the Figure 2, for lighting hotel rooms, the lcool or neutral white light is preferable for read and communicate during the dayWhile warm light can ease the physical and mental fatigue, improving the quality of sleep at night.
Without a doubt, LED luminaires with adjustable color temperature are getting more and more popular in lighting environments residential, hotel, office and commercial because they offer an imore personalized lighting which satisfies all those needs at different time intervals.
As we see in the Figure 3, LED luminaires with adjustable color temperature and brightness, they use two sources of light output: color temperature cool (6500K) Y warm (2700K), each of which is relatively independent.
As shown in the ffigure 4, color temperature can be adjusted by changing the drive current of each light source. When the color temperature is specific, the brightness can be adapted by setting the driving current of the two light sources in the same ratio.
With the development and advancement in the lighting industry, the Digitally dimmable LED Drivers ensure color temperature and brightness settings do not interfere with each other. This design has replaced gradually the «constant voltage source + DC/DC dual output module» as a new driving method focused on create a smart, comfortable and human-centered lighting environment.
OLFER Electronics and MEAN WELL have launched a smart power supply; LCM-40TW compatible with DALI2 with tadjustable color temperature and brightness.
The LCM-40TW is LED drivers with 2 outputs for regulation of brightness and color temperature (Dynamic White – Tunable White). Works on dual channel constant current mode de 40wa interruptedDIP ptor which can be adjusted to DALI DT6 (led lighting control device) or DT8 (color temperature control device). Besides, offers current output selectable by means of a micro-switch (500 a 1050mA). This device allows users to vary the color temperature and brightness through a switch. A smart solution for lighting control.
Source: https://www.olfer.com/mean-well-led-driver-inteligente-dali-2-lcm40tw.html
