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-15°C
+25°C
+80°C
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PERFORMANCE IN LIGHTING has been very successfully using LEDs
in its luminaires for some years now. Reason enough to dedicate a
chapter exclusively to this illuminant technology. PERFORMANCE
IN LIGHTING installs LEDs only from well-known and respected LED
manufacturers. At this point, however, we would like to focus less on
LED manufacturers, but rather take a look at the fundamentals of LED
technology. In addition to many other positive characteristics that
LEDs display in PERFORMANCE IN LIGHTING luminaires, LEDs also have
a few general characteristics:
With conventional light sources, light and heat are radiated in all
directions. In conjunction with a refector, this can lead to high
temperatures on the irradiated surface. LEDs emit light, but no UV or IR
radiation in the direction of the lit surface. Upwards of a total output of
approx. 40 W in an LED point module, active cooling is necessary. This
cooling is done by a fan.
Linear LED modules and panel LED modules can be cooled passively
even at higher system outputs. Increasing temperature also alters other
relevant parameters of the LED. Thus the luminous fux of the LED
decreases with increasing temperature.
BENEFITS:
• No thermal stress due to IR radiation
➡ Food sector, people
• No UV radiation
➡ Museums, leather & fashion shops
• Luminaires become lukewarm at most
➡ Adjustable in operation
• Immediate restart at full power possible at any time
➡ Power failure, motion sensors
• Maintenance-free
• Mercury-free and thus simple to dispose of
• Impervious to vibration
• Steplessly dimmable without loss of light quality
• Flicker-free light
For a better understanding of LEDs, a few basics are explained in more
detail below:
White Light Generation
White LEDs as manufactured today are based on a blue LED overlaid
with a yellow-emitting luminescent material. The two complementary
colours in the blue and yellow range then produce the LED’s white
light. The three basic colours blue, red and green also produce white
when mixed, although with lower efciency.
The result of this is that the luminous fux does not increase linearly
with the operating current, since with a higher operating current, the
LED also reaches a higher temperature and a lower service life must
therefore be expected.
Thermal Behaviour
Although the LED is a very efcient illuminant, nevertheless approx.
30% of its performance is transformed into heat.
This heat however arises almost exclusively on the LED mounting
surface and is not emitted in the direction of the light.
Wavelength in nm
Relative intensity
Wavelength in nm
Wavelength in nm
Additive
colour mix
LED
Chip
LED
Chip
e.g.
white
Additive
colour mix
e.g.
white
Blue emission
Luminous particle dispersion
Yellow emission
Blue emission
Red emission
Blue emission
Green emission
Blue emission
Blue emission
LED Technology