Led disclaimer, Led life, Led binning – ILUMINARC Ilumipod™ 42 IP User Manual
Page 30: Color rendering index (cri), Technical information
Technical Information
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Ilumipod 42 IP Optic Series User Manual Rev. 6
LED Disclaimer
LED Life
ILUMINARC
®
rates LED lifetime based on lumen depreciation of 70% of the original
output, with data provided by the manufacturer of the LED. Data from the manufacturer of
the LED are not independently verified or measured by ILUMINARC
®
. When the fixture is
operating in optimal environmental conditions, the LED lifetime is rated to be 50,000 to
70,000 hours by the LED manufacturer.
LED Binning
LED manufacturers sort LEDs into “bins”, based on variances in color, output intensity and
the frequency at which the semiconductor operates. ILUMINARC
®
strives to hold its LED
manufacturers to the highest standards of binning to optimize consistency in output from
fixture to fixture. However, the availability of a single bin cannot be guaranteed. With that
in mind, ILUMINARC
®
has developed a rigorous control system to seek the best
achievable consistency in color and output.
Color Rendering Index (CRI)
CRI is an industry standard method to compare properties of different types of light sources.
There are known limitations and inconsistencies related to CRI. Results may vary depending
on the environmental factors involved. For this reason, the US Department of Energy (DOE)
states that CRI should be considered as one point of reference among others in evaluating
white LED products and systems.
The following is an excerpt of recommendations from the DOE:
1. Identify the visual tasks to be performed under the light source. If color fidelity
under different light sources is critically important (for example, in a space where
color or fabric comparisons are made under both daylight and electric lighting),
CRI values may be a useful metric for rating LED products.
2. CRI may be compared only for light sources of equal CCT. This applies to all light
sources, not only to LEDs. Also, differences in CRI values of less than five points
are not significant, e.g., light sources with 80 and 84 CRI are essentially the same.
3. If color appearance is more important than color fidelity, do not exclude white light
LEDs solely on the basis of relatively low CRI values. Some LED products with
CRIs as low as 25 still produce visually pleasing white light.
4. Evaluate LED systems in person and, if possible, on-site when color fidelity or
color appearance are important issues.
Source: DOE publication: PNNL-SA-56891, January 2008