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Led disclaimer, Led life, Led binning – ILUMINARC Ilumipod™ Inground Tri-12 IP User Manual

Page 22: Color rendering index (cri)

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Technical Information

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Ilumipod Inground Tri-12 IP Optic WW User Manual Rev. 3

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 product 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
product to product. 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 U.S. 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 correlated color temperature.

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