FAQ Section:

LED FAQ:

1. What is an LED?

2. Why is the life span of an LED measured as lumen depreciation?

3. How long is 100,000 hours?

Q: What is an LED?

A: LED is the common abbreviation for a light-emitting diode. Each individual LED consists of a semiconductor diode that emits light when a voltage is applied to it. The electronics industry has used LED technology for several decades as indicator lights for various electronic devices. In more recent years, LED technology has progressed to the point where it is viable for general lighting applications.

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Q: Why is the life span of an LED measured as lumen depreciation?

A: The life span of an LED is vastly longer than that of incandescent, fluorescent or HID lamp sources, generally lasting 50,000 hours or longer.

Although the LED never really burns out, product life span is measured by lumen depreciation. The Illuminating Engineering Society's (IES) current standard for calculating the life of an LED as the point at which the LED reaches 30 percent lumen depreciation.

Remember, a 100,000-hour rating is not equivalent to lamp life rating. LED life is rated where it has reached 30 percent lumen depreciation. At 100,000 hours an LED would still be operating, but at a decreased lumen output.

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Q: How long is 100,000 hours?

A: For this many hours of operation a day, 100,000 hours is:
    24 hours a day = 11.4 years
    18 hours a day = 14.8 years
    12 hours a day = 22.8 years
      8 hours a day = 34.2 years

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