Friend LED Lighting Co., Ltd.
What is the Lifespan of LED's?

What is the Lifespan of LED's?

Times:2010-6-24 Clik:1059 Size:S M L Back

Swallow 2010-6-24

LED Lifespan

The “life” of an LED is generally accepted to be when the luminous output drops to 70% of its original intensity. A power LED industry group, Alliance for Solid-State Illumination Systems and Technologies (ASSIST) conducted tests in a commercial lighting environment that showed people generally did not notice a gradually diminishing LED light output until it had dropped by 30% of its original brightness. This value is known as L70.

Most quality LED’s available today offer a L70 of 50,000 to 60,000 hours.

So, if an LED light is used on average for 2.5 to 3 hours per day, then it will reach L70 in around 50 years.


LED lifespan and heat

LED’s offer a fantastic reliable light source, but only with a well designed light fitting.

The greatest LED killer is heat.

Consider that the part of the LED that emits light can be a little over one square mm. Relative to its size, this tiny chip produces a lot of heat, which must be drawn away as rapidly as possible.

Have you ever wondered why, with high performance fittings, such a big heat sink is needed if LED’s are supposed to run so cool? Without such a big heat sink we could not offer such a long anticipated life.

Every added degree of operating temperature above the rated threshold of the tiny LED chip inside the fitting results in degradation of the L rating mentioned above. This is why you will see the best quality downlight fittings with seemingly oversized aluminum heat sinks. However, over time, LED efficiencies will continue to improve with a resulting decrease in the minimum heat sink size.


LED lifespan and power

LED’s must use a special power source. It is not simply a regulated voltage power supply.

LED’s operate by precise control of current to the semiconductor.

For the majority of LED downlights this is accomplished by the use of a precision current-regulated electronic driver, especially matched to the power rating of the LED fitting. Over supply of current to the semiconductor results in degradation of LED life.

This is why our FriendLED kits are always supplied with a matched driver. There can be no confusion.

Substitution can result in instant destruction of the semiconductor or longer term accelerated degradation of the luminous output.

Copyright © 2013 Friend LED Lighting Co., Ltd. All Rights Reserved
Email: Skype: friendled MSN: