Why is the operating temperature critical to the life of the LED fixture?

The failure rate for most electronic components will double for every 10 °C increase in temperature. This is true for both the LEDs and of the power supply. LED manufacturers have demonstrated that at an LED junction temperature of 135 °C one can expect to get 50,000 hours of operation before the light output will have degraded by approximately 30%. The above “10 °C” rule suggests that if one operates the LED at 85 °C will extend the 30% light-degradation interval out to about 16 x 50,000 hours, or about 800,000 hours. As the LED manufacturers’ accelerated life tests continue, one can expect this result to be verified by actual test data.

ALLED’s light fixtures are designed to take advantage of this fundamental, temperature-related characteristic of electronic components. For a typical ALLED streetlight design, at an ambient temperature of 20 °C, the LED junction temperature is approximately 85 °C. It follows therefore that one can project that the fixtures will see only a 1-to-3 percent degradation over a 50,000 hour period compared to upwards of 30 percent by other LED lighting companies.