The relationship between the working temperature and temperature rise and life of LED lamps
Generally, the low temperature working temperature of LED lamps is designed at -4℉ — -40℉, which can adapt to the requirements of most areas, and the summer temperature in the equatorial region may reach 122℉ or higher, and the lamp design must be 32 ℉—122℉ working environment can work normally.
The process requirements and component selection of LED products are different for different operating temperatures. Components in cold and low areas must choose low-temperature-resistant electronic components, and in high-temperature areas, high-temperature-resistant electronic components must be selected. Different temperatures. The production process and aging conditions of LED lamps in the area are different.
What is temperature rise?
The allowable temperature rise when the lamp is working is also a marking method to measure the heat dissipation capacity of the radiator. We know that incandescent lamps and gas discharge lamps (including fluorescent lamps, high pressure sodium lamps, metal halide lamps) generally do not require special heat sinks. Heat dissipation, only LED solid-state lighting needs a special radiator to dissipate heat, which is also the special feature of LED lighting.
The LED lighting chip emits light when it is working, and its light does not contain ultraviolet and infrared, so its light cannot take away heat; therefore, the temperature of the chip will rise when it is working. In order to ensure that the temperature does not rise too high when the chip is working, it is necessary to install a heat sink for the LED.
The temperature on the LED lamp radiator = ambient temperature + lamp temperature rise
For example: the manual of a high-end LED lamp gives its temperature rise ≦59℉. When the ambient temperature is 99℉, what is the temperature of the aluminum alloy radiator of the LED lamp? How many hours can the lamp's life span?
How long is the life of this lamp? The life of the lamp is closely related to the chip junction temperature. To know the PN junction temperature, you must know the integrated thermal resistance from the chip to the radiator. Generally, there are four thermal resistances from the chip to the aluminum radiator. If it is the same as the chip thermal resistance 39℉/W, the total of the 4 thermal resistances is 61℉/W. From its temperature and life curve, it can be known that the lamp has a life of nearly 90,000 hours.
