LED lamp life and the actual discrepancy study confirmed that frequent switching will shorten

American Rensselaer Lighting Research Center (LRC) on the reliability of LED system have made a special study, research shows that some LED products on the market in some applications and product specifications of the content out there. In this study, the test center of three types of LED system to buy from the market, including LED A, LED MR16 lamp lamp and LED downlight, tested a total of 277 kinds of LED products. So, how to test results of Type A LED LED MR16 lamp, lamp and LED downlight?

Type A LED lamp

In the test, the Type A LED lights are fatal problems (product not luminescence) and parameters of fault. Contrary to the general view, the on / off switch can shorten the life of LED system. On / off switch will accelerate the fatal fault, the reason is not matching coefficient to the system caused by thermal stress caused by temperature change between the power cycle and the adjacent parts of thermal expansion. This leads to failure of materials such as LED interface, connected with the electronic board welding parts and / or drive parts. The results please see below.

The black line represents the fault period in the incremental time average temperature, the red line represents the L70 fault time at maximum operating temperature.

At the same time, the maximum working temperature will affect the rate of lumen and parameters of failure time, because the optical transmittance of adhesive material to keep the phosphor particles in LED packaging reduction. This fault in higher temperature and faster. In addition, high temperature will degrade in the drive element, affect the driver output current through LED, resulting in lumen attenuation, resulting in fault parameters. According to the analysis of failure samples, most failures are due to solder failure between the LED and the electronic board, a small part is due to actuator failure. For the Type A lamp test, critical failure time ratio short fault time.

Rensselaer Polytechnic Institute lighting research center data show that Type A LED for three hours every day if you use the lamp, it can be expected to last nearly nine years; for non IC (insulation contact) embedded downlight, if you use two hours a day, it can only be used for two years. All of these predictions than the rated life of LED products (products that use three hours a day, you can use more than 22 years) is much shorter.

LED MR16 lamp and LED downlight

The testing of the LED MR16 lamp, because the driver, almost all the lights are failure. Similar to the Type A LED lights, fatal fault (product cannot luminescence) longer than the short time fault parameters. However, when the LED lamp test during the test, only observed fault parameters.

It is worth noting that the feedback control circuit to detect the temperature of the LED LED system, let the device driver, the temperature does not exceed some lead to system failure. This system gives a lower light output at higher temperatures, this is to reduce system failure. In this case, the fault parameters (i.e. reduce light output) may be the only fault mode of existence.

There may be other systems using feedback control to change the LED current to maintain constant light output. In this case, the fault factors may need to consider increasing the power and non lumen depreciation. Certainly, the market most of the LED lighting system without using feedback control, because these features tend to raise prices. (compiled: LEDinside James)

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