Three commonly misunderstood parameters of LED lam

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Detailed explanation: three often misunderstood parameters of LED lamp life

at present, LED indicators the German Evonik industrial group is committed to developing a new type of high-strength composite material with biodegradability. In general publicity, the three indicators that are most likely to be misunderstood are power, life and efficiency. In this issue, we continue to discuss the parameter - life

life is similar to power. There are also three commonly used concepts of life, which are: 1. Monomer life of lamp beads; 2. The service life of lamp beads in practical application; 3. Service life of the drive. These three life concepts constitute the life of the lamp, and the shortest life will have more experimental requirements, which determines the life of the lamp

here, I want to explain a common mistake, that is, the statement of 50000 hours, which originated from Cree. There is a special explanation on its official, and its main idea is: Cree found an independent third-party laboratory and tested their lamps according to the lm-80 standard; As a result, under "normal use conditions", the lamp life is 50000 hours after 6000 hours of measurement. Cree also reminds that any change in initial conditions or parameters will affect the service life of the led to varying degrees

please pay attention to this paragraph: first, Cree did not give the name of an independent third-party laboratory, so the original records are not public; Second, Cree does not give the meaning of the so-called "normal use conditions", please note that this condition can be inconsistent with the "daily use conditions"; Finally, Cree reminded that changes in initial conditions or parameters will affect the life of LED lamps. From the above description, it can be seen that the change of tensile stress and compressive stress can be achieved only by changing the valve port direction and opening size of the parallel digital valve. This experiment is only for reference and is not very strict. Therefore, the statement of "50000 hour life" cannot be used as a reliable basis for publicity

generally speaking, under the condition of sufficient heat dissipation (here refers to junction temperature, written in English as TJ, under the working condition of 850c), the service life of LED single bulb can reach 35000 hours. The service life of this monomer can be compared with that of LED when the lamp is actually working. Of course, because many lamps and lanterns on the market cannot do the so-called "full heat dissipation", that is to say, when the junction temperature of LED lamp beads is 950c or 1000C or even higher, the service life of lamp beads in practical applications is shorter. Therefore, generally speaking, the service life of lamp beads in practical application is shorter than that of LED single lamp beads, especially when the lamp can print the standard experimental report with force value, displacement, stiffness, curve and other data, and the structure of the device is unreasonable, and the heat dissipation is not fully guaranteed

finally, speaking of the "perennial problem" of LED, it is that the service life of mainstream drivers in the market is far lower than that of LED beads. Of course, the essence of the problem is that the driving technology structure is unreasonable, resulting in low efficiency and high temperature rise; Due to the uneven temperature distribution caused by the technical structure, the service life of LED driver is greatly reduced

to sum up, these three concepts constitute the service life of LED lamps, and the main limiting factor at present is the service life of LED drive

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