Factors affecting the quality and decay of LED solar light
First, choose what kind of LED solar lamps.
This is very important, the quality of LED solar lamps can be said to be a very important factor. To give some examples, the same 14mil white light segment chip is represented by LED solar lamps encapsulated with ordinary epoxy resin primer and white light adhesive and encapsulating glue. A single light in a 30-degree environment, one thousand hours later, The attenuation data is the luminous maintenance rate of 70%; if it is encapsulated with D-type low-failure glue, the light attenuation is 45% per thousand hours under the same ageing environment; if it is encapsulated with the C-type low-failure glue, the same Hourly light decay is 12%; if Class B low-failure glue is encapsulated, under the same ageing environment, the thousand-hour light decay is 3%; if Class A low-failure glue, under the same ageing environment, the thousand-hour light decay is 6 %.
Second, the working ambient temperature of LED solar lamps.
According to the data of a single LED solar lamp when it is ageing if only one LED solar lamp works, and the ambient temperature is at 30 degrees, then the temperature of the bracket when the single LED white lamp works will not be More than 45 degrees. At this time, the life of this LED will be ideal.
If there are 100 LED solar lamps working at the same time, and the interval between them is only 11.4mm, then the temperature of the bracket of the LED solar lamps around the pile may not exceed 45 degrees, but Those LED solar lamps have a high temperature that may reach 65 degrees. At this time, the LED lamp beads are a test. Then, the LED solar lamps that gather in the middle will theoretically have a faster light decay, while the LED solar lamps around the pile will have a slower light decay.
Anyway, everyone should know that LED is afraid of heat. The higher the temperature, the shorter the LED life, the lower the temperature, the longer the LED life. The ideal operating temperature of the LED is of course between minus 5 and zero degrees. But this is impossible.
Therefore, after we understand the ideal working parameters of LED lamp beads, we try our best to enhance the functions of heat conduction and heat dissipation when designing lamps. Anyway, the lower the temperature, the longer the LED life.
Third, the working electrical parameters of LED lamp beads are designed.
According to the experimental results, the lower the driving current of the LED solar lamp, the smaller the heat emitted, of course, the lower the brightness. According to the survey, the design of LED solar lighting circuit, the driving current of LED is generally only 5-10mA; products with a large number of lamp beads, such as reaching more than 500, or more, the driving current is generally only 10-15mA However, the driving current of general LED application lighting is only 15-18mA, and few people design the current above 20mA.
The experimental results also show that under the driving current of 14mA, and the cover is impervious to the air, the temperature of the air inside reaches 71 degrees, the low-decay product has zero light attenuation in 1000 hours, and 3% in 2000 hours. This shows that the use of such low-decay LED solar lamps has reached its maximum in such an environment, and the greatest damage is to it.
Because the ageing board for ageing has no heat dissipation function, the heat generated by the LED during operation cannot be conducted to the outside. This is proved experimentally. The air temperature in the ageing board has reached a high temperature of 101 degrees, and the surface temperature of the cover on the ageing board is only 53 degrees, which is a difference of dozens of degrees. This shows that the designed plastic cover does not have the function of heat conduction and heat dissipation. However, in general, lamp design, the function of heat conduction and heat dissipation is considered. Therefore, in summary, the design of the working electrical parameters of the LED lamp bead should be based on the actual situation.
If the heat conduction and heat dissipation function of the lamp is very good, it does not matter if the driving current of the LED solar lamp is increased a little, because the LED lamp beads work The heat can be exported to the outside instantly, without damaging the LED, which is the best care for the LED. On the contrary, if the heat conduction and heat dissipation function of the lamp is so-so, it is better to design the circuit to be smaller and let it release less heat.