led tube light fades relying on good cooling technology
25/10/2013 18:29
In the global led tube light market continues to expand on the occasion , in addition to Europe, America and China and other potential markets , and do not overlook a very explosive Indian market. Taiwan International Lighting Show just ended , exhibitors join the festivities , have exhibited a variety of the latest led tube light applications .
After two years of development, in 2010 , India expects that more than one billion U.S. dollars , breaking the 12% annual growth , the global LED market is quite promising emerging markets , mainly with the economic growth of the country's electricity driven great demand , subject to resource constraints, only advance carbon reduction LED application layout , or build more power plants is not enough .
India's demand for led tube light products mainly rely on imports , in 2004 India's imports amounted to 6,470 LED million U.S. dollars, in 2005 imports had increased to 7,123 million U.S. dollars, in 2006 LED imports reached U.S. $ 88.5 million , annual growth rate of more than 11.93 % to2007 India's economic growth is more rapid , LED amount of imports hit record highs .
Industry for heat from thermal conductivity and heat both sides have always discussed. For heat dissipation in the LED industry too much emphasis on additional heat conducting layer in front of the practice of general practice in the industry put forward different fundamental solution.
From the viewpoint of heat conduction , the traditional MCPCB bottom aluminum plate is simply redundant, the thermal conductivity between the copper foil usually hard texture plastic material , the temperature rises because of copper and aluminum sizing different coefficients of thermal plastic resulting intermediate increasing gap layer interface thermal resistance.
MCPCB thermal aluminum industry preferred substrate is an aluminum block from the bottom and the upper foil group , the middle filled thermal plastic (Adhesive) formed. Copper resistance 0.001cm2? K / W is close to 0 , the bottom thermal resistance of aluminum 0.08cm2? K / W, but the thermal plastic thermal resistance up to 1cm2? K / W, true to the MCPCB thermal resistance measured about 2 ~ 4cm2? K / W.
Taiwan's Ministry of Economic Affairs recently estimated that if the future Taiwan 2,300,000 lights can be changed to LED lights , 1 year can save 750 million kWh of electricity, as well as NT $ 1.5 billion in electricity, while reducing 517,000 tonnes carbon dioxide emissions.
We saw some interesting phenomena . That is exhibited in some large manufacturers lights, stage lights, outdoor wall lights found on the heat lamp light shell coated with a thick layer of black paint tradition , like the led tube light painting is the same as water pumps .
Interviews , we learned that manufacturers say that because it is used in the outdoors, to endure climate change, acid rain , and had sprayed paint protection. Why use black paint it ? The answer is actually more dirt , dirty comparison can not see.
Why use paint it ? Do not worry about the paint will form a thermal resistance caused by the led tube light failure ? The answer is , if anodized still have thermal protection , and exposed for a few months will fail , had to use paint protection , even if the light fades will also try to get through the engineering units of acceptance fine.
Unexpectedly, this external protective paint confused efforts row cooling module out of the heat and seal scattered back , resulting in improper cooling, a serious cause the LED epitaxial lumen.
Temperature is actually failure LED street light key issues , but why LED lights on the card in this link. LED street light power is greater than the household lamps , so the manufacturers in the cooling fins substrate , cooling fan design painstakingly , until fully assembled but also outside in the fixture and cooling modules plus paint protection against weather erosion.
When importing calculated heat flux , the heat flux q = Q ( total heat ) / A ( surface area ) = (T1-T2 temperature difference )? K ( thermal conductivity ) / l ( by length) of the LED constant heat flow q is a fixed constant, the thermal resistance (Rt) is divided by the length l of the thermal conductivity value of k , the shorter the length of heat conduction can effectively reduce the overall thermal resistance , and the total thermal resistance of the interface with the thermal resistance between , as well as interface interface thermal resistance between the accumulation and rising.
According to the present large-scale street acceptance , LED lamp life test : more than 1,000 hours of life testing, the amount of light attenuation is less than 3% ( dry of lighting ) ; 15,000 hours of life test , the light attenuation is lower than 8%. Pass specification , you'll get the acceptance of public works funds .
If the thermal resistance of the following formula into Rtotal = Rl-s + Rs + Rs-a, a total thermal resistance of the LED thermal resistance between the LED to the substrate , with the substrate resistance (Rs) coupled to the air side of the heat the substrate resistance (Rs-a) the sum of the three . Aluminum plate resistance Rs in general about 2 ~ 3cm2? K / W, the thermal resistance of the substrate to the air side of the heat- up Rs-a 400 ~ 3,000 cm2? K / W, instead of on the substrate side of the bottleneck .
After two years of development, in 2010 , India expects that more than one billion U.S. dollars , breaking the 12% annual growth , the global LED market is quite promising emerging markets , mainly with the economic growth of the country's electricity driven great demand , subject to resource constraints, only advance carbon reduction LED application layout , or build more power plants is not enough .
India's demand for led tube light products mainly rely on imports , in 2004 India's imports amounted to 6,470 LED million U.S. dollars, in 2005 imports had increased to 7,123 million U.S. dollars, in 2006 LED imports reached U.S. $ 88.5 million , annual growth rate of more than 11.93 % to2007 India's economic growth is more rapid , LED amount of imports hit record highs .
Industry for heat from thermal conductivity and heat both sides have always discussed. For heat dissipation in the LED industry too much emphasis on additional heat conducting layer in front of the practice of general practice in the industry put forward different fundamental solution.
From the viewpoint of heat conduction , the traditional MCPCB bottom aluminum plate is simply redundant, the thermal conductivity between the copper foil usually hard texture plastic material , the temperature rises because of copper and aluminum sizing different coefficients of thermal plastic resulting intermediate increasing gap layer interface thermal resistance.
MCPCB thermal aluminum industry preferred substrate is an aluminum block from the bottom and the upper foil group , the middle filled thermal plastic (Adhesive) formed. Copper resistance 0.001cm2? K / W is close to 0 , the bottom thermal resistance of aluminum 0.08cm2? K / W, but the thermal plastic thermal resistance up to 1cm2? K / W, true to the MCPCB thermal resistance measured about 2 ~ 4cm2? K / W.
Taiwan's Ministry of Economic Affairs recently estimated that if the future Taiwan 2,300,000 lights can be changed to LED lights , 1 year can save 750 million kWh of electricity, as well as NT $ 1.5 billion in electricity, while reducing 517,000 tonnes carbon dioxide emissions.
We saw some interesting phenomena . That is exhibited in some large manufacturers lights, stage lights, outdoor wall lights found on the heat lamp light shell coated with a thick layer of black paint tradition , like the led tube light painting is the same as water pumps .
Interviews , we learned that manufacturers say that because it is used in the outdoors, to endure climate change, acid rain , and had sprayed paint protection. Why use black paint it ? The answer is actually more dirt , dirty comparison can not see.
Why use paint it ? Do not worry about the paint will form a thermal resistance caused by the led tube light failure ? The answer is , if anodized still have thermal protection , and exposed for a few months will fail , had to use paint protection , even if the light fades will also try to get through the engineering units of acceptance fine.
Unexpectedly, this external protective paint confused efforts row cooling module out of the heat and seal scattered back , resulting in improper cooling, a serious cause the LED epitaxial lumen.
Temperature is actually failure LED street light key issues , but why LED lights on the card in this link. LED street light power is greater than the household lamps , so the manufacturers in the cooling fins substrate , cooling fan design painstakingly , until fully assembled but also outside in the fixture and cooling modules plus paint protection against weather erosion.
When importing calculated heat flux , the heat flux q = Q ( total heat ) / A ( surface area ) = (T1-T2 temperature difference )? K ( thermal conductivity ) / l ( by length) of the LED constant heat flow q is a fixed constant, the thermal resistance (Rt) is divided by the length l of the thermal conductivity value of k , the shorter the length of heat conduction can effectively reduce the overall thermal resistance , and the total thermal resistance of the interface with the thermal resistance between , as well as interface interface thermal resistance between the accumulation and rising.
According to the present large-scale street acceptance , LED lamp life test : more than 1,000 hours of life testing, the amount of light attenuation is less than 3% ( dry of lighting ) ; 15,000 hours of life test , the light attenuation is lower than 8%. Pass specification , you'll get the acceptance of public works funds .
If the thermal resistance of the following formula into Rtotal = Rl-s + Rs + Rs-a, a total thermal resistance of the LED thermal resistance between the LED to the substrate , with the substrate resistance (Rs) coupled to the air side of the heat the substrate resistance (Rs-a) the sum of the three . Aluminum plate resistance Rs in general about 2 ~ 3cm2? K / W, the thermal resistance of the substrate to the air side of the heat- up Rs-a 400 ~ 3,000 cm2? K / W, instead of on the substrate side of the bottleneck .