Power Led Car
Power Led Car
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 In Car 12V RED Cigarette Socket DC Power Rechargeable Hand Torch LED Flashlight  US $7.00
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Thermal Characteristics of High Power Leds
High power LEDs are commonly known as power-saving lights that come with power ratings in the range of 500mW to 10 Watts. They are based on technology meant to increase their luminescent efficiency and therefore can be used almost everywhere from car headlights to high-power lamps. They can be characterized on the basis of a few parameters, such as forward voltage, wavelength, luminous intensity and type.
The wavelength is measured in nanometers and is different for all three basic colors – red, blue and green. By setting these colors to different wavelengths we can get a whole range of exciting colors, also called rainbow colors. This is one of the electro-optical characteristics of an LED. Another important variation is the peak wavelength which suffers the lowest loss due to heat.
Every LED has two kinds of voltages – forward and reverse. A light emitting diode can be made to act like a variable resistor or a capacitor by interchanging reverse and forward voltages. Usually the reverse inclusion is the one with the higher voltage – up to 5V.
Some other vital parameters of high power LEDs are axial intensity and luminous flux. Luminous flux is also known as luminous power and it gives the measurement of the perceived power of light. The power is different at different wavelengths and luminous flux is calculated by adding up power ratings at all wavelengths. This is not the actual power measurement; instead it is the measure of the ‘useful’ power of an LED. Power dissipation is the amount of power consumed by the LED. It is also referred to as the energy lost in the form of heat. Another important characteristic is the emitted color. This color is what we see when the LED is switched on. It can be red, yellow, green, blue or white.
One of the most important concerns regarding the design of high power LEDs is the amount of heat produced due to increased efficiency. High temperatures are not suitable for proper LED operation. They serve to decrease its life and make it less efficient. Thermal management in these LEDs is therefore a major concern in order to make them more productive and longer lasting. There is a critical temperature defined for every LED beyond which it is permanently destroyed. The temperature of an LED keeps on changing with the passage of time and therefore it’s important to maintain a chart to record different temperature ratings against time.
There are three ways by which heat can be discharged: conduction, convection and radiation. Traditional incandescent tungsten light bulbs radiate energy in the form of heat. LEDs, on the other hand, conduct heat from one part to another which takes a long time to be released to the atmosphere. The heat sink should be made by using a material which has high thermal conductivity. Aluminum and copper are two of the most widely used heat sink materials.
Radiation takes less time than conduction and therefore tungsten bulbs do not heat up very quickly. When designing high power LEDs, proper heat conduction is a main issue to be addressed.
The temperature of an LED is directly related to its color. White light is produced by combining base colors in their highest values and therefore the temperature is also the highest in case of white light. Some mechanism is required to keep the color constant when temperature changes due to conduction. A color sensor can be used for this purpose.
Wavelength, forward voltage and luminosity are also affected by the junction temperature of the diode and therefore they also have to be optimal in order to make the LED perform well.
Positive feedback or “thermal runaway” is another problem related to high temperature of the LED. This is a condition in which increased temperature causes the above-mentioned parameters to change unexpectedly resulting in a further increase in temperature. This situation can be critical to the operation of an LED and has to be prevented. It happens when the LED is directed to consume more power in order to produce the desired color. As a result, more heat is produced which raises the temperature and hence the effect.
Thermal runaway is more pronounced when increased junction temperature decreases the luminous intensity and as a result the color sensor reports there is not enough light. This negative cycle goes on and on until the critical temperature is reached and the LED is destroyed. Thermal sensors can be used to correct this problem which constantly measure the junction temperature and make the system shut down if there is an alarming condition.
However, usually this mechanism is not advisable in these LEDs because it makes them useless and obliterates their purpose. Other methods like using natural graphite to spread heat are more practical and useful. This material conducts a large portion of heat dissipated by the LED and as a result releases it to the atmosphere more quickly.
In conclusion, the most important thing to consider in a high power LED design is the selection of appropriate materials that are not affected by the unexpected rise in temperature. This is to ensure that the LED works at all times without shutting down because of the failure of one of its components. Efficient thermal management can increase the critical temperature of an LED and as a result its reliability and longevity is also enhanced. These design decisions on the part of manufacturer help the customer save money and make the most out of these powerful and efficient high power LEDs.
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Connectland / Connectland Car Multi 12V Power Socket Power Inverter w/2 Car Power Sockets USB & LED Light / CL-CAR-U2SOC $20.13 Connectland - Connectland Car Multi 12V Power Socket Power Inverter w/2 Car Power Sockets USB & LED Light - CL-CAR-U2SOC |
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Car LED Light (YCL-643-W) $11.99 SpecificationSize: 18 16 5Feature: 1.shell is made from plastic of high temperature resistant,circuitry adopts high brightness led as lamp-house 2.Work Voltage : DC12V: Consumed power: 0.8W 2: work Current:60MA 2 3.Light body angle can be adjustable freely 4.lnstalled handily ,and decorate your car 5.lighting color is various and of your choice 6.Fix lamp body on the two sides of the front or the rear of car,Power line connect to the car lamp power supply 7.The product is only available to DC12V car, DC24V vehicles need to match correctly 8.Only for driving as auxiliary lamp in the evening |
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Shark Fin - Wind Power Car LED Light $3.99 This product application without power supply and wiring,just light up by wind while the speed rate reach 30km/h.It comes with adhesive on the back, just peel and stick on,very easy to install.Approx. size: 13.5 (L) x 5 (W) x 5.5 (H) cm. Features: Lights up in 3 leds when the speed rate of automobile reaches 30KM/h, supper light makes the driving colorful and safety at night. Warning to other vehicles and passer-by. Applied to Car, Motorcycle, Bike and Scooter. Comes with adhesive on the back, just peel and stick.Please use detergent to clean the surface of the target before stick it on. Application without power supply and wiring. Light up by wind power while vehicle is in motion. Material : Solid PVC. Package Contains : 1 x Wind power shark fin LED |
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Cool Wind Power Blue LED Light Car Decoration Lamp $11.49 Description:New generic and interesting Cool Wind Power 2 Blue LED Light Lamp Car Decoration.The Car Decoration Lamp is specifically designed for car decorative lamp.Cool LED Lamp features stylish design with 8 LED bulbs.Wind power, no battery, no wiring required.The strong wind, the bright of the lamp.Easy placing at any part of your car or motor by its strong adhesive2 blue LED lights, add colors to your carPlease use detergent to clean the surface of the target before stick it onMaterial: Solid PVCSize of Blue LED Car Lamp: approx. 12 x 1.5 x 3cmColour: as picture showWeight: 97gPackage included:1 x Wind Power Car Lamp |
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Wind Power Shark Fin LED Light Lamp Car Decoration $8.49 Description:New generic and interesting Wind Power Shark Fin 2 Blue LED Light Lamp Car DecorationThe Shark Fin LED Light is specifically designed for car decorative lampWind Power Car Light features stylish streamline body and shark fin shapeWind power, no battery, no wiring requiredThe strong wind, the bright of the lampEasy placing at any part of your car or motor by its strong adhesive2 blue LED lights, add colors to your carPlease use detergent to clean the surface of the target before stick it onMaterial: Solid PVCSize of LED Decoration Light: approx. 11.9 x 6.2 x 5.6cmColour: blackWeight: 68gPackage included:1 x Car Wind Power LED Light |
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Red Blue Wind Power Cool LED Light Lamp for Car Decorative $8.49 Description:New generic and interesting Cool Wind Power 2 Red Blue LED Light Lamp Car Decoration.Cool LED Car Lamp features stylish design with blue and red colors.Wind power, no battery, no wiring required.The Car Decorative Lamp is specifically designed for car decorative lamp.The strong wind, the bright of the lamp.Easy placing at any part of your car or motor by its strong adhesive2 red blue LED lights, add colors to your carPlease use detergent to clean the surface of the target before stick it onMaterial: plasticSize of Red Blue Light Lamp: approx. 4 x 2.7 x 2.8cmColour: as picture showWeight: 33gPackage included:2 x Wind Power Car Lamp |
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Car LED Lights (YCL-648) $19.99 SpecificationSize: 21 17.5 5Features: 1.using superhigh light led as the illuminant,saving electric power,super high ligt,long life 2.neat and beautiful form design,it installs SCM control with various twinking 3.The broken,flashing,constant-tranche control,the work of each state have led instructions |
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Car Wind Power Decor Antenna Green Blue Red LED Light $9.2 Description:If your country doesn't allow using the decorative antenna, we'd advise you do not buy it.Made of good quality plastic material and power by wind.When the wind power is enough, the head of the Car Decor Antenna will give out green, red light, but the tail will give out blue light.With LED light, the LED Decor Antenna will warn other vehicle passing by for safe divering.The LED Light Antenna is easy to install as the double-faced adhesive on the base.This Wind Power Antenna for car decoration purpose - not a genuine antenna.Base Size: ~2.3" x 1.5" (L*W)Total height: ~2.4"Color: silver tone & clear whiteWeight: 73.3gPackage Contains:1 x Car LED Decor Antenna |
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