Nowadays, Public LED street lamps are widely used in the lighting of urban roads, blocks and scenic spots. LED street lights save electricity, which is its important advantage. Compared with other lighting forms such as high-pressure sodium lamps, what are the characteristics of LEDs?
LED street lights are small in size: LED is basically a small chip encapsulated in epoxy resin, so it is very small and very light.
Low power consumption: LED power consumption is very low, generally speaking, the working voltage of LED is 2-3.6V. The working current is 0.02-0.03A. This means: it consumes no more than 0.1W of electricity.
Long service life: Under the right current and voltage, the service life of the LED can reach 100,000 hours. High brightness, low heat.
Environmental protection: LEDs are made of non-toxic materials. Unlike fluorescent lamps, mercury can cause pollution. At the same time, LEDs can also be recycled.
Rugged and durable: LED is completely encapsulated in epoxy resin, which is stronger than light bulbs and fluorescent tubes. There is no loose part in the lamp body, these characteristics make the LED can be said to be difficult to damage. High brightness, energy saving and electricity saving, high efficiency, fast response speed, good shock resistance and long service life. In order to illustrate the characteristics of white light LEDs, let’s take a look at the status of the current lighting sources. The luminous efficiency of incandescent lamps and halogen tungsten lamps is 12-24 lumens/watt; the luminous efficiency of fluorescent lamps and HID lamps is 50-120 lumens/watt.
For white LEDs: In 1998, the luminous efficiency of white LEDs was only 5 lumens/watt. By 1999, it had reached 15 lumens/watt. This index was similar to ordinary household incandescent lamps. In 2000, the luminous efficiency of white LEDs It has reached 25 lumens per watt, which is similar to the tungsten halogen lamp. In 2005, the luminous efficiency of LED reached 50 lumens/watt, and in 2010, the luminous efficiency of LED reached more than 100 lumens/watt. The working current of the white LED can reach the ampere level. It can be seen that the development of white LEDs as home lighting sources will become a possible reality.
If white LED is used for lighting, it will not only have high luminous efficiency, but also have a long life (continuous working time is more than 10,000 hours), and almost no maintenance is required. At present, the German Hella company uses white LEDs to develop aircraft reading lights; a street in the Australian capital Canberra has used white LEDs for street lighting; my country’s urban traffic management lights are also replacing early traffic order indicators with white LEDs. It is foreseeable that in the near future, white LEDs will surely enter the home to replace the existing lights. LED light source has the advantages of using low-voltage power supply, low energy consumption, strong applicability, high stability, short response time, no pollution to the environment, multi-color luminescence, etc. Although the price is higher than existing lighting equipment, it is still considered to be inevitable To replace existing lighting devices.
What are the disadvantages of Public LED street lamps?
- The power of a single LED is low. In order to obtain high power, multiple parallel connections are required.
- Low color rendering. The color displayed under the LED illumination is not as true as that of an incandescent lamp. This must be analyzed from the spectral distribution, which is a technical problem.
- 3, light spot. Due to defects in the manufacturing process of the white LED itself and the matching error with the reflector cup or lens, it is easy to cause the “yellow circle” problem.
- 4, LED illumination uniformity problem. If the secondary optical design is not carried out, the illumination of the LED is relatively concentrated, so the secondary optical design must be carried out to make the light intensity distribution chart look like a bat.
- The problem of LED light decay. Compared with low-power LEDs, the light decay of high-power LED street lights will be much better. However, low-power LEDs emit very little heat. The high-power LED has a problem that cannot be solved by heat dissipation, and the brightness will be significantly reduced after heating, so the power cannot be increased. The largest Spark LED street light currently on the market is 360W.
What are the advantages of Public LED street lamps?
- Low power consumption and low operating cost: LED light sources with the same luminous efficiency are more than 80% energy-saving than traditional light sources. For example, a 2000-meter bridge LED guardrail light only consumes 10 kilowatt-hours of electricity for 1 hour, and the electricity bill for a year is higher than that of traditional light sources. The lamp saves tens of thousands or even hundreds of thousands of dollars.
- Low cost of protection: LED lamps are stable in operation, have low demands on the operating environment, and are not frequently replaced due to the influence of harsh weather conditions.
- Long lifespan: LED lamps use solid semiconductor chips to convert electrical energy into light energy to emit light, plus epoxy resin encapsulation, which can accept high-intensity mechanical shock and sensation. The life span of a single LED tube is 100,000 hours, and the life span of the light source is more than 20,000 hours. According to 12 hours of operation per day, the life span is more than 5 years.
- High luminous efficiency: white light, halogen tungsten light effect is 12~24 lumens/watt, fluorescent lamp is 50~120 lumens/watt, and the light source adopts black body radiation, and only about 10% of the emitted energy can be used Visible light, the rest is useless heat; in order to obtain one color, it is necessary to use a color filter to remove other colors, resulting in energy waste. The LED luminous efficiency is 50~200 lumens/watt, the spectrum is narrow, and the monochromaticity is good. Almost all declared light can be used, and the color light can be directly declared without filtering.