LED spotlights
LED spotlights are spotlights that use light-emitting diodes as the light source. Traditional spotlights mostly use halogen lamps, which have low luminous efficiency, consume more power, increase the temperature of the illuminated environment, and have a short service life. LED light sources are far superior to traditional lighting fixtures in terms of lighting principles, energy saving, and environmental protection.
Chinese name: LED spotlight
Foreign name: Ledspotlight
Alias: Light-emitting diode
Occupation: LED
< p>Graduating school: Comparative power consumption, increased ambient temperature when exposed to lightMain achievements: The unidirectional nature of LED light provides perfect support for spotlight light distribution
Representative works : Principle of luminescence
Light source: light-emitting diode
Light-emitting characteristics: unidirectional
Advantages: LED spotlights are cheaper
Use Lifespan: between 50,000 and 150,000 hours
Cost-price advantage
The English name of LED spotlights is Ledspotlights. It is the most concerned energy-saving and environmentally friendly product at the moment. It uses LED as its source. There are more and more lamps made of light sources, among which the most popular ones are LED spotlights, because compared with other LED lamps, LED spotlights are cheaper.
1. LED spotlights can be driven using low-voltage direct current: they have the advantages of small load, weak interference, and have low requirements on the use environment. 2. LED spotlights can better control the composition of the luminous spectrum, so they can be well used for local or accent lighting in museums and exhibition halls.
3. LED spotlights have very strong luminous directivity: the brightness attenuation is much lower than that of traditional light sources, and the price of LED spotlights is affordable.
4. The response time of LED spotlights is very fast: at the microsecond level, as soon as the switch is turned on, it will light up immediately, without any delay or flickering.
5. The light energy emitted by LED spotlights is highly concentrated: it is concentrated in a smaller wavelength window and has high purity.
6. The lifespan is very long, generally between 50,000 and 100,000 hours. Because LEDs are semiconductor devices, even frequent switching will not affect the service life.
7. Environmentally friendly, LED spotlights do not need to add "mercury" during the production process, do not need to be inflated, do not need a glass shell, have good impact resistance, good shock resistance, are not easily broken, and are easy to transport. , very environmentally friendly, known as "green energy", and the price of LED spotlights is affordable.
8. Energy saving, the spectrum of LED spotlights is almost entirely concentrated in the visible light band, and its luminous efficiency can reach 80 to 90%. Most people think that it is a great innovation that energy-saving lamps can save 4/5 of energy, but LED spotlights can save 1/2 of energy than energy-saving lamps. This is a greater reform of solid light sources.
In addition, LED spotlights also have other advantages. They have high light quality and basically no radiation. LED spotlights are affordable and are a typical green lighting source; they are reliable and durable, and have extremely low maintenance costs. etc. Precisely because LED spotlights have the above characteristics that other solid light sources cannot match, LED will be the mainstream light source in the lighting industry in 10 years.
Since LED bulbs are structurally more complex than halogen spotlights, the product price will be higher than that of halogen lamps even in mass production. But as more and more people understand and accept it, and large-scale production slowly rolls out, the price of LED spotlights will soon reach a level that is acceptable to people. If you calculate an energy saving account when purchasing, you will find that even at a higher price, based on one year of use, the initial purchase cost + 1 year's electricity bill is lower than traditional halogen spotlights. The service life of LED bulbs can be as high as more than 50,000 hours.
Classification
At this stage, LED spotlights are mainly used to replace traditional tungsten halogen lamps, so the overall dimensions refer to the IEC60630 standard, and the lamp head refers to the IEC60061-1 standard. According to the situation of traditional spotlights, LED spotlights mainly include MR16, PAR16, PAR20, PAR30, and PAR38. Among them, MR16 usually uses GU5.3 lamp holders; PAR16 mainly uses GU10, E26 (America)/E27 (Europe and China), and E14 lamp holders; PAR20/PA30/PAR38 mainly uses E26 and E27 lamp holders.
Various lamp holders (from left to right: E14, E17, E26, E27, GU10, GU5.3)
Structural features
Types of spotlights There are many, mostly used to create effects and embellish the atmosphere. The colors include pure white, beige, light gray, gold, silver, black and other tones; the shapes include long and round, and the specifications and sizes vary. Because of its exquisite shape, it is very decorative. Therefore, generally speaking, they are often placed in highly decorative places in various combinations to reflect the owner's exquisite life and unique taste from the details. When choosing, focus on the appearance grade and the light and shadow effect produced. Because it is a typical decorative lamp, the brightness does not need to be considered too much.
Spotlights can be placed around the ceiling or on top of the furniture, or they can be placed in the wall, dado or skirting.
1. Energy saving: LED lights with the same power consume only 10% of the power of incandescent lamps, which is more energy-saving than fluorescent lamps.
2. Long life: LED lamp beads can work for 50,000 hours, which is longer than fluorescent lamps and incandescent lamps.
3. Dimmable: The previous dimmers have always been for incandescent lamps. When the incandescent lamp is dimmed, the light will glow red; it is difficult to see a fluorescent lamp dimmer. This is a dimming technology that has been around for many years. The main reason for the lack of development; LED can be dimmed again, and it has the same color whether it is bright or dark light (the color temperature is basically unchanged), which is obviously better than the dimming of incandescent lamps.
4. Can be switched on and off frequently: The life of the LED is calculated based on the time it is lit. Even if it is switched on and off thousands of times per second, it will not affect the life of the LED. In decoration and other occasions that need to be turned on and off frequently, LED lights There is an absolute advantage.
5. Rich colors: There are various colors such as pure white light, warm white light, red, green, blue, etc., whether it is a small colorful light used for decoration next to the headlight in the living room or a neon light, it is very bright.
6. Low calorific value: Like spotlights, many 220V spotlights break down within a few days of use because they generate heat. Although the calorific value of 12V halogen spotlights is lower than that of 220V spotlights, their brightness does not reach the nominal value due to insufficient power of the transformer. With LED spotlights, you can work for a long time without a transformer.
Structural composition
LED spotlights are mainly composed of shells, lamp beads, aluminum base plates, and drivers. The specific analysis is as follows:
LED spotlight shell: baking paint , the complete set of two kinds of electroplated shells includes lamp cover, lamp cup, base, aluminum base plate, lens, screws, suitable for MR16, GU10 lotus shape, beautiful, generous and good heat dissipation performance.
LED spotlight beads: six-pin RGB, special for spotlights, red light: 40lm green light: 60lm blue light: 15lm all use 350mA current.
LED spotlight driver: Global universal input voltage (220V) constant current output to ensure the safety of high-power LED use. High power factor, greater than 0.98. Isolated power supply isolation voltage is 3000V. Over-temperature protection, short-circuit protection , open circuit protection can drive all 3W LEDs (including red and yellow) using ceramic capacitors, long life design, high reliability up to 50,000 hours, the whole lamp can pass safety tests, isolation voltage reaches 3750V, can pass EMC test, small size 24mm* 18mm, with Chinese and American patents.
Optical properties
LED provides monochromatic light with a large half-width. Since the energy gap of the semiconductor decreases with the increase of temperature, the peak wavelength it emits increases with the increase of temperature. It grows with the rise of temperature, that is, the spectrum red shifts, and the temperature coefficient is +2~3A/. LED luminance L is approximately proportional to the forward current. As the current increases, the luminous brightness also increases approximately.
Heat dissipation
Conventional methods
Use ordinary thermal conductive sheets to dissipate heat for LED spotlights. The thermal conductivity is average and cannot dissipate heat well.
Liquid heat dissipation
Foshan Zhongnan Semiconductor Lighting Research Institute has researched and invented a liquid heat dissipation method to successfully solve the heat dissipation problem of high-power LED and the heat dissipation problem of small-sized LED spotlights, and achieved A historic breakthrough that contributes to the problem of difficult heat dissipation of LED spotlights.
Heat pipe cooling
Use heat pipes to dissipate heat for LED spotlights, just like computer CPU heat pipes to dissipate heat. In this way, the size becomes larger and more bulky.
Lifespan
Because LED spotlights use solid light-emitting diodes as the light source, the lifespan mainly depends on the solid LED light source and driver heat dissipation part. In 2012, the lifespan of the LED light source has reached More than 100,000 hours. With the continuous development of LED technology and the widespread popularization of application technology, the driving and heat dissipation aspects have basically reached a relatively ideal state. The life span of commercially available high-quality LED spotlights has basically reached 10,000-50,000 hours, which is almost the same as that of ordinary halogen lamps. 10-50 times that of spotlights. LED lighting products save up to 80% of energy and are almost maintenance-free. There is no need to replace parts frequently. The cost savings can be recovered in about half a year. The green and environment-friendly semiconductor electric light source has soft light and pure spectrum, which is beneficial to workers' vision protection and physical health.
Scope of application
LED spotlights are mainly used for decoration, commercial space lighting and architectural lighting. With the development and progress of LED technology, the performance advantages of LED spotlights on the market It is very outstanding. It uses high-purity aluminum reflective plates, the most accurate beam and the best reflection effect; symmetrical narrow-angle, wide-angle and asymmetric light distribution systems, and the projection lights are equipped with scale plates, people can easily adjust the illumination according to the scale angle. In addition, in order to facilitate maintenance, the LED projection lamp uses a back-opening replacement bulb. The lighting decoration effect is first-class. LED floodlights can achieve dynamic effects such as gradient, jump, color flash, random flash, gradient alternation, chasing, and scanning. LED projection lights, LED underwater lights, LED underground lights, LED wall washers, etc. can be used independently or interactively to produce more varied effects. LED projection lights are mainly used in single buildings and historical building groups. The market development prospects are promising for exterior wall lighting, green landscape lighting, building interior and exterior lighting, billboard lighting and other specialized facility lighting, as well as atmosphere lighting for entertainment venues such as bars and dance halls.
Production process
1. Cleaning: Use ultrasonic cleaning to clean the PCB or LED bracket and dry it.
2. Mounting: Prepare the bottom electrode of the LED tube core (large wafer) with silver glue and then expand it. Place the expanded tube core (large wafer) on the spindle table and examine it under the microscope. Use a crystal pen to install the tube cores one by one on the corresponding pads of the PCB or LED bracket, and then sinter to solidify the silver glue.
3. Pressure welding: Use an aluminum wire or gold wire welder to connect the electrode to the LED die as a lead for current injection. If the LED is directly mounted on the PCB, an aluminum wire welding machine is generally used.
4. Encapsulation: Protect the LED die and welding wires with epoxy by dispensing glue. Dispensing glue on the PCB board has strict requirements on the shape of the cured glue, which is directly related to the brightness of the finished backlight. This process will also undertake the task of dotting phosphor (white light LED).
5. Welding: If the backlight uses SMD-LED or other packaged LED, the LED needs to be welded to the PCB board before the assembly process.
6. Film cutting: Use a punch to die-cut various diffusion films, reflective films, etc. required for backlight sources.
7. Assembly: According to the drawing requirements, manually install the various materials of the backlight in the correct position.
8. Test: Check whether the backlight photoelectric parameters and light uniformity are good.
9. Packaging: Pack and store the finished products as required.
Purchase
Spotlights are divided into low-voltage and high-voltage. It is best for consumers to choose low-voltage spotlights, which have a longer life and higher luminous efficiency. The light efficiency of spotlights is reflected by the power factor. The larger the power factor, the better the light effect. The power factor of ordinary spotlights is around 0.5 and is cheap. The power factor of high-quality spotlights can reach 0.99, which is slightly more expensive.
Spotlights are generally used to enhance the lighting of decorative objects. They are usually embedded in the ceiling or wall. The spotlights generally emit a higher temperature when working, so be sure to buy high-quality products, otherwise There will be safety risks.
When using spotlights, they must be used with a transformer, and the lamp beads should also be of good quality. Otherwise, the lamp beads of the spotlights are easy to break. Think about it, the lamp beads of the spotlights in the ceiling are quite expensive to replace. Troublesome.
The quality of spotlights on the market varies from good to bad, and it is difficult to distinguish good from bad with the naked eye. Therefore, it is best to choose brand products when purchasing spotlights and choose matching high-quality transformers.
Difference
It is difficult for many people to distinguish between downlights and spotlights. In home decoration, downlights and spotlights have different uses. Simply put, downlights are Compared with ordinary surface-mounted lamps, lamps that are more concentrating are generally used for general lighting or auxiliary lighting. A spotlight is a highly concentrated light fixture whose light irradiation has a specific target that can be specified. It is mainly used for special lighting, such as emphasizing a very interesting or innovative place. We distinguish the characteristics of the two lamps based on the light source, application location, and price comparison.
1. Light source
Downlights can be equipped with incandescent bulbs or energy-saving lamps. When an incandescent lamp is installed, it is yellow light. When an energy-saving lamp is installed, it can be white light or yellow light depending on the type of bulb. The light source direction of the ceiling downlight cannot be adjusted. We can directly see the energy-saving lamp tube of the downlight, and the waterproof downlight has a waterproof glass cover added to the outside.
Generally, household spotlights use quartz bulbs or lamp beads. Of course, large spotlights do not necessarily use quartz bulbs. Quartz bulbs only have yellow light. Moreover, the light source direction of general spotlights can be adjusted freely.
2. Application location
Downlights are generally installed in the ceiling. Generally, the suspended ceiling needs to be above 150mm before it can be installed. Of course, there are also external downlights. It is a good choice to install downlights in areas without ceiling lights or chandeliers. The light should be softer than spotlights.
Spotlights can generally be divided into track type, point-hung type and built-in type. Spotlights usually come with a transformer, but there are also ones without a transformer. Recessed spotlights can be installed in the ceiling. Spotlights are mainly used for places that need to be emphasized or expressed. Such as TV walls, hanging paintings, accessories, etc., can create aura to enhance the effect.
3. Price
Downlights generally come in three types: large (5 inches), medium (4 inches), and small (2.5 inches). The market price of the small size is between 15-20 yuan, the medium size is between 28-32 yuan, and the large size is between 36-48 yuan. Of course, the above prices do not include light sources. There are two types of downlights: horizontal ones and vertical ones. Horizontal ones are slightly more expensive than vertical ones.
It should be noted that spotlights generally cannot be used to illuminate woolen fabrics at close range, nor can there be flammable obstacles at close range, otherwise it may easily cause a fire. Although spotlights consume a lot of power, the effect of embellishment in the appropriate position is very different. Spotlights and colorful lamp cups add a unique touch of decoration.
Installation
1. Process flow:
Installation of lamp stands and lamps→matching of down conductors→light test
2. Installation of lamp stands and lamps:
1) Measure the installation height of lamps (lamp stands) according to design requirements, and mark the poles.
2) Hang the lamp stand and lamps on the pole (heavy lamp stands and lamps can be hung on the pole using pulleys or large ropes), put on the hoops or bolts, and find them according to the design requirements. After adjusting the illumination angle and finding the flatness, tighten the lamp holder.
3) The elevation angles of lamps installed in rows should be consistent and arranged neatly.
3. Match the down conductor: Fix the pin insulator on the lamp stand, tie one end of the wire back to the insulator, and connect it to the lamp holder wire and fuse respectively. Rubber cloth and black tape are overlapped in half and wrapped one layer each. Then, tighten the other end of the wire and tie it back to the street light main wire for winding connection.
4. The phase wire of the lamp should be equipped with a fuse, and the phase wire should be connected to the center terminal of the screw lamp holder.
5. The connection point between the line and the street light main line should be 400~600mm from the center of the pole, and both sides should be symmetrical.
6. There should be no joints in the volley section of the down conductor, and the length should not exceed 4m. If it exceeds 4m, a fixed point should be installed or a steel pipe lead should be used.
7. The place where the wires enter and exit the lamp holder should be covered with a soft plastic tube and made waterproof.
8. Test the lamp: After all installation work is completed, power on, test the lamp, and further adjust the illumination angle of the lamp.