Powerful LED Matrix In Lighting: Device And Application Features
steemiteducation·@amity123·
0.000 HBDPowerful LED Matrix In Lighting: Device And Application Features
<center></center> ***Since the development of the first practical **LED**, half a century ago, the revolutionary invention still undergoes progressive changes to this day, becoming more and more sophisticated and increasingly technological and useful.*** The **electroluminescence** of the semiconductor junction, in the recombination of electrons and holes, is now placed at the basis of **super-economic light sources. LEDs**, often called LED (short for English light-emitting diode), lamps are gradually gaining a stable position in the market of modern energy-saving lighting technologies, both for household needs, and for businesses and even for street lighting systems. <div class=pull-left>https://res.cloudinary.com/hpiynhbhq/image/upload/v1517048315/wgqvkprlgohvbhor8aym.png</div> LED lamps outperform the safety of compact fluorescent lamps, which contain mercury, and incandescent lamps and are now a remnant of the distant past. The main reason for the replacement of incandescent lamps with LED light sources is that the incandescent lamp emits in a very wide spectrum, a large part of which simply does not work for illumination. Only 5 percent of all power consumed by the incandescent lamp goes to lighting, and the rest to heating. <center></center> This is why the very powerful LEDs and LED matrices (monolithic assemblies), for the replacement of industrial luminaries, are so widely represented in the market recently. The LED emits in a fairly narrow spectral range, for example, the orange LED has a wavelength in the range of 590 nm to 610 nm. <center></center> The advantages of LED light sources include: * high luminous efficiency, comparable to sodium lamps (160 lumens per watt achieved), * strength and vibration resistance, long service life (up to 100,000 hours), * a wide range for choosing the light temperature (from a warm 2700 K to a cold 6500 K), * purity of the spectrum, provided by the device itself. Because of the low inertia, light included immediately at full brightness regardless of ambient temperature, and the on-off has no substantial influence on the life of LEDs. The radiation angle can be from 15 to 180 degrees. The use of such tools is completely safe for humans due to low supply voltage, low operating temperature, and of course, the environmental friendliness provided by the absence of mercury and phosphorus, as well as the ultraviolet part of the radiation in the spectrum. It should, however, be remembered that high temperatures are harmful to any semiconductor, so do not allow heating above 60-70 degrees Celsius. <center></center> Powerful LED matrixes are assemblies of several crystals in one block. The radiating crystals coated with phosphor are connected in series-parallel to optimize the current consumption. The flat surface of the unit is a transparent plastic coating that allows the installation of additional optics to create the necessary light scattering diagram. The matrices are supplied with a fairly thick copper or aluminum substrate with mounting holes for mounting the unit to the heat sink. The smooth surface of the substrate ensures a reliable contact of the unit with the heat sink. The installation should be done carefully, so as not to deform and damage the housing. Apply heat-conducting paste to the entire surface of the substrate. The cross-section of the connecting wires should not be less than 0.5 square millimeters, and the heat-transfer area per watt should be about 20-30 square centimeters at a temperature of surrounding objects of 25-35 degrees Celsius. Such matrices are produced at different rated power, up to 300 watts or more. In principle, there are no restrictions on the size of matrices. The average value of the operating voltage for one crystal is about 3.4 volts, and the current is about 350 milliamps. These values may vary slightly, but the voltage should not be exceeded because the LEDs have a steeply increasing current-voltage characteristic and will quickly burn if the current exceeds the critical value for the crystal. The use of a radiator with a reserve in area - the best insurance for a long, reliable and trouble-free operation of the LED matrix. If we limit the current through the crystal to 320 milliamperes, the light flux will decrease by 3-5%, but the lifetime of the LED crystal increases by an order of magnitude, the conditions of its electrical supply will be ideal. *Power supply for LEDs and Circuit Diagram*  <div class=pull-left>https://res.cloudinary.com/hpiynhbhq/image/upload/v1517048872/fz3luqclp1pejjzxiqzj.png</div> The source of power for LEDs can be any source with stabilization of the load current, and if there is no current stabilization, then a significant margin must be provided to exceed the maximum permissible current. Changing the supply voltage by 1 volt can lead to an increase in current strength of two to three times and the consequence will be the degradation of the crystal (the crystal will be damaged - the light flux will decrease) or the darkening of the phosphor. When designing combinations of groups of LEDs in a series-parallel connection, preferably a serial connection, to avoid high operating currents. If the working temperature of the crystal becomes longer than the optimum value for a long time, the phosphor will darken by temperature and lose its functions. Darkening and destruction of the phosphor can also cause direct sunlight, if they continue to affect the surface of the LED. In the design of the power supply, it is desirable to include the thermal relay by placing its sensor on the radiator of the luminaire. If you plan to use the LED matrix in the winter on the street, you need to take into account that electrolytic capacitors in the power supply have a restriction on use at low temperatures, therefore, the best solution will be to place the power supply in the room. When using LED matrices outdoors at low temperatures, it should be remembered that the efficiency will increase significantly, and the light output will increase by 10-20 percent of the nominal value. And after 500-1000 hours of operation, the light output in any case will be more by 5-10 percent, this is a feature of crystals called the "training effect". Particular attention is required and the choice of radiator for street lighting, it should not contain excess protrusions, depressions and bends, so that natural convection was maximum, and debris and dirt could not accumulate on its surface. The power supply of the luminaire is preferably arranged so that all the moisture that accumulates inside the luminaire does not in the slightest degree affect the elements of the circuit. Every year, the technology of producing high-power LED matrices is being improved, manufacturers are looking for better versions of the phosphor. At the same time, most manufacturers use yellow phosphors, they are modified versions of yttrium-aluminum garnet doped with trivalent cerium. LED lighting technology is effective, and the designs of them are quite simple. They have found wide application in searchlights, lamps, LED ribbons, decorative lighting equipment and in simple flashlights. Their light output reaches 5000 lm. Today, LED modules are used to illuminate buildings, streets, advertising structures, tunnels and bridges, fountains, they are used to illuminate office and industrial premises, home interiors and furniture elements, as well as in various modern design projects. During the holidays, powerful LED lighting systems adorn the facades of buildings, trees, and other objects. Reliability of LED light sources makes it possible to use them in hard-to-reach places for frequent replacement. <center></center> Now in many countries of the world, LED lighting has promptly supplanted the others. Many cities plan to soon switch to LED street lighting. <center></center> *** *** *References for Text and Images :* 1. https://en.wikipedia.org/wiki/Floodlight 2. https://lightpolesplus.com/0842-site-security-application-custom-fiberglass-light-poles-miami-florida/ 3. http://www.gigaled.gr/en/content/6-repair-maintenance-of-led-flood-lights 4. https://lightpolesplus.com/0842-site-security-application-custom-fiberglass-light-poles-miami-florida/ 5. http://blog.lightingever.co.uk/choose-led-work-lights-for-better-work-performance/ 6. http://versedtech.org/20716/using-led-flood-lights-correctly/ 7. https://www.linkedin.com/pulse/types-lighting-work-zones-harry-zhu *** <center> *Support @steemstem and the #steemstem project - curating and supporting quality STEM related content on Steemit* </center> <center>https://steemitimages.com/0x0/https://steemitimages.com/DQmeJgsbM5K3pUC8kPBToDKRxE2gijUXvgvX6oUiBgaaiyk/atom.gif </center>
👍 princeace, sundararaj, busy.org, zulman, justtryme90, steemstem, lafona-miner, dna-replication, curie, liberosist, meerkat, roelandp, locikll, anwenbaumeister, hendrikdegrote, spiry-btc, kushed, pharesim, lemouth, anarchyhasnogods, mobbs, the-devil, foundation, himal, lamouthe, rachelsmantra, nitesh9, kerriknox, gra, rjbauer85, pearlumie, amavi, dber, gentleshaid, mystifact, kenadis, carloserp-2000, mountainwashere, hadji, fredrikaa, abigail-dantes, leczy, chicoree, steembasicincome, steemslav, youssefb, ikidnapmyself, minnowpowerup, tormiwah, laxmank,