How to Choose the Right LED Lights
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\r\n One application where LEDs (light emitting diodes) shine is in flashlights. Because LEDs have high brightness, low power consumption, long life, small size and other characteristics, they're ideal for portable lighting. You can choose a good LED flashlight if you look for some key features.\r\n
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\r\n\r\n Here are things you should consider before buying led lights:\r\n
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\r\n\r\n Efficiency\r\n
\r\n\r\n Manufacturer’s claims vary wildly about the efficiency of LEDs and can often be quite misleading. The simplest way to ensure that you are comparing “like with like” is to look at the efficiency in Lumens per Watt. That is, how much light do you get for each Watt of electricity used. Today (early 2010), LEDs that are in production range in efficiency from about 20 to 60 Lumens per Watt. New developments should increase this to around 80 or 100 Lumens per Watt over the next few years. This compares with around 10-15 Lumens per Watt for old-fashioned incandescent lamps and 50-100 Lumens per Watt for fluorescent tubes.\r\n
\r\n\r\n Colour Temperature\r\n
\r\n\r\n Early LEDs were mostly a very much higher colour temperature (ie a bluish light) than the typical 2700K colour temperature of a warm white incandescent lamp. This has led many people to think that LEDs gave a “cold” light. LED technology has however advanced a great deal in the last couple of years and some types of LED are available in a range of colour temperatures from warm white (2700 or 3000K) up to daylight (6000K and beyond). LEDs with a higher colour temperature do however tend to be slightly more efficient than those with a lower colour temperature so some companies offer these as a way of making their products seem brighter. To replace standard incandescent or halogen lamps, a colour temperature of around 2700K to 3300K is preferred. Some companies use non-standard terms when describing the colour of LEDs such as “natural white” or “office white” which cannot be readily compared with other products. To ensure that you are comparing like with like always check the colour temperature.\r\n
\r\n\r\n Colour rendering\r\n
\r\n\r\n The colour rendering of LEDs varies quite markedly between brands. For some applications this is not particularly important but for ambient lighting it is important to check the quality of light emitted. The LEDs that we offer for ambient lighting all have good colour rendering, comparable to that of a good quality fluorescent tube. Many manufacturers do not however quote a colour rendering index for their LEDs so we are rarely able to quote specific figures.\r\n
\r\n\r\n Heat output\r\n
\r\n\r\n LEDs give off relatively little heat but do run reasonably warm and often incorporate a heat sink to dissipate any excess heat and maintain the LEDs at optimum operating temperature. Compact lamps such as miniature spot lights can thus still get reasonably warm whereas larger bulbs and candles certainly cool enough to touch when operating.\r\n
\r\n\r\n Rated Life\r\n
\r\n\r\n The one area where LEDs really score highly is in their rated operating life which typically ranges from 20,000 to 50,000 hours. This is 20 to 50 times longer than a typical incandescent lamp so LEDs are ideal for use in areas where maintenance is difficult or long life is important.\r\n
\r\n\r\n Watts\r\n
\r\n\r\n Watts is how people think about power usage and how bright a light will be. However when working with LED lights, we all have to change our thinking from watts to “lumens”. Why?\r\n
\r\n\r\n The simple answer is that a 10 watt LED bulb manufactured by 5 different manufacturers will likely have 5 different light outputs. In fact some LED bulbs can be twice as bright at the same wattage. The reasons for this are numerous, but we will mention 3 here:\r\n
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- \r\n The brand of LED chip contained in the light will directly affect brightness\r\n \r\n
- \r\n The colour of an LED (even with the same brand chip) will significantly affect light output\r\n \r\n
- \r\n The quality and type of materials used to make the light housing will greatly affect brightness\r\n \r\n
\r\n Below is a basic guide on how to choose the correct wattage you'll need for different uses and circumstances: Notice the large variance in light output.\r\n
\r\n\r\n Some LED chips will give 50 lm/w while others can give in excess of 100 lm/w. The figures below are conservative.\r\n
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\r\n\r\n \r\n\r\n \r\n\r\n Watt Power(w)\r\n
\r\n\r\n \r\n\r\n Lumens range (lm)\r\n
\r\n\r\n \r\n\r\n Used for:\r\n
\r\n\r\n \r\n\r\n \r\n\r\n 3w\r\n
\r\n\r\n \r\n\r\n 150 to 240\r\n
\r\n\r\n \r\n\r\n Candle bulbs and spotlights.\r\n
\r\n\r\n Used in lamp shades, garden fittings, under benches. Where the light source is located close to the object being illuminated.\r\n
\r\n\r\n \r\n\r\n \r\n\r\n 4w\r\n
\r\n\r\n \r\n\r\n 200 to 310\r\n
\r\n\r\n \r\n\r\n Used for the same as 3w when a little more light is desired\r\n
\r\n\r\n \r\n\r\n \r\n\r\n 5w\r\n
\r\n\r\n \r\n\r\n 250 to 380\r\n
\r\n\r\n \r\n\r\n This is used a lot in led downlight fittings, led bulbs for bedside lamps and wall fittings. Colour changing bulbs often come in this wattage.\r\n
\r\n\r\n \r\n\r\n \r\n\r\n 6w\r\n
\r\n\r\n \r\n\r\n 300 to 480\r\n
\r\n\r\n \r\n\r\n Good middle of the range wattage used for general lighting in domestic homes for hallways & bedrooms. Can also be used for accent lighting of paintings. Also commonly used in LED bulbs for lamp shades.\r\n
\r\n\r\n \r\n\r\n \r\n\r\n 7w\r\n
\r\n\r\n \r\n\r\n 310 to 500\r\n
\r\n\r\n \r\n\r\n 7w is used for the same reason as 6w when more light is desired. A very common wattage for MR16 and GU10 LED spotlights to replace 20w or 35w halogen downlights.\r\n
\r\n\r\n \r\n\r\n \r\n\r\n 9w\r\n
\r\n\r\n \r\n\r\n 320 to 600\r\n
\r\n\r\n \r\n\r\n This is the most popular wattage for downlights and spotlights where general lighting is used. Can be equivalent to or greater than a 35w halogen.\r\n
\r\n\r\n \r\n\r\n \r\n\r\n 10w\r\n
\r\n\r\n \r\n\r\n 350 to 760\r\n
\r\n\r\n \r\n\r\n A 10w LED spotlight such as an MR16 or GU10 will produce light output equivalent to 35w to 50w. This makes it a popular choice for retro-fitting.\r\n
\r\n\r\n \r\n\r\n \r\n\r\n 12w\r\n
\r\n\r\n \r\n\r\n 550 to 1000\r\n
\r\n\r\n \r\n\r\n Used mostly in downlights for higher ceilings or in kitchens where more light is desired & floodlights.\r\n
\r\n\r\n \r\n \r\n\r\n \r\n\r\n 15w\r\n
\r\n\r\n \r\n\r\n 680 to 1300\r\n
\r\n\r\n \r\n\r\n Many brands use this wattage as a 50w halogen replacement. Although a better quality fitting with a lower wattage can also do the job.\r\n
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\r\n\r\n Lumens
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\r\n\r\n Lumens are the measurement of the total amount of light emitted from a light source. You may hear the term ‘lux’ thrown around as well. Lux is simply the amount of lumens in a specified area. 1 lux = 1 lumen/m² \r\n
\r\n\r\n Beam Angles
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\r\n\r\n LED strip lighting and LED bulbs commonly use 120° beam angles. However, if you are purchasing LED spotlights and downlights, you will want to consider which beam angle to use. Below is an easy guide on how to choose your beam angle when choosing lights:\r\n
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