Ten Tips When Buying LED Lights
With most businesses that sell new technology, a good portion of an employees’ time is spent in teaching about the product. I have assembled ten tips for buying LEDs to reduce the learning curve.
1) High power versus low power. Know your lights. High powered energy efficient LEDs have a single LED chip usually from 1-5 watts. These are brighter and have a good ratio of lumens to watts. With recessed or down lighting you will want more power i.e. more light. The further the light is from what you wished illuminated the higher wattage power you will want. Be careful with high powered LEDs since they can generate a lot of heat which will need to be dissipated. This dissipation is done by use of a heat sink, which usually is designed with large curved metallic “fins” but sometime a small built in fan is used.
The low power LED light is made up of many very small LEDs, usually 5 millimeter. These do not produce a great amount of light, about on par with a 40 watt incandescent. They do not produce enough heat to kill the LED lamp so no visible heat sink is needed.
2) That warm white light is not very warm! Learn about the Kelvin scale. The Kelvin scale is often used to measure the color temperature of light sources. Using the scale allows us to quantify, for example the differences between soft white, warm white and cool white. The color temperature of an incandescent light bulb is about 3000k. This is normally construed as warm white. If a light is labeled warm, make sure to check what it claims on the Kelvin scale. Pure white is normally considered about 5000k, to imagine what this looks like picture hospital lighting, very bright white.
3) Check the CRI. The color rendering index (CRI), is a quantitative measure of the ability of a light source to reproduce the colors of various objects faithfully in comparison with an ideal or natural light source. Think how pale people look under certain light sources compared to being in sunlight. Depending on the environment you wish lighted, a CRI of at least 70 is desirable.
4) For online purchases start small! Do not try, all at once, to retrofit your entire home with LED lights from any online company. If you order a few bulbs and you like them go ahead and complete the retrofit of the rest of your home. Many companies do not take returns or have very limited warranties. This is especially true with regards to color variation, which most companies do not considered a defect.
5) Beware of prices that are too low. The LED market is full of poorly made products as well as lights that do not have a warranty at all. Since making LEDs is not an exact science, there are great differences in color quality and light intensity. When a LED is created it is first inspected for color and light quality and sorted(“binned”) into different categories. The best companies pay the most for high quality lights with only a slight color variation. The rest of the LEDs are not discarded but sold to inferior companies at much lower rates. These companies can then turn around and sell at much lower prices.
6) UL listed versus UL compliant. It is becoming increasingly common in the LED industry for companies to claim that their products are UL Compliant. What does this mean? It means that the product has not passed the testing of UL. A company can claim that it has followed the guidelines set forth by UL with regards to its products production and technical aspects. This in no way means it can pass the stringent tests put forth by UL. There is a great deal of difference between an LED that is “compliant ” and an LED that is listed by UL. One of the great difficulties buyers have is the fight against inferior cheap LEDs saturating the market. Many people are turned off of using LEDs after experiencing the poor products making this UL claim. Only UL Listed products have been tested and can bare the mark of UL. It is important to look for this marking on all LED products. It is also important to be sure that the mark is authentic.
7) Only purchase from a reputable company(preferably US). Check to see if the company has been around for at least 2 years. The internet is full of new companies that have purchased very cheap, low grade LEDs. These companies will offer very good warranties and very good prices knowing that they will selling under a new name the following year. An established company is are far more likely to actually back their warranties and work for repeat business.
8) Check for lumen output. Lumens represents the amount of light emitted by a light source i.e. how bright the light is. Realize that recommended light levels will vary based on the person and the task. When purchasing light bulbs, however, don’t assume that more watts means more light, more lumens means more light. CFLs start out with about 60 lumens per watt but average about 50 lumens per watt just to give you an idea.
9) Do not buy LEDs if your home or office is subject to known frequent voltage spikes. Unlike the CFL or incandescent light a voltage spike(actually energy spike) can “fry” an LED very easily. This is not considered a manufacturers defect and is never covered by any warranty. You may be unaware of voltage spikes and they may occur in seemingly random areas of your home or office.
10) Know where the heat goes! This may be one of the most important tips you can read. Excessive heat buildup is the leading cause of failure in all high powered LED lights. As stated above these LEDs need some way to dissipate the heat they produce and this is done through a heat sink. Almost every manufacturer has their own version of a heat sink. Because of this, heat sinks can vary greatly with some being so elaborate and large that it is obvious that they cannot be sold separately but must come as part of a unit.
If you are thinking of purchasing an LED par light that does not have an obvious heat sink you are going down one of three paths: 1)The par light is what is called low power and will not produce much light,2) the par is high power but will not last very long(unless the ambient temp is very cold) and 3) the par has a fan built into its base. The fans in the par bulbs are the same as those used in IBM laptop computers and are rated for 70,000 hours.
Author Bio: Peter Meredith is vice president of sales and marketing of Light Energy Designs. Five years of complete immersion in the world LED light bulbs has given him an insider’s view of this new and ever changing technology. To see the latest in LED lights go to www.lightenergydesigns.com
Category: Home Management
Keywords: LED lighting, energy efficient leds, led par light