Fire hazard causes recall for Eco-Story LED lamps

25 Jan 2011
A US-based supplier has recalled around 42,000 LED lamps that can pose a fire hazard when used without a class II transformer.
Eco-Story, an LED lamp supplier based in Portland, Maine, has released a recall alert for LED lamps in cooperation with the US Consumer Product Safety Commission (CPSC).
The product-safety recall is due to a fire hazard and affects about 42,000 units. The recall was voluntarily conducted by the firm in cooperation with the CPSC.

When used without a Class II transformer, the LED lamps in question can overheat, posing a fire hazard. The CPSC said that the company has received two reports of overheated lamps. No injuries have been reported.
The recall involves 12-volt LED lamps with UL number E316865. The UL number is found on a label located at the base of each lamp.

Manufactured in China, the lamps have been sold to commercial locations, primarily restaurants, from December 2007 through August 2010, for between $19 and $45. The lamps were not sold directly to consumers.

The CPSC says that commercial locations should stop using this lamp immediately and contact Eco-Story for a free replacement lamp which does not require a Class II transformer. The company has contacted all known commercial locations that purchased this lamp.

About the Author
Tim Whitaker is the Editor of LEDs Magazine.

Green Bay Supports the Packers with Lighting up the Capitol dome

You just have to respect the environment in Green Bay, Wisconsin. Without the luxury of having color changing LED lighting, the state workers go “old school” with lighting up the Capitol Dome. The Dome has the Packers green and gold this week in honor of the football team making it to the Super Bowl.

Led by state worker Carolyn Trumpy (known as “the goddess of light”), lighting expert John Hyatt and colleague Jen Ahlstrom transformed the domes normal white illumination to the Packers team colors. The 48 HID flood lighting fixtures were covered by colored gel a material. Total cost to the state for the weeks lighting upgrade….just $1,800. Nice job guys!

MSi comes strong with the iMR-16

MSi has come to market with yet another phenomenal product to replace your traditional 35w Halogen MR16. The iMR-16 kicks out 400 lumens, has variety of color temperatures and beam angles, and is fully dimmable!

Efficiency

The iMR-16 requires only 8 watts to operate.  Led technology saves up to 80% of the light energy cost of a current Halogen MR-16.

Reliability

Designed and built with the highest level of components available today, including industry leading CREE LED’s, this UL approved product is produced in a world class manufacturing environment to the highest level of quality standards to assure a minimum of 50,000 hour bulb life, more than 20 times the life of standard Halogen bulbs.

Thermal Management

A hidden advantage of this bulb is its highly efficient thermal management system.

Worldwide Installation

The iMR-16 LED bulb has been designed as a 12 volt product allowing this product to be installed in virtually any country in the world!

Dimmable LED

Another key advantage of the iMR-16 program is its ability to dim throughout the power range with virtually any dimmer on the market today!

Beam color and angles

Designed for accent lighting applications the iMR-16 is available in 2700, 3000 and 4300 Kelvin and comes in a variety of beam angles including a 11.5, 16, 22, and 30 degree.  In addition, each bulb optic has been designed to provide superior beam conformation, peripheral lighting and intense Center Beam saturation to create a truly superior high powered accent light as well as room filling lighting coverage.

MSi has brought yet another high quality LED replacement lamp to market.  Their iMR-16 kicks out 400 lumens and is fully dimmable!  Finally, a the output needed to replace a 35w Halogen MR16.

For Pricing & Availability

Lusio® Solid State Lighting Reshapes Commercial and Industrial Market with Significant Release of 80 Fixtures Backed by 7-Year Warranties

Innovative high bay, low bay, and aisle lighting fixtures deliver solid lumen performance with precise optics, low operating temperatures and superior energy efficiency with LUXEON LEDs

Made in the USA, Lusio fixtures use housings comprised of up to 80 percent recycled aluminum and are designed to meet the rigorous physical demands and light level requirements of commercial and industrial lighting applications. Features and benefits include:

• Precise Optics: Lusio fixtures are engineered with optical reflectors that deliver five lighting distributions in mounting heights from 12-60 feet (3.5-18 m). The specially engineered reflectors also minimize glare and deliver a substantially higher percentage of usable footcandles on key work areas than traditional HID and fluorescent fixtures.
• Energy Efficiency and Low Maintenance: Lusio fixtures offer 35-70% energy savings through a direct replacement of HID and fluorescent fixtures. Because Lusio fixtures do not contain mercury or other hazardous substances, additional savings are achieved by elimination of costs for mercury lamp disposal. Lusio fixtures have an impressive overall fixture efficacy between 70 and 90 lumens per watt based on various fixture types and can generate more than 14,000 lumens for illumination of large retail, commercial, and industrial facilities.
• Thermal Efficiency: Lusio fixtures are one of the coolest operating commercial and industrial fixtures available in the market. The combination of specially engineered heat sinks and dissipation techniques, thermal transfer technologies and the superior thermal junction (Tj) temperature rating of 150°F (60° C) of the LUXEON Rebel ES LEDs used in the fixtures, allow Lusio to achieve up to 140° F (60° C) environmental operating temperature approval ratings by UL/CE. The overall cool fixture operating temperature of Lusio not only increases the longevity and reliability of the fixture, but also decreases AC cooling energy costs as compared to typical HID and high-output fluorescent fixtures.
• Controllable: Lusio fixtures interface to standard 0-10v dimmers and are offered with occupancy sensors to further reduce their energy costs.
• 7-Year Warranties: Lusio fixtures come with a standard 7-year replacement warranty. Full terms and warranty details are available at www.LusioLighting.com.
• Made in the USA: Lusio fixtures are compliant with the Buy American Act and the “Made in the USA” statement as described by the Federal Trade Commission. Lusio Solid-State Lighting, as a division of LightWild, is an S.B.A. designated federal contractor (LightWild, L.C. – DUNS No. 360795368).

Lusio Leverages Industry Leading LUXEON Rebel ES from Philips Lumileds

Lusio Solid-State Lighting selected the LUXEON Rebel ES for use in its fixtures after extensive analyses of several LED packages.

“While many manufacturers seem to be chasing lumens as the sole criteria for LED selection, LightWild also considered many other factors,” Stafford said. “We believe that the Rebel ES will deliver super-long life stability and performance value for our customers.”

“LightWild looked for a solution to meet their objectives for superior light output, efficacy, and quality of light, each of which is delivered by LUXEON Rebel ES,” said Steve Barlow, Executive Vice President of Sales and Marketing at Philips Lumileds. “We are proud that they have chosen the LUXEON Rebel ES for their Lusio product line.”

Models

Each distribution is available in a 2×2 model (81 LEDs) or 1×4 model (54 LEDs).

 

Environments

Lusio is constructed with various environmental conditions in mind. The Open fixture design is UL dry/damp location listed while the Lusio Enclosed fixtures are UL wet location listed (IP65).

Light Output

Lusio fixtures can deliver more than 14,000 lumens and 90 lumens per watt to fit various lighting and energy needs. Check our photometric and IES files for more information on the light output of each option.

LED Color

Lusio fixtures are offererd in two color temperatures, a Neutral White 4000K (nominal) and a Cool White 5700K (nominal). Lusio fixtures use LUXEON Rebel ES LEDs exclusively and are selected through Philips Lumileds stringent binning procedures to ensure color consistency within each fixture and from fixture to fixture.

Mounting Options

Each Lusio model can be installed with suspension cables or surface mount brackets provided. Both options include all necessary hardware and are easily installed in the field.

For Pricing & Availability

Panasonic EVERLEDS LED Bulbs with Wide Light Distribution Angle

Panasonic will release EVERLEDS LED bulbs featuring the wide light distribution angle*1 of approximately 300 degrees, which is almost equivalent to the angle of traditional incandescent lamps, on March 18, 2011 in Japan.

 Consumers have become increasingly conscious of energy conservation at home, including lighting. LED bulbs are quickly finding their way into homes thanks to their high energy efficiency and long life. However, applications of existing LED bulbs*2 are limited to illuminating spots beneath the lamps because of the bulbs’ narrower light dispersion than incandescent bulbs. 

Panasonic’s new LED bulbs have responded demands for wide light distribution angle with the two key technologies: “optical design technology that spreads light using a combination of LED packages arranged in a circular pattern inside a large globe and a double reflector structure” and a “high heat dissipation technology with the circuit arranged above the LED packages in order for the circuit parts to be away from the body where the heat converges.”

 

 

Light Diffusion Comparison

Internal structure of LED bulbs (LED package arrangement)

LED Structure

Internal structure of LED bulbs
(Comparison of LED package and electronic circuit arrangements)



With the new Panasonic LED bulbs, you can replace incandescent bulbs used in light fixtures that help disperse the light throughout the room, giving lighting effects with a light distribution angle almost equal to incandescent light bulbs.

The new E-26 base LED bulbs come in two colors, warm lamp color (LDA7L-G) and daylight color (LDA7D-G) which has brightness equivalent to a 40W*3 incandescent lamp and boast a long service life of 40,000 hours.*4

Panasonic will strengthen its product lineup with these new bulbs and meet a diverse range of needs to further promote the replacement of traditional incandescent lamps.*5

Notes:
*1. A value consistent with the definition of “beam spread” in the Japan Industrial Standards JIS Z8113 “Lighting vocabulary,” and “luminous intensity distribution angle” specified in the Japan Electric Lamp Manufacturers Association Standards JEL 800 “LED Light Bulb Type Code Assignment Method,” in comparison with Silica bulbs
*2. Panasonic LED bulbs, including LDA7L-A1
*3. Indication of the brightness in accordance with the “LED Light Bulb Performance Indication Guidelines 008” issued by the Japan Electric Lamp Manufacturers Association. Comparison between LDA7D-G and the 40-W tungsten filament lamp for general lighting purposes specified in the Japan Industrial Standards JIS C7501 “tungsten filament lamps for general lighting purposes.”
*4. The rated life is the number of hours of use until the total luminous flux (brightness) becomes 70% of the initial value. The rated life shows an average value and is not guaranteed.
*5. With some fixture types, the lighting performance may not be equivalent to that of incandescent lamps. If the clearance between the LED bulb and the shade of the lighting fixture is narrow, the area around the base may look dark. These LED bulbs cannot be used for fixtures with a dimmer function.

Voiding defects: New technique makes LED lighting more efficient

Light-emitting diodes (LEDs) are an increasingly popular technology for use in energy-efficient  lighting. Researchers from North Carolina State University have now developed a new technique that reduces defects in the gallium nitride (GaN) films used to create LEDs, making them more efficient.

LED lighting relies on GaN thin films to create the diode structure that produces light. The new technique reduces the number of defects in those films by two to three orders of magnitude. “This improves the quality of the material that emits light,” says Dr. Salah Bedair, a professor of electrical and computer engineering at NC State and co-author, with NC State materials science professor Nadia El-Masry, of a paper describing the research. “So, for a given input of electrical power, the output of light can be increased by a factor of two — which is very big.” This is particularly true for low electrical power input and for LEDs emitting in the ultraviolet range.

The researchers started with a GaN film that was two microns, or two millionths of a meter, thick and embedded half of that thickness with large voids — empty spaces that were one to two microns long and 0.25 microns in diameter. The researchers found that defects in the film were drawn to the voids and became trapped — leaving the portions of the film above the voids with far fewer defects.

Defects are slight dislocations in the crystalline structure of the GaN films. These dislocations run through the material until they reach the surface. By placing voids in the film, the researchers effectively placed a “surface” in the middle of the material, preventing the defects from traveling through the rest of the film.

The voids make an impressive difference.

“Without voids, the GaN films have approximately 1010 defects per square centimeter,” Bedair says. “With the voids, they have 107 defects. This technique would add an extra step to the manufacturing process for LEDs, but it would result in higher quality, more efficient LEDs.”

The paper, “Embedded voids approach for low defect density in epitaxial GaN films,” was published online Jan. 17 by Applied Physics Letters. The paper was co-authored by Bedair; Pavel Frajtag, a Ph.D. student at NC State; Dr. Nadia El-Masry, a professor of material science and engineering at NC State; and Dr. N. Nepal, a former post-doctoral researcher at NC State now working at the Naval Research Laboratory. The research was funded by the U.S. Army Research Office.

Source: ScienceBlog.com

Vu1 Brings a New Light with Electron Stimulated Luminescene

Electron Stimulated Luminescence™ Lighting Technology

Overview

Electron Stimulated Luminescence™ (ESL) Lighting Technology is an entirely new, energy efficient lighting technology. It uses accelerated electrons to stimulate phosphor to create light, making the surface of the bulb “glow”.  ESL technology creates the same light quality as an incandescent but is up to 70% more energy efficient, lasting up to 5  times longer than incandescent and contributing to the reduction of greenhouse gas emissions. There is no use of the neurotoxin Mercury (Hg) in the lighting process.

With this technology, Vu1 has developed its first light bulb that received UL certification in October 2010: the R30 ESL bulb, a direct replacement for the 65W incandescent flood bulb which is virtually indistinguishable from this traditional lamp it replaces and, unlike CFLs, is mercury-free.

In addition to the R30, the company is currently developing a variety of highly energy efficient, optimal light quality mercury-free light bulbs. In 2011 and 2012, Vu1 plans to introduce the classic A-type lamp for US and European consumers, the R40 for the US commercial market and the R25 in Europe.

Proven & Safe

In creating ESL Technology, Vu1 merged several existing and proven technologies then uniquely adapted them for “lighting”. The company uses commonly sourced, non-hazardous, commercial materials that are customized to our specifications.

Safe as a lighting source, the ESL technology fits neatly into classic light bulb shapes similar to those familiar to consumers everywhere. This eliminates the need to bend the technology into an unusual, twisted spiral shape (CFL) or have costly and heavy heat dissipation designed into the bulb housing (LED).

Key features of the technology and associated manufacturing processes are patent pending.

Manufacturing

Vu1 operates a wholly-owned manufacturing subsidiary, Sendio s.r.o., in the Czech Republic. This enables the company to manufacture its products directly to protect the company’s intellectual property while maintaining close control over the quality, volume and distribution of initial product production.

The 75,000 square foot facility provides Vu1 with scalable production capability. The site’s initial production capacity is up to 6.8 million bulbs annually with a planned future capacity of 30 million bulbs annually. Vu1 employs a highly skilled team that has been trained at leading manufacturers such as Philips and Sony. The facility is centrally located, enabling efficient worldwide distribution.

Light Bulb Technology Comparison

With its ESL technology, Vu1 can produce light bulbs that have all the benefits of today’s energy efficient bulbs but add the distinct features that consumers and businesses want.

• Energy Efficient– Vu1 bulbs are up to 70% more efficient than the incandescent bulb
• Superior Light Quality – Unlike CFL or LED bulbs, ESL technology features qualities consumers enjoy now – a perfect light quality that turns on instantly and is fully dimmable
• Mercury Free – Vu1 bulbs contain no mercury, allowing them to be household disposable and safe to recycle
• Affordable – ESL technology adapts to existing light bulb shape, reducing production costs and providing consumers and businesses with a competitive and cost-effective solution
• All of Vu1’s bulbs will be UL approved and in the future ENERGY STAR® compliant.
• Smaller Carbon Footprint – Bulbs generated by ESL technology have a smaller carbon footprint throughout their lifecycles than those generated by LED and CFL technology
• Lower Production Costs – ESL bulbs have lower manufacturing and disposal costs compared to LED and CFL bulbs

GreenSpace: The new lightbulbs, confusing but enlightening

By Sandy Bauers

Inquirer GreenSpace Columnist

Lighting is changing fast. Incandescents as we know them are on the way out.

It may be confusing for a while. But in the end, your wallet will thank you. And so will the planet.

Walk down today’s lighting aisle, and it’s intimidating.

Incandescents. Halogens. CFLs. LEDs. All sizes. All shapes. All colors, from warm white to a crisp bluish tint. And more to come.

So read on for a tour of the ever-burgeoning bulb-land.

“There’s a tremendous amount of development,” said Brian Fortenbery, an energy efficiency lighting expert with the Electric Power Research Institute, a national nonprofit. “It’s not a one-technology game, by any stretch.”

Driving the change is a provision in the Energy Independence and Security Act that Congress passed in 2007, during the George W. Bush administration.

It set energy efficiency standards for lightbulbs, which will begin to phase in come Jan. 1, 2012.

A wide misconception is that the law “bans” incandescents and “mandates” CFLs.

It’s more of a required tune-up, supporters say. The act requires new bulbs to put out the same light with 30 percent less energy.

But in reality, incandescents as we know them will not meet the standard.

Recently, some influential critics have surfaced. U.S. Rep. Joe Barton (R., Texas) and a dozen other Republicans introduced legislation they’re calling the BULB Act, for Better Use of Light Bulbs. It would repeal the bulb portion of the 2007 act.

“It is about personal freedom,” Barton said. “These are the kinds of regulations that make American people roll their eyes.”

The energy efficiency community is aghast. Isn’t conservation part of being a conservative?

With about four billion screw-based sockets to fill in the United States, it matters what we put in them. Lighting accounts for about 15 percent of the energy use of a typical household.

Efficiency advocates say the new standards ultimately will save consumers more than $10 billion annually – $143 per household – and avert the need for 30 new power plants.

They point out the act isn’t telling people what kinds of bulbs to put in their homes. It’s more like increasing the gas mileage of cars.

Moreover, the market is already responding. At the beginning of January, Ikea stopped selling incandescents altogether.

The energy efficiency world has taken on our fridges, our water heaters, our washers and dryers. But the incandescent lightbulb has remained “the least efficient piece of equipment in our homes,” said Noah Horowitz, a lighting expert with the Natural Resources Defense Council, a national nonprofit.

Ninety percent of the electricity that goes into it is given off as waste heat. “Tell me another product where you’re only getting 10 percent of the energy coming in converted to useful work,” he said.

For those who can’t quite kick the habit of energy-guzzling incandescents, halogens may be your first baby step toward efficiency.

Adding the gas reverses the deterioration of the tungsten lighting filament, making the bulb about 25 percent more efficient. Otherwise, these bulbs look and act like incandescent twins.

The next step in efficiency is CFLs, compact fluorescent lightbulbs. These have had a tough go since their introduction a few decades ago, when they were big and clunky, with poor light that didn’t even come on right away. And they were expensive to boot.

Now they are cheaper, brighter, and truer, the shades of light ranging from warm white to cool. New versions are dimmable.

Most still take a few minutes to reach full brightness, but General Electric has announced a halogen “hybrid” that is instantly bright. It’s due on shelves this spring.

One persistent problem, at least in terms of public acceptance, has been the mercury in CFLs, although the amounts have lessened significantly. People read the Environmental Protection Agency’s instructions for cleaning up a broken bulb – air the room for 15 minutes, don’t vacuum the pieces – and they freak.

All fluorescent bulbs, not just CFLs, have mercury. It’s what Michael Myer, a lighting engineer with the U.S. Department of Energy’s Pacific Northwest National Laboratory, calls “a necessary evil.”

But we can’t ignore the mercury that is produced in a coal-fired power plant, which accounts for roughly 50 percent of the nation’s power. Scientists have compared the mercury emission that incandescent bulbs would be “responsible” for to the mercury in CFLs, and declared the CFL the better choice.

Many big-box home stores offer recycling, so the mercury is handled properly.

Engineers and first-adopters are excited now about LEDs, which hold the promise of huge efficiencies.

For now, the technology is deemed to be in the toddler stage. Or the equivalent of cell phones in about 1990, when they were like bricks you held to your ear.

So they’re heavy, the light’s dim, and some are infused with the color blue.

But in recent months, bulb giants Philips Lighting North America and Osram Sylvania have released 60-watt equivalents with a warm hue and in the traditional shape of an incandescent. (The external ribs on many LEDs carry heat away from the bulb.)

Myer credits the Department of Energy’s “L Prize,” which will be awarded to the first LED that has the same light output as a 60-watt incandescent and meets other standards. So far, Philips is the only entrant.

Sylvania’s LED retrofit market manager, Ellen Sizemore, said the company was more interested in “providing the market with the best, most cost-efficient products for the masses” rather than some of the finer points of the L Prize.

So far, the price is an eye-opener – about $40 per bulb. But Peter Soares, Philips’ consumer marketing director, said the bulb would save $142 over its life for someone paying 11 cents a kilowatt-hour.

We may yet see all kinds of new technologies, experts say.

One of many newcomers is the “electron stimulated luminescence” bulb sold only online and developed by the New York company Vu1.

Certified by Underwriters Laboratories in October, it uses the technology of old TVs. A cathode generates electrons and sprays them onto the bulb’s interior phosphor coating. The equivalent of a 65-watt incandescent, it costs under $20 and uses just 19.5 watts.

Clearly, however, old habits die hard. Sales figures from the industry group the National Electrical Manufacturers Association show incandescents still clearly in the lead. CFLs, the second-runners, account for only one in four bulb sales.

Still, in 2010, 60 percent of respondents to a national “socket survey” commissioned by Sylvania said they had switched at least one bulb to a more energy-efficient version in the last year.

But respondents ranked the amount of energy the lightbulb uses only as fourth most important on a list of attributes.

So wake up, kiddos.

The bulbs aren’t the be-all.

The lingo is changing, too.

Watts are on the way out. Eventually, we’ll all have to learn lumen-speak.

Lumens are a measure of brightness.

Watts are simply the power needed to light the bulb, which worked as a proxy when we had only one kind of bulb. But now you can get an LED bulb that’s as bright as a 60-watter but consumes only 12 watts.

New labels are headed our way, probably this summer, designed by the Federal Trade Commission.

They’ll resemble food nutrition labeling, showing how bright the bulb is, its expected life, its light appearance, the energy used, and the estimated yearly energy cost.

Advocates like the NRDC’s Horowitz say the best is ahead, both in light and in savings.

“Today’s consumers have no idea what a bad deal that 25-cent 100-watt incandescent bulb was,” he said.

Specifying LEDs in lighting design

Specifying engineers and lighting designers need to understand more about LEDs and the ways information is presented so we can provide clients with the best lighting options.
Joseph M. “Jody” Good III, LC, IALD, Spectrum Engineers, Salt Lake City

01/20/2011

There is a great deal of hype today about light-emitting diodes (LEDs) as a viable “near-perfect” source of light. LEDs are generally expected to last far longer than any conventional light source and be more energy-efficient. As a professional specifer, I hear the hype weekly, if not daily, and have a few findings and opinions that might help other specifiers understand what is going on, and where to look for reliable, current information.

Last year we relocated our own offices and have some personal experiences to share as a result. The lighting field is changing so fast that anything written is outdated before it is published, so please consult the references provided in this article to do your own investigation.

LED luminaires are built using single or multiple LEDs. Sometimes they are all on one assembly; other times individual chips are aggregated into larger assemblies and then used in a luminaire. This year I have specified luminaires with 1 to 170 individual LEDs. Performance of these LEDs has varied with Correlated Color Temperature (CCT) from warm at 2700 K to cool at 6500 K. Some dim, some don’t. Some are indoors, while others are outdoors. Understanding the lighting situation and the luminaires available is important from the lighting designer’s point of view.

Those of us old enough to remember the mass adoption of LEDs as indicator lights in the 1970s will recall the excitement when we saw blue LEDs. They were different, interesting, and far more expensive than the common red, amber, and green LEDs. We were quick to adopt these LEDs in exit signs, aisle lights, and traffic semaphores, for example. Little did we know that the blue LEDs were the innovation that would eventually lead to white LEDs and make LEDs feasible for general interior lighting. And the first “white” LED luminaires created the color white by mixing red, green, and blue LEDs to “make” a version of white light. This system is still used to get white lighting from LEDs, although it is not the most energy-efficient process, as we will discuss later.

LED performance

Red, green, and amber LEDs have a relatively long life, between 70,000 and 120,000 hours. In these applications, LED life is measured in mean time between failure (MTBF) while maintaining usable light output. While measured precisely in the lab, the resultant light and life in the “real world” was not much of a problem as most of these applications could add LEDs or adjust the current limiting resistors to achieve the required systemic light output. This worked fine for most LEDs used in indication situations.

However, this “bench rating” of LED output was problematic for white LEDs. The mounting and operational environment of LEDs for general lighting purposes was physically not as accommodating for this new application. The operating environment for LEDs in general lighting service was far from the ideal temperature on the development bench.

As a result, in 2006 the U.S. Department of Energy stated that current industry claims of efficacy (remember claims of 150 lumens/Watt?) were not reasonably attainable in the field and could not be used as the basis of rating LED performance in the lighting business. At the same time, the government said that the lighting industry had to develop testing procedures designed to guide everyone to a fair and useful methodology. As a result, specifiers should use only valid test claims from manufacturers that state specifically that the data was obtained by following one or both of the Illuminating Engineering Society (IES) standards, LM-79 and LM-80, created to address the needs of LED illumination manufacturers. There are specific testing and rating guidelines and, as this is written, more documents are under development.

The U.S. Dept. of Energy has established the Caliper Program, a testing program designed to assist users in evaluating LED technology in lighting applications. The program’s website contains interesting test reports and technical information on LEDs. The Caliper Program is also the sponsor of the “Lighting Facts” product label, which is a reliable badge of technical honor.

LM-80 establishes the method for calculating the rated life of an LED: determine the light output at a specific point in the life of the LED to identify and standardize the acknowledged “end of (useful) life.” This is known as L-70, or the point where the lumen output of the LED is at 70% of the initial light output. This end-of-life determination is necessary because LEDs have the same end-of-life property as mercury vapor lamps. That is, they don’t die; they simply continue to fade out. I tell my students that this reduces maintenance on many a barn light across this country, because the lamp does not fail per se, but it is little more than a green glow over the barn door after 40 years.

LEDs have this same problem. The limit of useful lighting has to be determined, and L-70 is the agreed specification. Specifiers need to understand the meaning of L-70 and base their project calculations on that understanding. I have seen manufacturers use other values, such as L-80 or L-50 for specific messages—that is, mean lighting level for interior luminaires for the L-80, and a claimed useful life for L-50. Unless product comparisons are made using the same reporting basis, however, the differing numbers could lead to a misunderstanding of performance.

While on the matter of specifications and calculations, the light output for all LED luminaires is measured by using “absolute” photometry, tested per LM-79. This is because the photometric performance of an LED luminaire is completely dependent on the composition of the specific LED engine. Most other luminaires are tested and legitimately report using “relative” photometry. This is useful in facilitating changing lamps in the same luminaire; for example, a compact fluorescent (CF) downlight can be simply recalculated changing the compact fluorescent lamp lumens with a high degree of accuracy. LEDs are not this flexible, so a photometric test must be run for each lamp assembly it will hold.

Individual performance reports

LEDs get some of their optical advantage by being natively directional. Therefore, each individual LED has a lens, reflector, prism, or other individual optical control device. This directionality is used in downlights (street and area lights, for example) to affect the overall luminaire performance. As a result, LEDs require clusters of optical controllers, not one reflector or lens over the whole assembly. If you look closely at LED luminaires, you will see the individual lenses or prisms. This works well, but we must remember to get the fixture-specific photometric file, and not “edit” the one we have. This applies to a previously interchangeable metric such as changing lamps to change color temperature, for as we will see, many LEDs have different light outputs that are variable dependent on color.

Remember to find the photometric performance file for the exact luminaire (or at least specific LED assembly) that you intend to use as your basis of design, and be careful in evaluating substitutes for compliance with your important project criteria.

There are a few LED assemblies that offer “lamp” interchangeability, but these are just coming on line. Today it is not easy to “change the lamp” as we are used to with other forms of lighting. I am confident that as the LED matures as a light source, it will restore some of this design and specification freedom. Stick with individual performance reports, using absolute photometry, and surprises and disappointments will be minimized.

LED color

How “white” LED light is made is interesting. We previously discussed the mixing of colored LEDs. RGB is the most basic technique, with amber sometimes added (RGBA), or even up to seven colors (ROYGBIV; look familiar?). The most common approach with individual LEDs is to use a blue LED and insert a yellow phosphor filter inside the package to create white light. The third method of creating white light using LEDs is to use blue or violet LEDs to excite a phosphor that is a part of the luminaire but separate from the LED that emits the white light. Each of these has advantages and disadvantages.

The advantage of mixing colored LEDs to achieve white light is the color flexibility and color effects that it allows as well as mixing to create white light. This is very effective in display and entertainment applications.

The yellow phosphor on a blue LED device is by far the most common white LED used today. Since there are many variables in the manufacture of these LEDs, they are individually rated for their performance by the LED manufacturer. They are sorted into “bins” following ANSI standard C78.377-2008 for determining the CCT of LEDs as devices. The light engine manufacturer can use closely “binned” LEDs and have more consistent color—at a higher cost—or accept (or use) a wider selection of LEDs from more bins and reduce the cost, balancing this with performance. Since it is more expensive to produce warmer LEDs, most applications that do not require warmer light (parking lots and roadways, for example) allow the use of visibly cooler LEDs to achieve lower product cost.

There is a human factor for this “bluer” light, however. As we age, the physiology of our eyes begins to scatter the blue wavelengths of light. In extreme cases this makes blue light appear glary. I have had clients select the orange light of high-pressure sodium lamps specifically because of their perceived comparative comfort, without glare. The optimum solution would be to use warmer LEDs in these applications, which will be more practical as the cost and performance of warmer LEDs draws closer to matching the performance of cooler LEDs. There is research that identifies an increase in human health issues associated with blue light in the sub-500 nm range (National Institutes of Health: Meeting Report: The Role of Environmental Lighting and Circadian Disruption in Cancer and Other Diseases-2007). The light from cool LEDs falls in this band. Specifiers might want to watch for developments in this area. For now, avoid using blue LEDs in night lights.

The third method of creating white light indirectly from LEDs using the separate phosphor technique has the advantage of more consistent light color creation that more closely follows conventional specification. The science of using phosphors to create visible light from nearly invisible energy is well known. Using this method is creative, effective, and comfortable for lamp manufacturers. There are inherent systemic inefficiencies in this method and some packaging and optical differences that need to be addressed. I have found the color advantages and the less “technical” appearance of this method to be worth the effort when considering white light in residential and many commercial applications. This method also requires continuous evaluation because it too might change with each product improvement.

There is a limited color-mixing technique used to create variable color temperature in the “white” range. This technique uses extremely warm “white” LEDs and extremely “cool” white LEDs and a dimming system to mix them to achieve almost continuous white light with a changeable CCT and variable overall intensity, near full-range dimming. This is useful where the room needs to dramatically change character. Examples include restaurants facilitating the breakfast rush as well as nightly dining or a retail paint sales department that benefits from making the whole area a “color box.”

The other metric used to evaluate light is known as the Color Rendering Index (CRI). Many LEDs have difficulty generating the red light wavelengths necessary to produce light equal to today’s tungsten-halogen sources. LED technology will undoubtedly continue to address this issue, which is one of the advantages of the improved phosphor method. The LED industry, particularly those from outside the lighting industry, have tried to raise the shortcomings of the CRI metric itself, saying it measures the wrong thing. The initial CRI metric was based on measured color performance on largely pastel colors, but now there is an expanded CRI color field that includes four more saturated colors. The current technical reference for color rendering that mentions performance on the “R9” color is directly referring to the light source’s ability to generate and therefore render red light for lighting the red in objects. Some manufacturers select LEDs from adjacent bins, favoring the warmer colors to emphasize the red spectrum. This represents care and a concern for a high level of performance. Other manufacturers allow wider tolerance of LED color, perhaps alternating warmer and cooler LEDs in adjacent positions in the luminaire. In my opinion, this technique was acceptable, even creative, when the cost and availability of tighter performance LEDs were more difficult to achieve, but this is neither needed nor acceptable today. Specifiers must still be sure the manufacturer’s tolerance for color variability will not be seen in the application. Coves and indirect lighting situations come to mind, where there is a chance to see a considerable number of lights at once. Care must be taken to ensure these light sources match as expected when installed.

LED efficacy and droop

The efficacy of these cooler chips is higher than the warmer colors, so there really is more light (lumens)/Watt of electricity consumed. This improved efficacy at the blue color can be used to compare many LED lighting proposals, comparing metal halide to LED for example. Remember, because there is a difference in the light output or the electrical wattage consumed, even changing by color, the full picture must be considered when comparing possible lighting systems. There is a misconception in many quarters that light sources can be compared and selected based on CRI alone. In fact, CRI is only appropriate as a comparison metric between light sources of the same CCT. It will help you keep manufacturers’ claims and your requirements clear in your mind.

Based on today’s LED technology, there are reasons to think that we have nearly reached the technical limits of the amount of useful light that can be created by any single LED chip. There is an excellent discussion on LED “droop” in the August 2009 issue of IEEE Spectrum magazine. Given this limitation, we must look to the pure research labs to resolve this problem. Meanwhile, we are solving our need for more quality light from LEDs by getting larger and larger luminaires.

LED power supply

The next issue to consider is the power supply or LED “driver.” The specifer rarely creates a specification for the power supply; it is selected by the luminaire manufacturer. The specifer should be certain the LED array and the power supply are suitable for the project and compatible with the project lighting control system. Until very recently, there has been little improvement on power supplies for LED luminaires. Since the LED array itself was created by electronic engineers, the power supply was developed alongside the LED, and frankly, it was an easy undertaking for these engineers. However, this process caused a delay in the development of more universal or standardized LED arrays and power supplies. This is changing. Today more LED luminaires are being developed using standardized drivers. In fixed light scenarios, where dimming is not required, improvements to these drivers are leading to reduced line Wattage. In time, more efficient power supplies will become common.

In three-color mixing systems, each of the colors has to be dimmed to mix colors, requiring variable individual power supplies. More line Watts are consumed to drive the LED as compared to the lowest approach, fixed individual power supplies. Therefore, lower line Watts are possible using single LEDs in general applications.

The LED power supply that dims can have any of the three common control techniques (forward or reverse line voltage, phase control, or 0 to 10 Vdc control) depending on the particular driver. Specifiers must pay special attention to these details as some manufacturers have recently adopted third-party LED drivers and changed existing products without much notice.

Other considerations

Today’s ceilings and light poles can handle larger luminaires. Luminaires with larger masses of LEDs require better thermal management as a part of the luminaire design, whether the luminaire is in a plenum or on an outdoor pole. Very few conditions will diminish the performance of lamps in general, and LEDs in particular, more than heat will. Once the issue of recognizing the plenum as the customary location for LEDs in interior lighting situations was resolved, luminaire manufacturers addressed the critical need for thermal management at the LED. As designs evolve, watch for thermal management to become a center of improvement. Be very aware of your intended ambient temperature at the location the fixture is installed.

When LEDs are dimmed, there is not the customary color shift toward warm as seen with tungsten-halogen dimming. In fact, the opposite may be true depending on the amount of dimming and method used to generate the red light energy. This cool shift may or may not be very pronounced.

The last issue specifiers need to be aware of is emergency operation of LED luminaires. Until now, there was little standardization of the power supply. In my own offices, we circuited together the emergency LED luminaires as planned. We ran them together through their control groups and attached them to a consolidated battery inverter. There are a few commercial battery inverters available similar to the ones we are used to seeing in the CF world. While this field will standardize in the future, care is particularly necessary today in selecting the method of powering emergency LED luminaires.

Careful selection

Specifiers must be very careful in selecting and approving LED light sources from a color and CRI perspective. The pressure will be present to select the cooler colors, probably more cool than the specifier is accustomed to. If high color reproduction is needed, insist on LEDs with sufficient red light energy. Be aware of energy claims and the specification of the power supply (check things like harmonics). If dimming is desired, compatibility with the control system must be coordinated. The cost of the LEDs is up to 40% of the actual cost of the luminaire, so selecting luminaires that tightly select the LEDs they use is generally worth it. Ask about the manufacturer’s binning specification. Careful manufacturers will know (and be proud of) their tight binning.

Some semiconductor companies in the LED lighting business are not as attuned to all the human needs of lighting and are learning about the need for improved CRI, for example. Yet these are the very companies that will overcome the light output or droop problems. Meanwhile, the standardization of the LED driver features will lead to improved electrical efficiency and advances in dimming and staged switching. Because this is truly a technology in its infancy, and manufacturers are “improving” their products constantly, specifiers need to exercise extra care in the products they consider for their projects.

In summary, specifiers need to understand more about LEDs and the ways information is presented for our consideration. Part of this is due to the way various manufacturers report their performance, and part of this is due to the rapid changes in this exciting field. Specifiers will always do the best they can for their clients, but two challenges remain: separating the truth from fiction and knowing the important criteria and features for each project.

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– Good, LC, IALD, FIES, USITT, LEED AP, has a bachelor’s degree in lighting and theatre design from the North Carolina School of the Arts and has more than 30 years of experience in lighting and theater design. He is a principal for Salt Lake City-based Spectrum Engineers where he designs high-performance lighting systems featuring sustainable solutions. Good is a member of the International Assn. of Lighting Designers (IALD) and the U.S. Institute of Theatre Technology (USITT).

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Lighting Draws In New York Jets Plane Close to the Empire State Building

The Jets were in an Empire State of Mind Sunday night after toppling the New England Patriots.

As the team’s charter flight descended toward Newark Airport, the captain called an audible and asked the tower for permission to veer closer to the Empire State Building, which was lit up in the team’s colors.

“Well I’ve had an unusual request,” the captain said. “If it’s green and white, these guys actually want to get as close as we could to see it.”

Like an airborne offensive line, Newark’s air-traffic controllers gladly cleared a path for the plane.

“You guys are awesome,” the captain said. “And I will tell you later who said that.”

According to team sources, he was relaying a message from boisterous head coach Rex Ryan.

Jets GM Mike Tannenbaum said it was a fitting end to a perfect night. “For the Empire State Building to be lit green and white was already special,” he said. “Then for everyone involved to allow us to have a view on our way back was a great ending for our trip and something that the team will always remember.”

The route change that brought the Boeing 767 within clear view of the building required special permission to stray into La Guardia’s airspace, FAA spokesman Jim Peters said, but “no other flights were affected.”

The tower later alerted the jet as it neared the city’s tallest building.

“Taking you down the west side of the building down the Hudson,” the controller said. “Empire State Building should be at 11 o’clock.”

“It’s beautiful,” the flight captain said. “Yeah, we’ve got 200 people looking at it. A beautiful night for it, too. Really appreciate it, guys.”

Controllers then directed Continental charter flight 1915 toward Newark, where the plane landed at 10:53 p.m.

“Glad to do it,” the tower said.

Moments later, the tower said, “Clear to land for the champion New York Jets.”

Asked if they enjoyed the fly-by, the captain said, “We did, and the team did, too. It was great. I know the coach liked it.”

Such a fly-by request is not uncommon, but in this instance was particularly special for the controllers.

“It’s kind of cool,” said Ray Adams, president of the National Air Traffic Controllers Association at Newark. “It wasn’t a typical flight path, but it does happen,” he said.

jeremy.olshan@nypost.com