Republication of Postings from the U.S. Department of Energy (DOE) Solid-State Lighting Program
by Jim Brodrick, U.S. Department of Energy
In the world of SSL, the unsung heroes who develop the standards and test methods that consistently characterize product performance and ensure safety have been at it for nearly a decade, under the auspices of such organizations as the Illuminating Engineering Society (IES), the American National Standard Lighting Group (ANSLG), the National Institute of Standards and Technology, the National Electrical Manufacturers Association (NEMA), Underwriters Laboratories (UL), the International Commission on Illumination, and the International Electrotechnical Commission. Thanks to them, we now have such basic standards and methods as IES LM-79 for the electrical and photometric measurement of SSL products, IES LM-80 for measuring lumen maintenance of LED light sources, IES TM-21 for projecting long-term lumen maintenance of LED light sources, and NEMA SSL-1 for characterizing LED drivers.
Their work is far from over, but with the basics fairly well-covered by now, standards and test methods are becoming more focused on specific product types and characteristics, spreading into various “nooks and crannies” to better meet users’ needs. For example, earlier this year we saw the publication of NEMA SSL 7A-2013, “Phase-Cut Dimming for Solid-State Lighting: Basic Compatibility,” which addresses a key issue for SSL. SSL 7A provides compatibility requirements for the use of dimmable LED products and forward phase-cut dimmers, which are by far the most commonly used dimmers. Intended to be used to design and qualify new dimmer and LED product combinations, it covers a range of supply voltages and frequencies, making it suitable for any lighting product type or application. Future dimming standards will cover other dimmer types.
A number of other key standards and test methods are still in development. One of these is IES TM-28, “Prediction of Lumen Maintenance of LED Lamps and Luminaires,” which is comparable to TM-21 but at a fixture level and is intended to lighten the testing burden on manufacturers by enabling them to use LM-80 data from the LEDs to help predict the lumen maintenance of complete lamps and luminaires. Another is ANSLG/ANSI C82.XX1, “LED Drivers Reliability,” which helps address the reliability of the key driver element in a lamp or luminaire. Still another is a revision of UL 1598C, “Light-Emitting Diode (LED) Retrofit Luminaire Conversion Kits,” a product safety standard that addresses LED linear replacement lamps.
Even though the standards folks do their best to produce effective standards and methods that are needed for the characterization of the technology, there’s always the potential for mismatches between these and the real-world situations for which they’re ultimately intended. That’s why it’s important for users and developers to communicate at some level, to ensure that standards and test methods are not only effective, but are also useful and application-friendly. To help that process, DOE — which works closely with standards-setting organizations and offers technical assistance and support — has lately been reaching out to lighting designers and representatives from utility programs, obtaining their valuable input through surveys and in person at our annual CALiPER standards roundtables, the most recent of which was held in April. These roundtables are also attended by standards-setting organizations and are intended to help ensure that their efforts effectively address the industry’s needs.
Standards and test methods may not be glamorous, but they’re essential for the success of any technology, and SSL is no exception. To learn more about standards development for solid-state lighting, visit www.ssl.energy.gov/standards.html.
