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Line-Voltage Socket Design Competition

Line-voltage Socket Design Competition

The U.S. Environmental Protection Agency (EPA) and the American Lighting Association (ALA) want to make it easier for consumers to use energy-efficient residential light fixtures. Replaceable electronic ballasts for ENERGY STAR® residential lighting fixtures are becoming more popular due to increasing demand from utilities, builders, and other market actors, as well as the need to provide this convenience for consumers. Currently, there is no design standard for line-voltage sockets (i.e. what the replaceable ballast plugs into). The lack of a standard line-voltage socket, and thus a lack of a standard pin base on the replaceable ballasts, is a barrier to ballast interchangeability.

With that in mind, the U.S. EPA asked the Lighting Research Center (LRC) to hold a round table, bringing together fixture and ballast manufacturers to discuss and determine a standard pin-base configuration and to identify next steps. On June 24, 2004 the LRC held the round table. The participants agreed to organize a design competition to select one standard line-voltage socket and ballast holder that would accept replaceable ballasts from different manufacturers within a category of luminaires.

Manufacturers were invited during the summer to compete with innovative line-voltage socket designs suitable for residential luminaires of 26 watts or less, including floor and table lamps, wall fixtures, chandeliers, and ceiling fans. The standardization effort underway does not focus on the ballast itself, what is inside, or who makes it. Rather, we are simply trying to standardize the "socket" - that is - the base of the pop out ballast where it connects to the 120V supply. As a condition of entry, the winning socket design must maintain an open protocol and be made available to the public after the competition without any royalties.

In October 2004, entries were reviewed by an evaluation panel composed of representatives from luminaire, ballast, and lamp manufacturers, energy efficiency organizations, the ALA, and the LRC. The best line-voltage socket and ballast base design for compact fluorescent lamp (CFL) fixtures was selected and drawings of the winning design are available below. This winning entry eventually will become a design standard for CFL line-voltage sockets used in ENERGY STAR® qualified luminaires, making it easier for consumers to purchase replacement ballasts for their home lighting. ENERGY STAR is a government-based program helping businesses and individuals protect the environment by using energy-efficient products.

The evaluation committee submitted its recommended design to ALA and U.S. EPA. The U.S. EPA and the LRC are working with the ALA, market transformation groups, retailers, trade associations, socket and ballast manufacturers to encourage universal acceptance of the recommended design. Manufacturers, such as Technical Consumer Products (TCP) and Rhine Electronic Co., Ltd. are already working on manufacturing the recommended design. The long-term goal is to build the standard socket into the ENERGY STAR fixtures specification as a program requirement.

The drawings of the recommended design are available below. Please note that, although the replaceable ballast is included in the drawings, it is NOT part of the design recommended by EPA. The recommended design is for the line voltage socket ONLY.

During the upcoming year EPA will formalize the design and will include it as a requirement in the residential light fixtures specification, Version 4.0 for fixtures that use removable ballasts that are 26 watts or less. EPA has no plans to make this removable ballast a requirement for all fixtures, only those that already use this type of line voltage connection. For technical questions regarding design specifications, please e-mail Jasper Chua (Viva Lighting) at The manufacturer agreed to have the line voltage socket design available for public use, on an open protocol and on a royalty free basis. Authorization letter

For questions regarding the line-voltage socket competition please email Mariana Figueiro or Peter Banwell at

The drawings of the recommended design are available below.

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