UL Revises Standard for Connect-Ability of LED Christmas Lights
May 12, 2008
UL or Underwriter's Laboratory is an independent product certification organization which creates standards and tests electrical and other products for many U.S. and foreign manufacturers. One of the many products UL certifies is Christmas lights or decorative string lighting. The current certification, known as UL 588, limits the end-to-end connection of string lights to just three sets. This standard has recently been revised to reflect the great differences between LED and incandescent lighting technology.
The old UL standard was really a source of confusion for consumers and vendors of LED Christmas lights, said Philip C. Curtis, President of HolidayLEDs.com. We offered a product that drew between 80-99% less power but UL still only approved the end-to-end connection of 3 light sets, Curtis explained. The UL standard was developed to deal with incandescent Christmas lights and not the more efficient LED improvement.
I spoke to UL about this and I think it was just a matter of them finding the best and safest solution for dealing with the old technology and the new technology, said Curtis. The new UL 588, which will will be mandatory as of March 15, 2010 is available now to any manufacturer who wants to revise its listing immediately. The new standard has a revised paragraph 117.4.2 which allows the each light strings connect-ability to be rated by Watts and Amps. The new standard states:
CAUTION: This lighting string is rated ___ Watts (__Amps), do not overload. Connect other lighting strings or decorative outfits end-to-end up to a maximum of 210 Watts (1.75 amps) total.
Thus, if the light string has been rated at 5 watts, the new standard would allow for the end-to-end connection of up to 42 sets of strings with the same 5 watt rating.
Most manufacturers will have their UL certifications updated within the next year or so. In the meantime it is useful to have UL finally acknowledge that the standard should be different for LED Christmas lights.
For more information about UL approved Christmas lights or HolidayLEDs.com please visit http://www.holidayleds.com