Northbrook, Ill., Oct. 20, 2010: Underwriters Laboratories (UL) is alerting Authorities Having Jurisdiction, facilities managers, contractors, building owners, purchasers and retailers that certain types of tubular fluorescent to LED luminaire retrofit kits when used with luminaires employing shunted bi-pin lampholders could pose a potential fire or shock hazard at the time of installation.
Name of product: Tubular fluorescent to LED luminaire retrofit kits that specify the power is to be connected to only one lampholder as depicted below:
Potential hazard: LED luminaire retrofit kits require the lampholders to be rewired, bypassing the existing ballast. If the LED luminaire retrofit is designed to receive power from only one lampholder, a short-circuit condition in the shunted lampholder will occur and pose a potential fire or shock hazard. Already installed retrofit kits, however, do not pose a potential fire or shock hazard.
Identification: Shunted lamp holders are found only in fluorescent luminaires with Instant-Start ballasts. Instant-start ballasts can be identified by the words “Instant Start” or “I.S.” marked on the ballast. This designation may be in the form of a statement pertaining to the ballast itself, or may be combined with the marking for the lamps with which the ballast is intended to be used, for example F40T12/IS.
What you should do: Do not install tubular fluorescent to LED luminaire retrofit kits in luminaires employing shunted bi-pin lampholders when the retrofit kit instructions specify that line and neutral power be connected to the same lampholder. For more information, contact the LED luminaire retrofit kit manufacturer.