UL Warns of Potential Hazard With LED Lamp and Magnetic Ballast Combinations

Ballast

June 4, 2018

Installing double-ended direct replacement LED lamps in energized luminaires powered by magnetic 40 watt ballasts may pose a shock hazard, advises UL.

Recent UL testing confirms that luminaires with magnetic ballasts intended for F40T12 fluorescent lamps may pose a risk of electric shock during installation of LED lamps intended for direct substitution of a fluorescent lamp while the circuit is energized. To date, UL has not received any reports of persons receiving an electric shock while replacing lamps on these older magnetic 40 watt ballasts.

Magnetic ballasts intended for F40T12 fluorescent lamps have not been available in the marketplace for many years. However, given their prior widespread use, these magnetic ballasts may still be in service in some older installations. To enhance safety, UL always recommends that all luminaires be deenergized during lamp installation or replacement.

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