The VEM500DV-L, LED emergency ballast works in conjunction with the AC ballast to allow the same fluorescent fixture to be used for both normal and emergency operations. When AC power fails, the VEM500DV-L switches to emergency mode and keeps the lamp(s) illuminated at a reduced lumen output for a minimum of 90 minutes. The VEM500DV-L is suitable for use in new fixtures or retrofit applications. Includes LED charging indicator light, single-pole test switch, and installation hardware.