The Universal Emergency Module (UEM) is suitable for class III luminaires with integrated LEDs and separate LED drivers. The UEM will supply the luminaire with up to 3W of power for three hours. The UEM will adjust the DC voltage output within the UEM’s limits to the level required to operate the luminaire and then adjust the current to limit the power to a maximum of 3W to ensure operation time of three hours. The UEM has a replaceable internal lithium-ion battery and can be installed within a luminaire or within the ceiling void to provide a back-up supply in the event of a power cut. The UEM requires a permanent live un-switched supply to maintain the battery charge. In the event of a power cut the battery within the UEM will supply the luminaire through a connection that must be made between the LED driver output and LED luminaire input.