Safety light i.e. lamp panel, for indicating exit of building, has electronic ballast automatically switching lamp to luminosity level selected for minimal energy consumption and visual inspection, when power supply frequency is not null

摘要

The light (32a) has a controllable electronic ballast (40a) for controlling a lamp (38a) according to a luminosity level and another luminosity level that is higher than the former luminosity level. The former luminosity level is selected for a minimal energy consumption and for a visual inspection of operating condition of the lamp. The ballast automatically switches the lamp to the latter luminosity level when frequency of a power supply of the light is null, and to the former luminosity level when the frequency of the power supply is not null. An independent claim is also included for a safety lighting system comprising a centralized power supply source.