The emergency lighting system used in China is mainly of the independent control type with its own power supply. The normal power supply is connected to the ordinary lighting power supply circuit, and it usually corresponds to the charging of the emergency light battery. When the normal power supply is cut off, the backup power supply (battery) automatically powers up. This form of emergency light has a large number of electronic components such as voltage transformation, voltage stabilization, charging, inverter, and battery inside each lamp. The battery of the emergency light needs to be charged and discharged during use, maintenance, and failure. Another type is the centralized power supply and centralized control type, where there is no independent power supply inside the emergency lighting fixtures. When the normal lighting power supply fails, it is powered by the centralized power supply system. In this form of emergency lighting system, all complex electronic circuits inside the lamps are eliminated, and emergency lighting lamps are no different from ordinary lamps. The centralized power supply system is set up in a dedicated room.

In actual construction projects, the selection of emergency lighting power supply should be based on the number of floors, scale, complexity, number of people staying and moving inside the building, production and usage characteristics inside the building, degree of fire danger and importance of the building, as well as the setting of other emergency power sources. Comprehensive consideration and technical and economic analysis should be conducted to select the optimal emergency lighting power supply.