The lightning protection module of AC power supply is suitable for power protection of power distribution room, power distribution cabinet, switch cabinet, AC /DC power distribution panel, communication, electronics, electric power, network, energy, railway, highway and other systems; There are outdoor input distribution boxes and building floor distribution boxes in the building; Used in low-voltage (220/380VAC) industrial power grid and civil power grid; Signal arrester is used for overvoltage protection of line intrusion; Lightning rod is used for direct lightning protection; In power system, it is mainly used as the input or output end of three-phase power supply in the power panel of automation machine room and substation master control room.