通常情况下，雷电侵入室内有3个主要途径：一是从电源线入侵；二是从信号线（如通讯线路、电视天线、计算机网络）入侵；三是雷击大地使地电位升高，形成反击。因此，建筑物上的避雷针只能解决建筑物本身的防雷问题，而无法使接通电源的各种电器，尤其是具有信号接收功能的电视 In general, there are three main ways in which lightning intrudes into the room: one is intrusion from the power cord; the other is intrusion from signal lines (such as communication lines, TV antennas, and computer networks); the other is lightning strikes the ground to raise the ground potential and form a counterattack . Therefore, the lightning rod on the building can only solve the lightning protection of the building itself, but can not make all kinds of electrical appliances connected with the power supply, especially the television with signal receiving function