It is reported that when the wires are twisted and wound together, there will be a direct contact resistance. The insulation performance of the protective layer at the connection and the performance of the sealing system are poor, which is easy to cause the wire to oxidize. After the wire is oxidized, it will increase the contact resistance of students. When it is heated, it will expand, and it will shrink when it cools down. The further development will cause the network connection to collapse. In this way, the contact resistance at the connection will become more and more large, forming a vicious circle, and the resistance will increase. It will continue to grow until the heat is disconnected or the insulation layer is burned out, causing a short circuit problem and a fire.
In order to prevent the occurrence of similar accidents, Wuhu Road Sub-district Safety Supervision Station summarizes the lessons of fire accidents, draws on experience, and asks residents and operators in the area at work:
First, the contact of the power cord is poor, and the connection of copper wires (especially hard wires) is difficult to be tight. If high-power electrical appliances are used, it is recommended to use an air switch connection;
Second, the wiring of the wiring board is too thin, the use of high-power electrical appliances will heat up, and even cause a fire in severe cases. It is recommended to replace the wire with a thick point and a large overcurrent;
3. The wiring system in the general room UL power cord should connect as few useless connectors as possible. If one is necessary, it must be connected with an adapter (ceramic material connector) according to the design specification. It is much higher, so that the national safety production electricity can be achieved by reducing the resistance as much as possible.
