The phenomenon that the wire connector generates heat generally first manifests itself as an odor around the wire connector, which can be heard because of the heat generated by the wire connector causing it to produce an odor in the outer insulating layer; secondly, smoke, redness, and blackening of the outer insulation layer at the wire connector. , fire, and even broken lines. Not only will the heating of the wire connector cause a great deal of power loss, but it will also seriously affect the normal operation of the electrical equipment. If the operating current is increased in the circuit, the life of the electrical equipment will be shortened, and the ongoing production, scientific research, and medical care will suddenly be interrupted. Surgery and other activities can also result in fires, electric shocks, etc., causing incalculable damage.

Some electrical installation workers often pay attention to the installation quality when laying wires: no bushing should be used at the place where insulation bushings should be used; no junction box should be installed where the junction box should be used; even at the wire joints, the splice method is not used. Instead, it uses illegal hook-like connection methods. Such a hook-shaped connection method has a large contact resistance, and generates heat continuously when it is energized, which causes the nearby wood board to gradually dry, charring, and eventually burning to cause a fire.