电气线路短路：根据电路公式，如果导线发生短路时，电流可增大为正常时的数

Electrical circuit short-circuit: According to the circuit formula, if the wire is short-circuited, the current can increase to several times or even more than tens of times of normal, and the heat dissipation is proportional to the square of the current. The temperature of the wire rises sharply instantly, and the insulation layer is exhausted. When the temperature exceeds 250 degrees Celsius and reaches the melting point, the circuit will naturally catch fire. In this case, the affected area is also proportional to the length of the short-circuit wire. <br>③Overload: The main reason for line overload is that the cross-section of the wire is not calculated and selected to be too small. When the actual load exceeds the safe carrying capacity of the wire or accidentally connects to too many or overpowered electromechanical equipment, the current exceeds the power distribution The rated load of the line; the wire and cable are affected by the external environment, and the insulation capacity is reduced and damaged. When the current flows in the circuit, part of the current passes between the wires or the wire and the ground, causing the line to overload. <br>④Leakage: due to some reasons (natural or man-made, such as wind and rain, humidity, high temperature, pressure, scratches, friction, corrosion, etc.), the insulation capacity of the aging wire or the support wire The insulation capacity of the cable material is reduced, causing a part of the current to pass between the wire and the wire, between the wire and the earth

Electrical line short circuit: according to the circuit formula, if the wire short circuit, the current can be increased to the normal times or even dozens of times, the heat emitted and the square of the current is proportional, the wire temperature instantly rises sharply, when the insulation temperature exceeds 250 degrees Celsius to reach the melting point, the line will naturally catch fire, in this case, the face and short-circuit wire length is also proportional.<br>(3) overload: the main reason for the line overload is that the wire cross-section is not calculated to choose the small, when the actual load exceeds the safety load flow of the wire or is not intended indirectly into excessive or excessive power of electromechanical equipment, the current exceeds the rated load of the distribution line;<br>(4) Leakage: a part of the leakage of wire path for some reason (natural or man-made reasons, such as wind and rain, humidity, high temperature, pressure, scratching, friction, corrosion, etc.), the insulation capacity of aging wire or bracket wire and cable material insulation decreased, resulting in wire and wire, between the wire and the earth a part of the current through.

Electrical circuit short circuit: according to the circuit formula, if the wire is short circuited, the current can be increased to several times or even tens of times of the normal value, and the heat emitted is directly proportional to the square of the current, and the temperature of the wire will rise sharply. When the temperature of the insulation layer exceeds 250 ℃ and reaches the melting point, the line will naturally catch fire. In this case, the length of the affected surface and the short-circuit wire will also be positive Than.<br>③ Overload: the main reason for line overload is that the conductor cross section is too small without calculation. When the actual load exceeds the safe current carrying capacity of the conductor or unintentionally connects with excessive or excessive power electrical mechanical equipment, the current exceeds the rated load of the distribution line; the insulation capacity of wires and cables is reduced and damaged due to the influence of external environment. When the current is applied in the circuit, part of the power will be supplied The current passes between conductors or between conductors and the earth, resulting in line overload.<br>④ Leakage: due to some reasons (natural or man-made reasons, such as wind and rain, humidity, high temperature, impact, scratch, friction, corrosion, etc.), the insulation capacity of aging wires or the insulation capacity of support wire and cable materials is reduced, resulting in a part of current passing between wires and wires, between wires and the earth