电线发热的根本原因是电流通过导体产生电阻损耗，常见诱因包括：负载电流超过线缆额定载流量、线径选择偏小、接头压接不实导致接触电阻增大、散热条件差或环境温度过高等。长期过热会加速绝缘老化，甚至引发短路起火。正确的做法是按负载核算截面并留有余量、规范压接端子、改善通风散热，并定期测温巡检。
1, the conductor resistance of the wire does not meet the requirements, resulting in heat during the operation of the wire.
2, improper selection of wire, resulting in the use of wire conductor cross-section is too small, resulting in overload during operation. After long-term use, the heat and heat dissipation of the wire are unbalanced, resulting in heat.
3, when the wire is installed, the arrangement is too dense, the ventilation and heat dissipation effect is not good, or the wire is too close to other heat sources, which affects the normal heat dissipation of the wire, and may also cause the wire to generate heat during the operation.
4, the joint manufacturing process is not good, the crimping is not tight, resulting in the contact resistance of the joint is too large, and it will also cause the wire to heat.
5, the insulation performance of the interphase wire is not good, resulting in low insulation resistance and heat during operation.
6, part of the sheath of the wire is damaged, and the water will cause slow damage to the insulation performance, resulting in a gradual reduction of the insulation resistance, and also cause heat during the operation of the wire.
