The Reason Why the Cable is Hot During Operation

When the power cable passes a certain load current, it always exceeds or exceeds the maximum continuous working temperature allowed by the cable (the maximum allowable temperature of the XLPE insulated cable is 90 °C), and the cable will heat for a long time. If the cause is not found, the cable is removed in time. After continuous continuous power-on operation, insulation thermal breakdown will occur, causing phase-to-phase short-circuit tripping of the cable, which may cause a fire. The heating of the cable during operation may be caused by the following reasons:

1. The DC resistance of the cable conductor does not meet the requirements, causing the cable to generate heat during operation.

2. The cable selection type is improper, causing the conductor cross section of the cable to be used to be too small, and an overload phenomenon occurs during operation. After a long time of use, the heat generation and heat dissipation of the cable are unbalanced to cause heat generation.

3. When the cable is installed, the arrangement is too dense, the ventilation and heat dissipation effect is not good, or the cable is too close to other heat sources, which affects the normal heat dissipation of the cable, and may also cause the cable to generate heat during operation.

4. The joint manufacturing technology is not good, the crimping is not tight, and the contact resistance at the joint is too large, which may cause the cable to generate heat.

5, the cable phase insulation performance is not good, resulting in less insulation resistance, heat generation during operation

6. The partial sheath of the armored cable is damaged. After the water enters, the insulation performance will be slowly destructive, resulting in a gradual decrease in the insulation resistance, which will also cause heating in the cable operation.