What causes power cables to heat up?

What causes power cables to heat up? Follow the flexible cable manufacturer Xiaobian together to have a look!

When the power cable passes a certain load current, it is always higher or exceeds the higher continuous working temperature allowed by the cable (the higher allowable temperature of the crosslinked polyethylene insulated cable is 90℃), and the cable will get hot for a long time. If the cause is not found and the fault is removed in time, the thermal breakdown of insulation will occur after the continuous power operation of the cable, resulting in the occurrence of interphase short circuit trip of the cable. Serious may cause fire. Cable heating in operation may be caused by the following reasons:

1. The DC resistance of the cable conductor does not meet the requirements, resulting in heating in the operation of the cable.

2. Cable selection is improper, resulting in

When the power cable passes a certain load current, it is always higher or exceeds the higher continuous working temperature allowed by the cable (the higher allowable temperature of the crosslinked polyethylene insulated cable is 90℃), and the cable will get hot for a long time. If the cause is not found and the fault is removed in time, the thermal breakdown of insulation will occur after the continuous power operation of the cable, resulting in the occurrence of interphase short circuit trip of the cable. Serious may cause fire.

Cable heating in operation may be caused by the following reasons:

1. The DC resistance of the cable conductor does not meet the requirements, resulting in heating in the operation of the cable.

2. Improper cable selection, resulting in the use of cable conductor section is too small, overload phenomenon in operation, after a long time of use, cable heating and heat dissipation imbalance caused by heating phenomenon.

3. The arrangement of cable installation 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 in operation.

4. The joint manufacturing technology is not good, and the crimping is not tight, which causes the contact resistance of the joint to be too large, and also causes the cable to generate heat.

5, cable phase insulation performance is not good, resulting in small insulation resistance, will also produce heating phenomenon in operation

6, armored cable local sheath damage, water caused by slow damage to the insulation performance, resulting in gradual reduction of insulation resistance, will also cause heat in the operation of the cable.

In order to ensure the safe operation of the cable, the following factors should be considered in the selection of power cable design:

1. The rated voltage of the cable must be greater than or equal to the rated voltage of the power supply system at the installation point.

2. The continuous allowable current of the cable should be equal to or greater than the larger continuous current of the power supply load.

3, the core section to meet the stability of the power supply system short circuit requirements.

4. Check whether the voltage drop meets the requirements according to the cable length.

5, the small short circuit current at the end of the line should be able to make the protection device reliable action.

6. High breakdown strength.

7, low dielectric loss.

8. Very high insulation resistance.

9, excellent discharge resistance.

10. It has certain softness and mechanical strength.

11. Long-term stability of insulation performance.

The conductor section of the cable used is too small, resulting in overload phenomenon in operation. After a long time of use, the imbalance between heat and heat dissipation of the cable causes heating phenomenon.

3. The arrangement of cable installation 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 in operation.

4. The joint manufacturing technology is not good, and the crimping is not tight, which causes the contact resistance of the joint to be too large, and also causes the cable to generate heat.

5, cable phase insulation performance is not good, resulting in small insulation resistance, will also produce heating phenomenon in operation

6, armored cable local sheath damage, water caused by slow damage to the insulation performance, resulting in gradual reduction of insulation resistance, will also cause heat in the operation of the cable.