As we all know, wires and cables have a service life. The designed service life of power copper core wires is between 20 and 30 years, the design life of telephone lines is 8 years, and the design life of network cables is within 10 years. will be bad, but can be used as a reminder.
Factors affecting the service life of wires and cables:
Factors affecting the service life of wires and cables include external force damage, climate environment and overload operation. We must pay special attention to these factors when laying and using wires and cables:
1. External aggression
If the wire and cable are laid in a strong acid and alkali environment, the wire and cable will usually be corroded, and long-term organic chemical corrosion or electrolytic corrosion will age the thickness of the protective layer. Therefore, the influence of this factor should be considered before laying. Adjust the wires and cables and check them regularly.
At the same time, it is necessary to avoid scratches, abrasions and other external factors that damage the protective layer, so as to avoid the degradation of insulation performance and eventually lead to cable failure.
2. Climate and environment
When installing wires and cables, try to avoid exposure to the hot sun or strong wind and rain. Affected by the harsh environment for a long time, it will accelerate the aging of the sheath, thereby reducing the service life of the wire and cable.
3. Overload operation
Do not overload the wire and cable, because the current has a heating effect, and the load current will heat the electrical conductors. In addition, the skin effect of the charge and the eddy current loss of the steel armor and the dielectric loss of the insulation layer also generate additional heat, which in turn increases the temperature of the wire and cable.
During long-term overload operation, excessive temperature will accelerate the aging of the insulating layer, resulting in thermal breakdown of the insulating layer, and even explosion and fire.
Precautions for wires and cables in different laying environments:
1. When laying in underground pipes, generally check the dryness and humidity in the trench regularly.
2. For suspended use/overhead cables, it is necessary to consider the sag and pressure of the cable, and whether the cable is directly irradiated by sunlight.
3. If it is laid in a pipe (plastic or metal), pay attention to whether the plastic pipe is damaged and the thermal conductivity of the metal pipe.
4. It is directly laid in the underground cable trench. Considering the small installation and operation space and complex environment, the installation of the cable trench should check the dryness and humidity regularly.
5. On the outer wall, it is necessary to prevent direct sunlight and artificial damage to the wall.
Post time: Mar-22-2022