What are the common faults of overhead cables?

Overhead cables, due to their exposure to external environments, are subject to various influences that can lead to different types of faults. Below are some common types of faults in overhead cables and their causes:

1. Mechanical Damage

• Caused by external forces such as falling trees, vehicle collisions, or construction accidents.
• Prolonged vibrations or swinging can also cause material fatigue in cables.

2. Weather-Related Faults

• Lightning Strikes: Direct hits or nearby lightning strikes can cause overvoltage, damaging cable insulation or even melting conductors.
• Snow and Ice Loads: Accumulated snow or ice increases the weight on cables, potentially leading to breakage or tower collapse.
• Strong Winds: Can cause excessive swaying of cables, which may result in contact between phases, causing short circuits.

3. Aging and Corrosion

• Long-term exposure to ultraviolet light, moisture, and pollutants leads to the aging of insulation materials and corrosion of metal components.
• These factors degrade the overall performance of the cable, increasing the risk of failure.

4. Overloading

• When the current exceeds the design capacity of the cable, it leads to increased temperatures, accelerating insulation aging, and in severe cases, burning out the cable.

5. Animal Activity

• Birds or other small animals may build nests on cables, while rodents might chew through protective layers, creating potential safety hazards.

6. Poor Connections

• Incorrect installation or loosening of connections over time can increase resistance, leading to overheating and potentially causing cable breaks.

7. Environmental Pollution

• Industrial emissions, salt spray, and other chemical substances can erode the surface of cables, weakening their physical strength and electrical performance.

To reduce the occurrence of these faults, regular maintenance checks, timely clearance of environmental obstacles, reasonable design of line routes, and the use of more weather-resistant materials are all crucial measures. Additionally, modern technologies such as online monitoring systems can help provide early warnings of potential issues, allowing preventive actions to be taken.