String cables and connectors fail due to factors like moisture, extreme temperatures, and chemical exposure, leading to corrosion or insulation damage

Wonderful discussion with Shri SK Vali Sir 

 & Shri S. Simhachalam Sir During training.

 String cables and connectors fail due to factors like moisture, extreme temperatures, and chemical exposure, leading to corrosion or insulation damage. Mechanical stress from bending, stretching, or external force also weakens cables. Other causes include electrical overloading, normal aging, and manufacturing defects. The lifespan varies significantly by quality and application, but high-quality, properly installed cables under ideal conditions can last 15-30 years or more, with annual inspection recommended after a certain number of years. 

Causes of Failure

Environmental Factors

Moisture: Infiltration damages cables, leading to corrosion, short circuits, and breakdowns. 

Extreme Temperatures: High heat degrades insulation, potentially causing fires, while freezing temperatures can make insulation brittle. 

Chemicals & UV Light: Exposure can degrade both connector and cable materials over time. 

Mechanical Stress

Bending and Twisting: Repeated or excessive bending and twisting weakens the cable's internal structure. 

Stretching and Pulling: Exceeding the maximum allowable pull force can cause wires to detach or connectors to fail. 

External Damage: Tripping on loose cords or rough handling during transit can cause physical damage. 

Electrical Issues

Overloading: Long-term operation under excessive load can lead to high temperatures and insulation failure. 

Overvoltage: Surges and overvoltages can decrease the cable's withstand voltage, leading to faults. 

High Resistance: In stranded conductors, the initial sign of failure is often individual strands breaking. 

Age and Application

Aging: Over time, cable materials naturally degrade, increasing the risk of electrical accidents. 

Wrong Selection or Application: Using a cable that is not designed for the specific application can lead to premature failure. 

Manufacturing Defects: Design or manufacturing flaws can also be a cause of failure. 

Lifespan

Variability: There is no single lifespan for cables; it depends heavily on the cable's quality, the installation, and the operating conditions. 

Expected Lifespan: Under ideal conditions, a high-quality cable can last for 15-20 years, while some manufacturers and experts estimate the lifespan to be between 20-30 years or more. 

Inspection: Regular inspection is crucial to identify aging and prevent potential electrical hazards and accidents.