What is a typical condition that limits the capacity of a transmission line?

Thermal conditions are a critical factor that limits the capacity of a transmission line because they relate directly to how much current the line can carry without overheating. Every transmission line has a specific temperature rating, which is determined by the materials used and their physical properties. When current flows through the transmission line, it generates heat due to electrical resistance. If the temperature exceeds the line's rated limit, it can deteriorate the conductor's materials, leading to insulation failure, sagging, or even permanent damage.

The capacity of the line is thus limited to ensure safe operation within these thermal limits. Ensuring proper management of thermal conditions helps maintain efficiency and longevity of the transmission infrastructure. Consequently, monitoring and adjusting the power load to avoid excessive heating is essential for reliable and safe operation of transmission lines.