For high-voltage lines (typically above 220 kV), conductors are often "bundled," meaning two or more sub-conductors are used per phase. This is done to mitigate a phenomenon called corona effect.

• What is Corona? At very high voltages, the electric field around a single, large conductor can become so intense that it ionizes the surrounding air, leading to a visible glow, a hissing noise, power loss, and radio interference.

• Why Bundle? By using multiple sub-conductors, the effective diameter of the phase is increased, which significantly lowers the electric field gradient at the conductor's surface. This effectively reduces corona losses and improves the overall efficiency of the line. Spacers are used to maintain the correct distance between the sub-conductors.

Ningbo Changshi is a one-stop supplier of the specialized tools and equipment required for the safe and efficient installation of all types of transmission conductors, including the complex setup of bundled conductor lines.