What is the minimum size of copper conductors needed for surge arresters on systems over 1000 Volts?

The minimum size of copper conductors required for surge arresters on systems exceeding 1000 Volts is 6 AWG. This specification is established to ensure adequate current-carrying capacity and mechanical strength of the conductors during surge events, which can expose them to significant electrical and thermal stresses.

Using a conductor of this size helps to minimize voltage drop and improve overall system reliability. Additionally, it adheres to safety standards designed to protect both the equipment and personnel working in the vicinity of high-voltage systems. A conductor that is too small may not effectively handle the surge current and could lead to overheating or failure, posing a risk of fire or equipment damage.

While the other sizes may be relevant in certain contexts, they would not meet the required minimum standard for surge arresters in high-voltage applications, which is why 6 AWG is the correct choice.