What is the minimum conductor size for surge protective devices (SPDs) in AWG copper?

The minimum conductor size for surge protective devices (SPDs) is based on ensuring adequate performance in both current-carrying capacity and voltage ratings. According to the National Electrical Code (NEC) and industry standards, a minimum size of 14 AWG copper is specified for the conductors that connect to SPDs. This size helps to mitigate the risk of overheating or damage to the conductor under fault conditions or during surge events, ensuring the safety and effectiveness of the protective device.

By using 14 AWG copper conductors, you achieve a balance between flexibility, ease of installation, and the ability to properly handle potential surge currents without excessive voltage drop. Furthermore, if the conductors were too small, they could potentially fail to adequately conduct the surge current, resulting in diminished performance of the SPD and increasing the risk of damage to connected equipment. Hence, 14 AWG is established as the standard minimum size for these specific applications.