If a copper conductor is used as a grounding electrode conductor, what is the minimum gauge that must be used?

In grounding applications, the National Electrical Code (NEC) specifies that the minimum gauge for a copper grounding electrode conductor is #6 AWG. This requirement is established to ensure safety and reliability in grounding systems. A conductor of this size is able to carry enough fault current to facilitate the operation of overcurrent devices, thereby enhancing the overall safety of the electrical system.

Using a conductor that is too small can lead to inadequate grounding, which may increase the risk of electrical shock or fire hazards. Therefore, employing a #6 gauge copper conductor not only meets the regulatory standards but also provides a sufficient cross-sectional area to conduct fault currents safely.

The other options, which include smaller gauges, do not meet the minimum requirements set forth by the NEC for grounding applications, thus making them unsuitable as grounding electrode conductors.