Which material is used for the minimum size grounding electrode conductor required in most commercial installations?

The selection of copper as the material for the minimum size grounding electrode conductor in most commercial installations is based on several important properties. Copper is favored for its excellent electrical conductivity, which minimizes resistance and ensures effective grounding. This is crucial for providing a safe path for fault currents to flow to the ground, thereby protecting both electrical equipment and personnel from electrical shock or fire hazards.

Additionally, copper has high corrosion resistance, which is essential for maintaining the integrity of grounding systems over time, especially in varying environmental conditions. Its durability ensures that the grounding conductor will perform reliably and consistently throughout the life of the installation.

In contrast, while aluminum also has good conductivity, it has lower strength and is more prone to corrosion when exposed to moisture and pollutants. Steel, though strong and durable, does not possess the same level of electrical conductivity and is susceptible to rust, which can adversely affect its performance as a grounding conductor. Plastic, while resistant to corrosion, is an insulator and cannot be used for grounding purposes as it does not conduct electricity.

This combination of conductivity, corrosion resistance, and durability makes copper the preferred choice for grounding electrode conductors in commercial applications.