What is the primary material used for electrical panel grounding?

The primary material used for electrical panel grounding is copper or aluminum wire. This choice is correct because both copper and aluminum possess excellent conductive properties that are essential for effective grounding. They allow for the safe dissipation of electrical currents and prevent electrical shocks by guiding fault currents safely into the ground.

Copper, in particular, is preferred in many applications due to its higher conductivity and resistance to corrosion, which ensures long-term reliability. Aluminum is also widely used, especially in larger systems, as it is lighter and generally less expensive than copper, while still providing adequate conductivity when properly sized.

The other materials listed do not serve this purpose effectively. Steel wire, although conductive, is not commonly used for grounding due to its susceptibility to rust and corrosion, which can impair its grounding effectiveness over time. Plastic is an insulator, making it unsuitable for grounding as it would not allow for the safe dissipation of electrical currents. Iron, like steel, has similar limitations regarding corrosion and is not typically utilized in grounding applications. Thus, copper and aluminum remain the industry standards for electrical panel grounding.