Grounding conductors are required by the National Electrical code in the United States and by most other major electrical codes in the world. Grounding conductors connect all of the non-current carrying parts of the electrical system, or any metallic parts in the vicinity of the electrical system together. This part includes conduits, enclosures, supports and other metallic objects. This grounding system has two purposes:

Safety. The grounding conductor system provides a low impedance path for fault currents to flow. This allows the full current to be detected by over current protective devices (fuses and circuit breakers), safely clearing the fault quickly.

Power quality. The grounding system allows all equipment to have the same reference voltage. This helps the facility electronic equipments operation and helps prevent the flowing of objectionable currents on communication lines, seals and other connections.