What is the primary purpose of bonding in a grounding electrode system and bonding?

• A. To carry current only during normal operation.
• B. To create a low-impedance path to earth, equalize potentials, and prevent dangerous voltages.
• C. To store electrical energy.
• D. To reduce the need for circuit breakers.

Answer: (B)

Bonding and grounding primarily create a safe, low-impedance path for fault currents and keep all exposed metal parts at the same electrical potential. By tying the grounding electrode system to non-current-carrying metal surfaces (enclosures, pipes, structural steel, etc.), any fault—like a live conductor touching a metal part—produces a strong current return path back to the source. Because that path is low impedance, protective devices (breakers or fuses) sense the fault quickly and interrupt the circuit, limiting shock risk and equipment damage.

Equalizing potentials between different conductive surfaces also reduces dangerous touch voltages. If two items at different potentials are touched simultaneously, a person could be shocked; bonding minimizes those voltage differences so a person is less likely to experience a hazardous potential difference.

It’s not about carrying normal-operating current, storing energy, or reducing the need for protective devices. Grounding and bonding are safety measures that enable fast fault clearing and minimize dangerous voltage differences.