What is the primary purpose of main bonding in an electrical installation?

What is the primary purpose of main bonding in an electrical installation?

• A. To connect extraneous conductive parts to the earthing system
• B. To connect the neutral to earth
• C. To connect live to earth
• D. To connect shielding to earth

Answer: (A)

Bonding extraneous conductive parts to the earth ensures all metal parts that could become energized are kept at earth potential. This minimizes dangerous voltage differences between metal surfaces that you might touch, and it provides a low-impedance path for fault current so the protective device trips quickly. By tying things like metal water or gas pipes, metal enclosures, and other metallic services to the earth, a fault won’t leave one part at a high potential while another remains at a different potential. It’s not about neutral-to-earth or live-to-earth connections in normal operation, and bonding these parts is not about shielding.

Bonding extraneous conductive parts to the earth ensures all metal parts that could become energized are kept at earth potential. This minimizes dangerous voltage differences between metal surfaces that you might touch, and it provides a low-impedance path for fault current so the protective device trips quickly. By tying things like metal water or gas pipes, metal enclosures, and other metallic services to the earth, a fault won’t leave one part at a high potential while another remains at a different potential. It’s not about neutral-to-earth or live-to-earth connections in normal operation, and bonding these parts is not about shielding.