What connects the equipment grounding conductors to the grounded (neutral) conductors?

The main bonding jumper is the component responsible for connecting the equipment grounding conductors to the grounded (neutral) conductors at the service entrance of an electrical system. This connection is critical because it establishes a low-resistance path for fault currents to flow back to the source, ensuring that overcurrent protective devices function correctly in the event of a fault. By bonding the grounding and grounded conductors, the risk of potential differences that could lead to shock hazards is minimized.

In contrast, the grounding electrode refers to the physical connection to the earth, which provides a pathway for lightning strikes or surges, but it does not directly connect grounding conductors to neutrals. The equipment bonding jumper is used to connect non-current-carrying conductive parts of equipment to the grounding system, but it does not specifically address the connection between grounding and grounded conductors. Lastly, the grounded conductor, or neutral, is the conductor that carries current under normal conditions; it is not a physical connection mechanism but rather a pathway for return current. Therefore, the main bonding jumper is essential for creating the necessary link that enhances safety and system reliability by properly interconnecting these conductors.