Which conductor is referred to as the earth or ground wire?

The equipment grounding conductor is specifically designed to provide a pathway for fault current and is used to protect both the electrical system and the people using it by ensuring that the metal parts of appliances or electrical equipment are connected to ground. This connection helps to prevent shock hazards and allows circuit breakers to trip in the event of a fault.

This conductor connects the non-current-carrying metal parts of equipment to the ground, effectively minimizing the risk of electrical shock. When a fault condition occurs, the equipment grounding conductor ensures that the excessive current has a safe path to the earth, facilitating the operation of overcurrent protective devices such as circuit breakers or fuses to de-energize the circuit.

In contrast, the other types of conductors mentioned serve different purposes. The grounded conductor typically refers to the neutral part of a circuit, which carries current during normal operation. The grounding electrode conductor is used to connect the grounding system to electrodes that are in direct contact with the earth. The service conductor is part of the electrical supply that brings electricity to a building. Each of these plays a vital role in the electrical system, but none provide the specific safety function of the equipment grounding conductor.