How is equipment grounding typically accomplished in 120-volt house wiring using non-metallic sheathed cable?

In 120-volt house wiring that employs non-metallic sheathed cable, grounding is crucial for safety, preventing electric shock and ensuring that circuit faults are safely managed. The correct method for grounding in this scenario involves connecting the bare grounding wire to the ground bar, which is typically found in the service entrance panel or breaker box.

In this setup, the ground bar provides a common connection point for all the ground wires throughout the electrical system. This connection helps ensure that any fault current caused by a short circuit or equipment malfunction is directed safely to the ground, reducing the risk of electrical hazards.

The connection to the SEP (Service Entrance Panel) neutral bar specifically is important because, in residential systems, the grounding and neutral are typically bonded at the main service panel. However, grounding should not be exclusively tied to the neutral as it could create a potential hazard; the grounding system is designed to function independently to provide a safe path for fault currents.

Other methods such as using insulated wire or attaching to the device's ground terminal do not provide the systemic safety benefits that come from tying the grounding wire to the ground bar. A well-designed grounding system is integral to ensuring reliability and safety in electrical installations within residential settings.