Which conductor's continuity is critical in a multiwire branch circuit?

In a multiwire branch circuit, the continuity of the grounded conductor, commonly known as the neutral, is critical because it serves a vital role in the safe and effective operation of the circuit. The grounded conductor provides a return path for current in a circuit that typically combines multiple hot conductors sharing a common neutral. If the grounded conductor is interrupted or has a poor connection, this can create an imbalance in the circuit, leading to potential safety hazards, including overloading or elevating voltage on the other conductors.

The grounded conductor is also essential for ensuring proper operation of circuit protection systems. If an issue arises, such as a fault or overload, the grounded conductor can help direct fault current to protective devices like circuit breakers or fuses, thereby preventing electrical fires or equipment damage. Therefore, maintaining continuity of the grounded conductor is paramount for both safety and functionality in a multiwire branch circuit.