In a balanced 3-wire, 120/240V circuit, what percentage of the ungrounded conductor current is the current on the grounded conductor?

In a balanced 3-wire, 120/240V circuit, the system is designed so that the current flowing through the ungrounded conductors (the hot wires) is balanced and equal at any given moment. In this setup, the grounded conductor, often referred to as the neutral, carries the difference of the currents of the ungrounded conductors.

Since the circuit is balanced, when the loads are even across both hot wires, the currents in the ungrounded conductors effectively cancel each other out. This means that the current flowing through the grounded conductor (neutral) will be zero in an ideal balanced scenario. Therefore, the percentage of ungrounded conductor current that is found on the grounded conductor would be 0%.

This principle is critical for ensuring that the electrical system operates safely and efficiently, preventing overloading of the neutral and enhancing the safety of the electrical installation.