A neutral conductor carries circuit current in what condition?

The neutral conductor is designed to carry current during normal operation of a circuit. In a balanced three-phase system, for example, the current flowing through each of the three phases is equal and opposite; thus, the neutral wire carries the unbalanced load, which is effectively the difference in current that does not cancel out among the phases. Under normal operating conditions, appliances and devices draw power and return current through the neutral, allowing for safe and efficient operation of the electrical system.

During overloads, faults, or voltage surges, the behavior of the neutral might differ, often leading to higher current than usual or even creating unsafe conditions, but this is not its intended function in standard operation.