In a three-phase system, if one coil is energized, how is the current distributed among the coils?

In a three-phase system, when one coil is energized, the distribution of current among the coils typically depends on the load balance of the system. If the system is perfectly balanced, the three coils would share the load evenly when energized. However, if there is any imbalance in the system, such as differing loads on each phase or differences in resistance, the current distribution will reflect that imbalance.

In practice, if one coil is energized while the others are not, it will carry the full current as it is connected to the supply. However, if multiple coils are connected with varying loads or if the coils are part of a larger system where the overall load varies, the current shared among the coils would depend on how well the loads are balanced across the phases. This dynamic nature of load distribution in three-phase systems is critical for maintaining system efficiency and stability, making the statement regarding load balance the most applicable answer in this context.