For a wye connected device, how does the line current compare to the phase current?

For a wye-connected device, the line current is equal to the phase current. This relationship arises from the configuration of the connections in a three-phase system. In a wye (Y) configuration, each phase is connected to a common neutral point, and the line current flows directly to each of the phases. Because each phase has its own distinct connection to the line, the current that flows through the line to each phase is exactly the same as the current flowing through that phase.

This leads to the understanding that in a wye-connected system, there is no transformation or multiplication of current as seen in delta connections. In contrast, in a delta connection, the line current is actually greater than the phase current due to the way phases are interconnected, specifically the use of the square root of three factor. Recognizing the difference in configurations helps in analyzing and understanding the behavior of electrical systems in various setups.