In a Y-connected circuit, how does the magnitude of each line current compare to the corresponding phase current?

In a Y-connected circuit, how does the magnitude of each line current compare to the corresponding phase current?

• A. It is greater than the phase current
• B. It is less than the phase current
• C. It is equal to the phase current
• D. It is unpredictable and varies

Answer: (C)

In a Y-connected (or star-connected) circuit, the relationship between line currents and phase currents is fundamental to understanding three-phase systems. In such a configuration, each phase is connected to a common neutral point, and the line current flowing in each line is directly the same as the current flowing through the respective phase winding. This occurs because, in a Y-connection, each line is connected to one end of a phase coil, while the other end of the phase coils is tied to the neutral point. As a result, the current that flows in each line conductor is the same as the current that flows through the corresponding phase. This is a crucial aspect of Y-connected circuits that simplifies analysis and circuit calculations. The equality of line and phase currents holds true regardless of the load conditions, provided that the system is balanced. In cases of unbalanced loads, while the individual phase currents may differ, the current flowing in each line remains equal to the respective phase current it is connected to. This consistency is why the correct answer states that the magnitude of each line current is equal to the corresponding phase current. Understanding this relationship is crucial for analyzing and designing three-phase electrical systems effectively.

In a Y-connected (or star-connected) circuit, the relationship between line currents and phase currents is fundamental to understanding three-phase systems. In such a configuration, each phase is connected to a common neutral point, and the line current flowing in each line is directly the same as the current flowing through the respective phase winding.

This occurs because, in a Y-connection, each line is connected to one end of a phase coil, while the other end of the phase coils is tied to the neutral point. As a result, the current that flows in each line conductor is the same as the current that flows through the corresponding phase. This is a crucial aspect of Y-connected circuits that simplifies analysis and circuit calculations.

The equality of line and phase currents holds true regardless of the load conditions, provided that the system is balanced. In cases of unbalanced loads, while the individual phase currents may differ, the current flowing in each line remains equal to the respective phase current it is connected to. This consistency is why the correct answer states that the magnitude of each line current is equal to the corresponding phase current. Understanding this relationship is crucial for analyzing and designing three-phase electrical systems effectively.