In a delta system, how does line current relate to phase current?

In a delta system configuration, the relationship between line current and phase current is defined by the fact that each line current is equal to the square root of 3 (approximately 1.73) times the phase current. This occurs because, in a delta connection, each line is connected to two phases, and the current flowing in the lines is the combination of the phase currents.

When you examine the geometry of the current flow in a delta system using phasor diagrams, the line currents are influenced by the superposition of the phase currents. Since the phase currents are out of phase with each other by 120 degrees, the vector sum leads to the line current being greater than each individual phase current. Specifically, the relationship is expressed mathematically as:

Line Current = √3 × Phase Current

Thus, the correct understanding of this relationship is crucial for applications involving delta connections, as it impacts how load calculations and current ratings are approached for equipment and conductors in these systems.