Power factor and three-phaseQuestion 1039 of 1506

When is a Y-connected source the better choice than a delta source?

When no neutral is wanted
When the source must tolerate an open winding
When two voltages (line and phase) are needed
When the line current must be higher

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Correct answer: When two voltages (line and phase) are needed

Y gives both the phase voltage (to neutral) and the line voltage, and can deliver the same power with less line current.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 7.5: Three-phase Y and Delta Configurations

Practice power factor and three-phase

Questions last reviewed: 18 October 2026

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