Power factor and three-phaseQuestion 1038 of 1506

Why is a delta source preferred when reliability is the main need?

It has a neutral wire for single-phase loads
It keeps supplying the load if one winding fails open
It has lower line current than a Y source
It gives two load voltages from one source

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Correct answer: It keeps supplying the load if one winding fails open

The other two windings still hold the full line voltages.

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

Questions last reviewed: 18 October 2026

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