Power factor and three-phaseQuestion 1062 of 1506

A three-wire Y-Y system (no neutral) has triplen harmonic loads. What happens to the load centre point?

It stays at exactly the same voltage as the source centre point
It carries all of the line current back to the source
It becomes equal to earth potential at all times
It becomes hot, with triplen voltage

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Correct answer: It becomes hot, with triplen voltage

Without a neutral path, the triplen currents cannot flow, so voltages appear instead.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 7.7: Harmonics in Polyphase Power Systems

Questions last reviewed: 18 October 2026

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