Engineering Board Exam Reviewer · Three-Phase Systems in Power Applications · easy
In a balanced three-phase, four-wire wye system the current in the neutral conductor is
- equal to the line current
- 3 times the line current
- zero
- three times the line current
Answer
C. zero
Solution
The three line currents have equal magnitudes and are 120° apart, so their phasor sum is zero. Therefore the neutral carries no current when the load is balanced.
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