A 3-phase, 4-wire wye system is supplying a heavily unbalanced lighting load. You measure 15A on Phase A, 10A on Phase B, and 0A on Phase C. Will there be current on the neutral wire?
Answers
AYes, the neutral carries the unbalanced return current
BNo, neutral current in a 3-phase system is always zero
CYes, but only if the system is experiencing a fault
DNo, the current will return entirely on the ground wire
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