I have always assumed, through school and otherwise, that the neutral of a single phase 120/240v will always carry the unbalance of the two line currents. For instance if line 1 was carrying 5 amps and line 2 was carrying 10 amps the neutral current would be 5 amps. If lines 1 and 2 were both carrying 10 amps the neutral would be carrying 0 amps.
However I had been asked a question that really made me think about this. What if line 1 was carrying a pure capacitive load drawing 5 amps and line 2 had a pure inductive load drawing 5 amps. Would the neutral current still be 0 amps?
What about if line 1 had a pure inductive load drawing 5 amps and line 2 had a pure resistive load drawing 5 amps. Would the neutral current here be 0 amps as well?
Thanks for all information you can provide.
