ABSTRACT
This chapter explores a three-phase supply that comprises three waveforms each separated by 120 degree and the resultant waveform is zero. It considers how people can utilize the supply and how they can connect to it. The chapter shows that the currents supplied by the generator flow along the lines, through the load and return via the neutral conductor. However, it also shows that all line currents in a balanced three-phase system are equal, and add up to the neutral current, which is zero: Hence the current flowing in the neutral is zero. Also, since no current flows between the star points, they must both be at the same potential, which is also zero. Currents in three-phase systems may be added by the use of phasors. For balanced systems, the resultant current will, of course, be zero and in an unbalanced system the resultant current will be the neutral current.
