Wire, you can run. Why don't you take the center line?
Ramming machine regardless of star delta connection, only three FireWire, you can run. There is no need to use the center line. The phrase "Three - phase transformer has middle line" is a noun.
In addition to the power system 380/220 power supply system with zero line (the one hand to meet the power and single-phase electricity, on the other hand, the user is not easy to do three single-phase distribution balance, so the zero line voltage), the other is basically balanced, does not need the zero line.
The three phases of an electric motor are balanced. Neither the star nor the horn requires zero lines, as long as the three lines are on fire.