The three live wires of a three-phase generator can of course be combined with each other if they are isolated from each other, otherwise they will be short-circuited.
In actual use, the three-phase conductors must also pass through a metal wall bushing. Only in this way can the metal bushing be prevented from heating up. Some electricians worry that there will be problems if the three-phase conductors pass through steel pipe together, so they use one steel pipe for each phase. As a result, the steel pipe will burn red.
There is an electromagnetic field around the live wire, which will form electromagnetic induction on the surrounding ferromagnetic objects, forming eddy currents in the surrounding ferromagnetic objects. On the one hand, eddy currents will generate heat (when). the current is very important, these induction eddy currents can makee burn the steel bars in the concrete walls) and on the other hand increase the losses of electrical energy.
The electromagnetic fields around three-phase live conductors have time and phase differences, but there is a rule: the vector sum of the three-phase currents is zero, so the electromagnetic fields around the three conductors under voltage in phase cancel each other out and are almost equal to zero.
Therefore, it is better to group the three-phase conductors together rather than arranging them in a scattered manner. Common three-phase cables have three conductors together. That's the reason.
No, simply connecting a live wire will not loop and the electrical equipment will not operate. If two live wires are connected and 220 V electrical equipment is connected to a voltage of 380 V, the equipment will be burned. From a certain point (generally at the level ofmain switch or input line), connect the three neutral wires together and route one wire to each of the three users.