⚡ Why is used 3 phases: can use 2 or 4

This question is often asked by novice handyman before setting out to explore the algorithm works on the wiring in an apartment or private house. However, until recently, it was not a clear answer, and in the course of acquaintance with today's article the reader will understand why. Try to understand why it was used 3-phase, whether there are 2 or 4, a voltage at one or the other type of connection as it is made of electrical switching.

General information about the magnitude of the voltage

If we are talking about wiring in a private home, There is the most commonly used three-phase mains voltage, the value of which is 380 V. However, this parameter is used only for electric motors or other industrial-type equipment. The only exception can be called some hobs the old model. That is why, even if to the input distribution box home suitable 3 phase, they are divided into groups. The fact is that if the division of each of them in a couple of let neutral (zero), then the voltage drop to the usual over the 220 V.

Such systems can be observed in most of the apartment buildings. After all, each of them suitable 3-phase, which is already in the access flaps are distributed from door to door. As a result, each supplied only one phase, zero and grounding. Only in this connection all the usual appliances (fridge, washing and Dishwasher, microwave) Will be able to function normally.

It is possible to connect 2 or 4 phase

Professional electricians who have been educated in the last 10-12 years, say with full confidence that it is impossible. And it would be a mistake. For example, take the welding transformers, manufactured in the Soviet era, which are still relatively new to be found in plants. Their operating voltage is equal to 380 V, but cables for they had only two. And if such a unit is connected according to the logic, then this will be "zero" and "phase". But the snag is that the cook apparatus at such switching will not. They should be connected to 2 phases, without the use of a third and neutral.

The three-phase network has gained popularity

In fact, you can use 4, 5 or even 10 phases, but it would be irrational and raise the cost of the already not cheap electricity. From the viewpoint of reasonableness, the three-phase system of the electromagnetic field is sufficient to rotate the motor. Now imagine that the phase is 5. In this case, increasing the number of motor windings, which leads to unnecessary costs of production, and therefore, increases the final cost of the unit. However, no visible improvements will not be in power.

If we talk about the two phases, for the start of the induction motor will not be enough, it is necessary to install the system, including in the scheme capacitorWhich will provide the necessary shift. At the same drop in power is assured.

A bit of physics: explanation of rational use of the three phases

Speaking figures, it can be noted that the full cycle of rotation of the motor rotor is 360º, and the phase shift in the system voltage of 380 V is 120º. By means of simple calculations it can be concluded that the 3 · 120º = 360. Here is the answer to the question why it was used 3-phase.

To summarize

To date, disputes about how many phases is necessary for greater efficiency is almost subsided. It became clear that the three-phase network are the most comfortable with wiring both in the construction residential homesAnd in the industry. After all, it is for three-wire system is transferred to the high voltage power line, and it also says a lot. So, do not hammer head, thinking about what would happen, whether phase 4, 5 or 6. The extra costs are not wanted.

Editorial HouseChief very much hopes that the issues discussed in today's article, no longer be bothered by our readers. If something remains unclear for you, feel free to ask about it in the comments below. We will definitely explain everything as soon as possible.

If you have a personal opinion on this issue, please explain it as well. HouseChief edition will be very interesting to study it. Finally we offer you a short video, which will help to understand the work of a three-phase system.