The calculation of the power load of the power grid is the basis for its normal operation. For domestic needs, the voltage of 220 volts is most often used. But this value is not always enough for the normal functioning of all electrical appliances that consume electricity. There are frequent cases when it is necessary to replace the standard voltage with a higher one - 380 volts.
The difference in network structure
The supply of a standard electrical network designed for domestic use consists in laying two cores - with a load and zero. In this case, the voltage between them is 220 volts. This is enough to ensure the normal operation of standard household appliances and lighting elements. But when the load increases, the power cable heats up, which will inevitably lead to either a short circuit or a fire.
In order to avoid such situations in the room, it is necessary to lay not one, but 3 cores. In the vast majority of cases, such an opportunity is provided for in apartment buildings. For the private sector, such a connection can only be made if there is a nearby power line with three separate phases. In addition, it is necessary to draw up permits from the management company and to provide wiring with 4 wires in the room.
When is 380 volt needed?
The need to connect a 3-phase voltage can be caused by several circumstances. In the presence of specific (powerful) equipment or for load balancing in the network.
There is a certain classification of electric networks for which a change in the number of phases is possible:
- Private houses or apartments.
- Production workshops or commercial premises with a branched electrical network.
In practice, achieving at least a temporary increase in voltage to the required level in an apartment or house is very problematic. If you need to connect 380 volts, then good reason is required. For production, most often at the design stage, a 3-phase voltage is provided. This is due to the high power of the equipment and the constant load on the network.
Private houses and apartments
When designing apartment buildings, the calculation of energy consumption is performed. Based on these data, wiring of the corresponding section and safety devices is established. If, for some reason, an increase in power consumption occurs , it is recommended to connect 380 volts.
This may be due to the following factors:
- The installation of powerful household equipment - a heating boiler, climate control system, etc.
- Conducting temporary repair work, during which electricity consumption will increase significantly and the load on the network will increase.
Depending on this, a permit is issued for temporary or permanent changes in the network parameters at which the voltage of 380 volts will become the main one.
The procedure for obtaining permission
There are certain rules for changing current parameters in the mains. To obtain permission at the first stage, design documentation is prepared . It indicates the types of equipment and their characteristics. Based on these data, the management company should give a technical condition for a voltage of 380 volts. How to connect and which power lines should be involved for this, the engineer decides.
After that, an act is drawn up, which indicates the following points:
- The necessary package of documents for the ownership of an apartment (house).
- The technical project mentioned above.
- The report, compiled on the basis of the company representatives checking the equipment parameters and the documentation attached to it.
If the requirements are justified - a significant increase in power consumption in accordance with the standards in the equipment certificates, then a voltage of 380 volts is connected and connected.
For private homes, the procedure is slightly different. If there is a 3-phase line at a distance of at least 500 m from the building, then all work on connecting it (after approval of the permit documentation) is carried out by the management company. Otherwise, an increase in voltage in the house is impossible.
Commercial and industrial use
For buildings and structures with constant heavy loads, the voltage of 380 volts is set by default. This applies directly to all industrial and commercial facilities. To ensure normal electricity supply, the schemes provide mechanisms for monitoring and distributing voltage depending on the load in a particular area. Compilation of such design documentation is carried out by specialized companies, which are certified without fail.
Is it worth it to draw a 3-phase line to a private house or apartment in advance? This is possible only if the design rules are observed, which must indicate the types of electrical equipment and their characteristics.