We are constantly confronted in our home, in the office and production facilities with electrical appliances, which are conductors of electric current. These can be central heating batteries, gas stoves, baths, pipes, etc.. P. Such conductors have an electric potential of various magnitudes with a fairly high value.
About potential differences
If the magnitude of the potentials of conductive objects in the room is different, then there is tension between them (potential difference), which poses a great danger of electric shock to humans. It is especially important to take this into account when connecting devices in rooms with high humidity (sanitary rooms, showers).
The difference in electrical potentials in household appliances and pipes in the apartment may result:
- leakage current due to damage to the insulation of the wires;
- incorrect connection of electrical equipment;
- faulty electrical appliances;
- manifestation of static electricity;
- occurrence of stray currents of the grounding system.
To prevent situations of potential differences in the room, the system of equalization of potentials is carried out (SOUP) - parallel connection of all metal structures, which are in the house. The basis of the SUP is the integration of conductive objects into a single circuit.
The building provides for the installation of both the main grounding circuit and additional equipotential bonding systems in accordance with the requirements of modern rules and regulations. The main system includes metal structures of the building: fittings, ventilation boxes, pipes, details and elements of elevators and lightning protection.
Engineering communications have a considerable length, which increases the resistance of the conductors. In this case, the electrical potential of metal pipes on the top floors of a high-rise building is much greater, than in the pipeline on the ground floors.
in addition, Recently, metal pipes are beginning to be replaced by plastic ones. Thus batteries and towel rails, which are made of metal, deprived of protection, as the plastic is not a conductor and has no connection to the ground bus. Therefore, an additional equipotential bonding system is installed to solve such problems (DSUP).
Equipotential bonding boxes
Equipotential bonding box (KSP) Is one of the elements of the system of protection of people from the danger of electric shock. The device is used in the organization of DSUP in the room (office, apartment, home, etc.. d.).
There are different types of PMC depending on the construction of the building:
- in a hollow wall;
- in solid walls;
- open installation.
Types of installation
Installation of PMC for metal pipes
PMC is a plastic case, where the inner bus is located is the most important part of the earthing device. It connects the conductors to the metal pipes of the hot and cold water supply, gas supply, sewerage, heating, as well as electrical appliances, indoors. Ground wires from sockets and switches are connected to the box. The conductor is taken from the inner bus to the apartment shield, through which there is a connection to the main ground bus, located at the entrance to the building.
Installation of PMC for plastic pipes
At installation of plastic pipes in SUP metal cranes and mixers join. Metal-plastic pipes can also have dielectric inserts, which connect to the main office.
The system provides the same potential of all metal elements in the building. In case of voltage on any object, it will move through the ground wire to the common circuit.
The junction box is installed as follows, so that it does not disturb the interior of the room. When installing systems, you must follow certain rules:
- installation of PMC is carried out in the place of passage of risers;
- free access to the PMC is provided;
- obligatory connection of all available open elements of electrical equipment, as well as protective conductors and third-party conductors;
- installation of the system in the bathrooms, bathrooms are mandatory.
SUP is created during the construction of the house. If it is absent in old buildings, then for the purpose of electrical safety installation of such equipment is carried out. In order to efficiently and safely install the PMC, the grounding system of the building is being studied.
In some cases, the installation of PMC is prohibited. So, if the grounding circuit is installed in the entrance without a grounding conductor, then equalization of potentials cannot be done. Therefore, such work should be entrusted only to specialists.