Protective measures in electrical installations. Protective measures for indirect contact. Potential equalization. What is potential equalization? Introductory information Potential equalization zone

Modern apartment buildings equipped with various engineering systems and numerous household appliances, metal elements which serve as conductors of electric current and have their own potential. During normal operation, the potential is close to zero and does not differ from the potential of the surface and other surrounding objects. In the event of an accident, for example, insulation damage or potential drift through pipes, the potential of conductive parts can rise to several hundred volts. When a person touches two objects with different potentials at the same time, there is a danger of electric shock. The cause of voltage on metal conductive parts can be not only damaged insulation, but also static electricity, as well as stray currents of grounding systems. If an electric current flows through the grounding device, it also becomes energized and does not guarantee an adequate level of safety.
Reliable protection is provided by the potential equalization system (PSE), organized according to the principle of electrical connection of all conductive parts of the building accessible to touch with a zero protective conductor PE. In this case, potentially dangerous metal elements will have the same potential, which reduces the likelihood of electric shock if they are touched at the same time.

Rationing of the potential equalization system

Additional potential equalization system

In areas of increased risk of electric shock to people, such as a bathroom, sauna, kitchen or shower room, an additional potential equalization system (DSUP) should be installed to ensure a sufficient level of electrical safety in the event of emergency. The additional potential equalization system interconnects all open and third-party conductive parts that are simultaneously accessible to touch, neutral and grounding protective conductors of all equipment (depending on the type of system), including protective conductors of plug sockets. see clause 1.7.83 PUE. The DSUP connection diagram is shown in the figure below.

As can be seen from the diagram, all potentially dangerous conductive structures are connected to the terminal box (bus) in the potential equalization box, which makes it possible to organize a DCS without extending protective conductors from each element to the switchboard of the apartment (house).
The DSUP bus is made of copper with a cross section of at least 10 mm 2, connecting six or more connectors to it.
The PMC is connected to the ground bus of the input switchboard using a copper protective PE conductor with a cross section of 6 mm2, thus grounding all the metal parts of the room. Third-party conductive elements that go outside the premises are also subject to mandatory connection to the DSUP.
In the houses of the new housing stock, the conductors of the EMS are laid at the construction stage, together with the installation of electrical wiring. In case of their absence, for some reason, the conductors can be laid on their own by cutting narrow grooves in the floor screed for this. Before starting work, make sure that there are no other communications in the floor. Conductors are connected to grounded objects by bolting, clamps or welding of contact lugs, which provides a strong metallic bond between them.
DSUP is performed using specially provided conductors or open and third-party conductive elements are used that meet the requirements of clause 1.7.122 of the Electrical Installation Code for protective conductors. see clause 1.7.83 PUE. Provided there is no mechanical impact, the required cross section for conductors is 2.5 mm 2 or more. With a possible mechanical action use conductors with a cross section of 4 mm 2 or more. The connection of two open conductive elements is performed by a conductor with a cross section of at least the cross section of the smaller one connected to them protective conductors. The cross section of the DSUP conductors connecting the open and third-party conductive parts must be at least half the cross section of the protective conductor connected to the open conductive part. see clause 1.7.138 PUE.

Potential equalization restrictions

Installation of the EMS is carried out at the stage of construction of the building. However, there is a limitation on its use in existing buildings. In houses with a TN-C grounding system, with a combined PEN conductor, it is strictly forbidden to perform additional potential equalization. Otherwise, if the neutral wire breaks, there is a danger of electric shock to the rest of the tenants who have not made the DSUP. Typically, this restriction applies multi-storey buildings old housing stock.
The problem is solved if it is possible to switch to the TN-C-S grounding system: for which purpose the PEN conductor is divided into PE and N conductors at the GZSH in the building’s input-distribution device, a ground loop is made and connected to the main ground bus with a copper wire. The current trend to carry out communications (water supply and sewerage) with plastic pipes does not require their integration into a potential equalization system. Replacing metal pipes in the existing DSUP with non-conductive plastic pipes leads to a disruption in the electrical connection with the ground bus of all other metal elements of the room (batteries, heated towel rails, etc.), making them potentially dangerous to humans in case of simultaneous contact.

Conclusion

Modern norms and rules of construction give Special attention correct installation of the potential equalization system. First of all, it is inspected and checked for compliance with the design documentation when the house is put into operation. Electrical safety is ensured by organizing the electrical connection of all conductive parts of the building accessible to touch with the GZSH using PE conductors. OCUP is supplemented by a potential equalization system in areas with an increased risk of electric shock.
It is important to remember that DSUP is only possible in houses with grounding systems with separate laying of PE and N conductors. These include modern system grounding TN-S, as well as an upgraded system to the TN-C-S scheme.
When installing the SIS, it is imperative to ensure a strong metal connection between its elements connected in a radial pattern in compliance with the required cross-section of protective conductors.

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Potential difference, that's what is dangerous for human life. The most dangerous place in our monastery remains the bathroom. To make it a safe place to stay, an additional potential equalization circuit is being laid.

Why extra? The fact is that the structure of the house must have a main ground loop in accordance with all modern building codes and regulations. This means that all metal parts and structures of the entire building are grounded. But in the bathroom they make another, additional potential equalization circuit.

Why is additional potential equalization necessary?

Risers hot and cold water, heating risers, all these parts in the past were made strictly of metal. But as you know, metal has been replaced by plastic - polypropylene pipes. If earlier, when absolutely all pipes were made of metal and a dangerous potential, accidentally appearing on a metal part, could drain into the ground without obstacles, then plastic does not give such an opportunity. For example, you have metal risers, but the neighbor on the floor below changed them to plastic ones. Now the dangerous potential has nowhere to go. Holding on to a pipe on which dangerous potential has accumulated with one hand, and with the other hand on a riser that is grounded, this is just the case that can turn out to be fatal.

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Another danger if there is no additional potential equalization

The bathroom is dangerous for other reasons as well. In addition to metal parts in the bathroom, there is dampness and at the same time many different electrical appliances. Such a dangerous combination just requires measures of increased caution. For this reason, transformations in the form potential equalization. What does it mean?

All metal parts, objects of a stationary nature, are connected with a PE conductor (protective ground) and diverted into one common box KUP (abbreviation KUP - potential equalization box) in the DSUP system (abbreviation DSUP - additional potential equalization system). Then, from the PMC box, the common conductor is brought out to the common terminal PE (protective ground), which is located in switchboard. So we leveled all the potentially dangerous parts, and tried to make the bathroom a safe and quiet haven.

Where it is impossible to do additional equalization of potentials?

It should be remembered that equalization is not done in all apartments. If you have a TN-C grounding scheme for the riser at the entrance, i.e. there is no grounding conductor PE (grounding), equalization is strictly prohibited in the bathroom, even if you have a three-wire wiring in your apartment. Perhaps your apartment is made according to the grounding system, and not according to the grounding system. Potential equalization possible with TN-C-S or TN-S grounding circuits, i.e. a grounding conductor PE (grounding) is laid along the riser of the power line.

Our life is impossible without electricity. And now it is even difficult to imagine how our distant ancestors managed without this necessary and at the same time dangerous energy. Electric wires stretch to each house, ensuring the operation of various household appliances. However, along with them, various equally necessary communications made of metal are laid: pipes, metal hoses, ventilation ducts, etc. The apartments also have a lot metal products. Thus, there is a possibility of electric shock. And to prevent this from happening, such a system as potential equalization is used.

What is it, is it really necessary or can we do without it, we will learn from this article. After all, not everyone is familiar with such a concept, but meanwhile, it is important point on which the life and safety of each of us depends.

Some physics lessons

As we remember from school, and in particular from physics lessons, any conductor has an electrical potential, which in itself is not dangerous. The threat lies precisely in the potential difference between different products, usually made of metal. As this difference increases, so does the risk of electric shock.

To understand exactly what potential equalization is, we can give an example. The metal surface of the refrigerator has its potential, it is safe. A water pipe that may be nearby also has its potential value. And here the main thing is how much the potential of the refrigerator exceeds the potential of the pipe. And as we remember, the potential difference is the voltage. And accidentally touching these objects can pose a serious danger. The human body in this case acts as a jumper on the path from a larger potential to a smaller one. It is worth noting that all pipes and common house communication systems have a close connection with each other.

Someone may object, saying that the magnitude of this voltage is not dangerous for humans, since no phase is supplied to the objects in question. In fact, there are times when even an ordinary ventilation duct can acquire a dangerous electrical potential. And here we smoothly move on to the term potential equalization, which is discussed below.

What does the term SOUP mean?

This definition refers to a special connection of metal structures that conduct current in such a way that no potential difference is created between them. And, as a result, the risk of electric shock is also absent. The potential difference arises against the background of various phenomena:

atmospheric surges;
stray current;
static stress;
circulating ground current.

However, current leakage from the wiring metal structures, which the house is full of, is the most dangerous. Potential can also slip through the cases of household appliances.

In other words, if there is a connection between all products, surfaces or structures, then they all have the same electrical potential. And since there is no potential difference, then there will be no voltage.

Necessary measure

The potential equalization system was not created out of a whim, but is a necessary measure, since we are talking about the life and safety of people. Especially when it comes to providing protection against electric shock in residential buildings. increased attention during electrical work given to all available metallic compounds. The bath and pipelines carry a big risk.

Sometimes different potentials appear on sewer and water pipes. In this case, anyone can get a shock just by touching the faucet. However, this is only possible when these pipes act as a ground electrode or neutral conductor.

The need for such a protective measure is also caused by the fact that most residential buildings contain a considerable number of potential conductors. This is reinforcement embedded in the walls for rigidity. In addition to the water supply and heating systems, usually with metal pipes, there are also air conditioning, ventilation, and lightning protection systems. That is, equalization of potential is rather a necessary measure.

Ground bus

The EMS system alone is not enough, as various unforeseen circumstances may arise. Meanwhile, electricity must be safely diverted at any time. And for this, all conductive objects and elements are united by a ground bus, which is usually installed on the way to the building. And as an additional measure, a conductor coming from the PE electrical panel is connected to the busbar.

What does it give and what will happen if this is neglected? For example, an insulation breakdown occurred in the wiring, and the appearance of a phase on the case is also possible washing machine. Then, standing on the ground, you can get an electric shock, and not only in contact with metal objects, but also with those that do not conduct electricity.

It turns out that a whole electrical circuit is created, through which the current rushes to the ground, but before that it passes through the human body. Thanks to the potential equalization system, all devices and objects are connected to the PE ground bus of the electrical panel, the current energy rushes through the conductor with the least resistance. And a safe current will pass through the human body.

Bathroom - a high-risk area

Bathroom, due to almost permanent advanced level humidity, refers to a dangerous type of premises in terms of electrical safety. In addition, it is here that most of the metal pipes pass. Just in this room or in close proximity to it, a box is placed, and in it is a ground bus. With the help of bolts, conductors are attached to it, which connect all the conductive objects of the room.

It should be borne in mind that only one conductor should go from each metal object or conductive surface. You need to connect all items with a common wire in order to save money. As an exception, you can make a ground loop in a private house, in which there is one serial connection, but without breaking the conductor.

Also, using separate wires, you need to connect all the available sockets in the room. If the bathroom door is metal, which improves the design, it is necessary to ground the door frame with a separate conductor.

In most cases, a box with a tire is installed in the place of the bathroom, where there is an accumulation of pipes. Usually, this area is sewn up by many residents to hide the unsightly view from the eyes. And there is a door for access.

Old is not always safe

In the old days, when the USSR still existed, the grounding system of the TN-C type was widely used. Stalinka, Brezhnevka, Khrushchev - all these houses were equipped with this particular system, which protected residents from accidental electric shock. In it, the protective and working wires are combined into a single conductor, called PEN. He, in turn, connected with switchgear building. The installation of the system was carried out in accordance with the rules for the installation of electrical potential equalization (PUE) of that time.

What was good about her? First of all - the simplicity of work and low cost. The system provides reliable protection against overcurrents. If necessary, circuit breakers are activated. However, there is a significant drawback - this is the absence of a separate ground conductor. This fact calls into question its use in multi-apartment residential buildings.

This type of grounding can be dangerous in the case of single-phase wiring, as it often ignites. But a much greater danger is fraught with a break in the PEN wire, or, as it is also called, zero burnout. This means that a phase may appear on the body of household appliances, which is not good. This usually happens when the current consumption is significantly higher than normal.

Currently, such a ground loop is no longer used in private homes. The same can be said about the construction of new buildings - the TN-C system has already lost its relevance. This is explained by the fact that modern Appliances significantly increased in power. In addition, in the presence of this type of grounding, it is prohibited to install the EMS.

Varieties

There are only two types of soup:

OSUP;
DSUP.

In this case, the first is considered the main one, and the second is an additional measure. They also have differences, but in quality ideal option it's better to use both of them. Let's figure out why.

OSUP system

In modern construction, the OSUP system is provided for at the design stage of buildings, and its installation is carried out before the tenants settle. Part of the system are:

ground loop;
OSUP conductors;
protective PE conductors;
main ground bus.

The main task of this system is to protect the building from the penetration of electricity through any conductive paths. These can be engineering communications pipelines, a metal fire escape and other objects. When a high potential hits them from an external source, thanks to the BPCS, it will be immediately redirected to the ground.

The system successfully works with several types of grounding:

TN-C-S;
TN-S;

During installation, it should be remembered that the connection of conductors of the PE (protective) and N (working zero) types is strictly unacceptable. It is also strictly forbidden to connect when using loops. In addition, switching devices must not be included in the circuit.

DSUP system

If the task of the OSUP system is to ensure the electrical safety of the whole house, then the installation of the DSUP potential equalization system narrows the scope to some specific premises. Often this is the bathroom.

Usually it is not necessary, since the BPCS perfectly provides protective functions. But as soon as the tenants begin to redo something, violating the integrity of the project of the house, then here you simply cannot do without DSUP. Many apartment owners change metal pipelines to plastic ones. Such a forced measure, on the one hand, is justified, but on the other, a problem arises. All electrical connections that were provided by the builders are broken. And this already increases the risk of electrical injury.

In addition to the bathroom, the kitchen can also have high-risk electrical equipment. Consists this system from the following elements:

potential equalization box (kup);
connecting conductors.

According to physical laws, the electric potential tends to change on a long conductor. That is, on the introductory section of the pipe it has the same meaning, and on the 9th or even 15th floor it has a different meaning. And the difference can be significant.

Carrying out the installation of DCS

Before installing the EMS, the first step is to find out which grounding system is used in the building. If TN-C, then it is impossible to carry out work in any case! Such a move could pose a serious threat to neighbors who do not have an EMS.

Before the work itself, you need to make sure that you have:

terminal box (KDUP or KUP) - for a bathroom it is better with protection IP54 or more;
copper single-core wire with a cross section of at least 6 mm;
protective wires;
fasteners (clamps, bolts, etc.).

After that, it is desirable to draw up a diagram on which to indicate the connection of all elements of the circuit, including the path of the conductor from the PMC box to the main ground bus of the electrical panel. And to additional system potential equalization worked well, you need to clean the contact area well under the clamps.

The next step is to install the junction box in comfortable spot. This will be followed by the connection of the PE conductor, which is usually connected to the shield from the external ground loop, with the box bus using the prepared copper wire. After that, it is connected by means of separate wires to each conductive element, according to the drawn up diagram.

Moreover, if there are areas where the conductors of the main potential equalization system will not receive mechanical damage, then a small cross section of 2.5 mm can be used, in other cases it is better to choose a slightly thicker wire (4 or 6 mm).

Final stage

After installation of the DSUP system, it is imperative to take measurements in order to check its performance in order to avoid accidents. To do this, you will need to call an electrician or order the appropriate service from specialists in an electrical laboratory.

When in the bathroom there is electric current from metal pipes, then this problem can be solved by installing special protection for metal objects, which is called a potential equalization system.

Usually in new buildings they plan and implement such protective systems against electric shock. But in old houses, this option does not always work. Let's figure out what the potential equalization system is (its abbreviated abbreviation SUP), its types, and how you can do it yourself.

Purpose

Find out if a potential equalization system is necessary in ordinary apartment. All objects made of metal conduct electricity. We know this from school lessons in physics. In our apartments, dangerous places are heating pipes, as well as water pipes, downpipe, plumbing, heated towel rail in the bathroom, ventilation ducts.

All metal communications in the house are connected to each other. If a potential difference occurs between some metal objects, such as a bathtub and a heating radiator, a person touching these two objects at once can lead to electric shock. This is because the body acts as a jumper between the battery and the bath, so the current flows through the human body from an object that has more potential, to the object with the lowest potential value.

A similar case of danger is the appearance of a potential difference on sewer and water pipes. If there is a leakage of current on the water pipes when a person is washing in the bathroom, there will be a high probability of electric shock when touching the turned on faucet. Water conducts current from the water supply to the sewer, and you complete this circuit with your body.

To eliminate the presence of such a danger, it is necessary to equalize potentials using a special system installed in the apartment.

Kinds

There are two types of potential equalization systems:

Main (OSUP).
Additional (DSUP).

OSUP

This is the main potential equalization system, which is a circuit that combines the following elements of this system:

Grounding.
GZSH - the main ground bus. It is located at the entrance to the building.
Metal parts of the fittings of a residential building.
Ventilation system box.
Metal water pipes (hot and cold water supply).
Lightning protection.

AT early times when all these parts were combined, there was no danger of a potential difference. But today the situation has changed radically, as the owners of many apartments are replacing rotten metal pipes with plastic or polypropylene pipes that do not conduct electricity. plastic pipes break the circuit, resulting in a potential difference between different metal parts in the bathroom.

The main type of system has a significant problem, which is that over a significant length of pipes, for example, in a 12-story building, the electrical potential of the same pipe on the first and last floor will have a large difference. It leads to dangerous situation. Therefore, an auxiliary system is needed, which we will discuss below.

DSUP

This system is optional and is located in the bathroom. It includes the following elements:

Shower enclosure or bathtub.
Towel dryer.
Pipes: gas, water supply, heating.
Sewer system.
Ventilation system box.

Each element of this system is connected by a separate wire to a copper core. The second end of this wire is brought out into a special box (KUP).

There are certain requirements for the creation of a DSUP according to the rules of the PUE:

You can not connect the components of the DCS with a loop.
It is forbidden to carry out DSUP, provided that the ground loop is not installed in the apartment.
The additional system should not be torn along its length from the PMC box to the apartment shield. Switching devices must not be installed in the circuit.

If you don't have this protective circuit, as potential equalization, we will describe below how it can be done on your own.

Installation of a potential equalization system

Installing an auxiliary potential equalization system is not very difficult. It is called the local system. But such work is best done when carrying out repairs in the apartment, since it is necessary to conduct a wire to the shield from the PMC box under the floor, and this is due to a violation of the floor covering, and related repairs.

To start the installation, prepare some materials according to the following list:

Terminal box complete with copper busbar (SHDUP).
Copper wires, consisting of one core. The cross-sectional area of the wires should be from 2.5 to 6 mm 2, brand PV-1.
Fasteners: bolts, clamps, fixing petals. They are required to connect the wires of the entire equalization system to pipes and metal parts.

With this set of elements, you can begin the installation of DSUP. First, a wiring diagram is drawn up in order to perform the correct potential equalization. The diagram also shows the places where the wire passes from the PMC box to the ground bus in the apartment panel. The figure shows one example project.

Further, the communications themselves are preparing for connection, that is, the place of contact of the clamp with the pipe is cleaned, until a metallic sheen appears. This is necessary for the reliability of the connection. In a dangerous situation, potential equalization will work as expected.

Then wires are connected to each element of the system. If you are sure that the wire will not be damaged, then a wire cross section of 2.5 mm 2 is sufficient. But if there is any doubt about this, then it is better to use a 4 mm 2 wire. All conductors are carried into the box and perform reliable connection with tire.

The bathroom terminal box must have a degree of protection of at least IP54. a wire with a cross section of 6 mm 2 should be led from the box bus to the apartment shield. There is a requirement here that this wire should not have intersections with other cables of different lines.

At the end of the work, the wire is connected to the ground bus of the shield. On this installation can be considered complete. For peace of mind, you can call a qualified electrician to check the operation of the system using instruments, as well as visual inspection.

EMS Installation Limitations

It is recommended to install the EMS during the construction of the building. But there are some restrictions on its use in already built houses, in which grounding is carried out according to the TN-C system, with a combined PEN conductor. In such houses it is forbidden to carry out potential equalization. Otherwise, during a break in the neutral wire, there is a risk of electric shock to residents of other apartments in which there is no DSUP. Most often, such a restriction applies to multi-storey buildings of the old fund.

This problem is solved by switching to grounding according to the TN-C-S system. To do this, in the switchboard of the house on the main ground bus, the PEN conductor is disconnected into PE and N wires, the ground loop is connected and connected to the main ground bus with a copper conductor.

Currently, there is a tendency to replace metal pipes with plastic ones, which do not require their connection to the EMS. If you already have additional potential equalization of metal pipes, and you decide to replace the pipes with plastic ones, this will lead to a break in the electrical connection with the ground bus of the remaining elements made of metal. This will make them dangerous to humans when touching several parts at the same time.

New building rules and regulations are aimed at maintaining the correct installation of potential equalization. This system is subjected to inspection, checked according to the project before handing over the house. Electrical safety is created by making electrical connections of all metal parts accessible to human contact with the main ground bus using PE wires.

The main system is complemented by local equalization systems in places with a high risk of electric shock. We must not forget that when installing the EMS, a reliable connection between the elements of the system that are connected in a radial pattern must be ensured. In this case, the wire cross-section must be at least the recommended value.

Potential equalization of lightning protection system

When a lightning strike occurs, a large current strength and its rate of increase occur. Because of this, a potential difference appears greater than from current leakage in the network. Therefore, to create protection against lightning, it is necessary to equalize the potentials.

To ensure that there are no uncontrolled short circuits during a lightning strike, you need to directly connect electrical devices, metal elements, grounding, protective system against lightning with protection devices. The conductors of the entire system are connected to an equalizing bus, which must be accessible for testing purposes, it is connected to an earth loop. Large buildings usually have several of these tires. At the same time, they are all connected to each other.

The lightning protection potential equalization system is carried out at the entrance to the building, and in places where it is impossible to maintain safe distances, for example, at ground level or in the basement.

In a concrete building, either with a metal frame or with lightning protection of a separate design, lightning protection equalization is performed only at ground level. AT tall buildings above 30 meters, lightning protection potentials are equalized for every 20 meters.

Lightning-conducting parts are located at a safe distance from the ECS, in order to avoid impulse flashovers. If such a distance cannot be provided, then auxiliary connections are created between the lightning rod, the lightning rod and the EMS. At the same time, the factor that auxiliary connections make it possible for high potential to enter the building is taken into account.

About the main and additional potential equalization systems and their functional purpose.

Residential building. Lots of floors and apartments. Entire kilometers of communications: wires, metal pipes, ventilation ducts, metal hoses and the like. Our apartments have various metal baths, sinks, and you never know what else. In other words, the whole house is simply full of elements and structures capable of conducting electric current, but often not intended for this.

However, each conductor has electrical potential. It's just a law of physics. Potential is relative. This means that the electric potential, for example, metal surface The fridge itself doesn't matter at all. The only important thing is how much it is higher or lower than the potential of the water pipe passing from it (the refrigerator) in relative proximity.

If there is a difference between the potential of the refrigerator and the potential of the pipe, then this difference can be considered voltage. Someone may assume that such a voltage cannot be significant: after all, both the body of the electrical appliance and the water pipe should not be “under phase”. But you should not rush to conclusions. In fact, there are many reasons why even a harmless metal ventilation duct can acquire a dangerously high relative electric potential.

Among these reasons, for example, are not only the failure of the insulation of the phase conductors of the cables of the power supply system, but also atmospheric overvoltages, stray and circulating currents of grounding systems, and much more.

And what to do? How to protect yourself from all these misfortunes and live in peace, without fear that one day we will be shocked by our own bath?

This issue is resolved by creating potential equalization systems. Its idea is quite simple. If current-carrying parts have a direct electrical connection, then their potential is always the same, and the voltage between them will not arise under any circumstances.

Therefore, the potential equalization system includes everything that can become dangerous: namely, metal pipes, metal structures of the building, lightning protection devices, boxes, trays. All this is connected to main ground bus (GZSH) at the entrance to the building. Such a system is called main potential equalization system.

But for now engineering Communication reach a single apartment located on some high floor, the distance from the GZSH can become impressive. The laws of electrical engineering, characteristic of the so-called "long lines", will come into force.

In accordance with these laws, the resistance of conductors of great length cannot be neglected. That is, the electric potential of the same metal pipe at the entrance to the building and on the fifteenth floor can differ, and very much. Thus, the main potential equalization system becomes less and less effective as you move away from the GZSH.

Therefore, each apartment creates its own, additional potential equalization system. The elements that are included in it are connected to the PE (or PEN) bus in an apartment or house shield. It's over again water pipes, ventilation ducts, and in addition, bathtubs, sinks and other bulky metal objects.

Additional potential equalization system in the bathroom

Not every electrician who undertakes repairs or knows about potential equalization systems and gives them due importance. Therefore, it is better for each homeowner to monitor the condition and quality of the implementation of such a system in his apartment on his own, without relying on anyone else. After all, this is a matter of personal safety.

Alexander Molokov,