Buying any electrical equipment, whether washer Or a refrigerator, it is not designed for a lifelong service life and in the process of work as any other equipment may break. To protect electrical equipment from abnormal modes of operation (overload or short circuit) various protective devices are used (automata, plugs, etc.)

But there are situations where protective devices do not respond to the damage arising. One of these cases is damage to the internal isolation and the occurrence of high voltage equipment on the metallic housing.

In this case, the protection is necessary for the person himself, which falls under the voltage touched on damaged equipment. To protect against such damage and was invented grounding, the main purpose of which is to reduce the amount of this voltage.

That is, the main estimation of grounding - reduce tension to a safe value.

Suppose you have a ceiling lamp, which is not connected to grounding. In consequence of insulation damage, the metal part of the lamp was substituted. At that moment when you try to change the light bulb you will hit the current, since touching the body you become a conductor and the electric current will flow through your body into the ground.

If the lamp is grounded, most of the current will flush into the ground along the grounding wire and at the time of the touch, the voltage on the housing will be much smaller, and the current value passing through you will also be less.

Mending - The connection of the metal inadvertent parts of the electrical installation with the Earth is called (there is no voltage in normally condition, but may be due to insulation damage.

Also, grounding is necessary for the functionality of such devices as an RCD. If the housings of the electrical installations are not connected to the ground, the leakage current will not flow, which means the RCD, does not respond to a malfunction.

The difference between grounding

Along with the ground, you probably had to hear such a term as a zero.

Rejection - It is called the connection of metal inadvertent parts of the electrical installation with zero (zero network conductor).

In their way destination grounding and zero Perform one and the tight task - protect a person from electric shock. However, they provide this defense a bit different ways. In networks with a reinforcement, it turns off from the electrical equipment, the case of which due to the insulation breakdown was substituted.

Consider an example in which the electrical installation is protected by reassembling.

As can be seen from the pattern when the phase breakdown on the connected to zero, the housing occurs a closed circuit between the phase and zero, that is, a single-phase short circuit. For the resulting short circuit, protective devices react, such as automata or fuses, as a result, it turns off the damaged electrical installation from the power supply.

The above examples make it possible to conclude that:

Surely you had a question in what cases perform ground protection, and in what reassessment. Application in different cases of grounding and reassembly caused by different systems of grounding electrical installations. In electrical installations with voltage up to 1000 V, five ground systems are used: TN-C, TN-S, TN-C-S, TT, IT.

The reinforcement is used as protection in such systems in which Pen, PE or N conductor is present. These are networks with a depth grounded neutral, TN-C, TN-S and TN-C-S.

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Every day in everyday life and at work we have to deal with electricity, which makes human life more comfortable. But, despite the benefits, which gives us the use of electricity. It still represents a certain danger, for example, electric shock. To avoid this, electrical safety requirements have been developed and special protection measures are being taken. Such measures include zealing and grounding. What is the difference between them and whether it is, will understand this article.

All work related to electricity should only be performed by specialists.

The main requirement for household electrical appliances is safety. To greater extent, this concerns devices that are in contact with water, because even a minor defect in the equipment can become fatal for the user. To protect yourself and others, it is necessary to maintain the power grid and equipment in good condition and regularly conduct them revision.To exclude the likelihood of fire due to faulty wiring and electrical damage, it is necessary to install protective devices (RCD).

In accordance with the main rules of electrical safety:

This is just a brief list of electrical safety requirements. In more detail with the rules of security, you can find in various regulatory acts and special literature on electricity, which is now easy to find on the Internet.

What is grounding, principle of operation and device

When creating a power grid, indoors various destinationThe creation of protection that will prevent the likely damage to the current is required. To avoid this, the grounding device is performed. In accordance with PEU § 1.7.53 grounding is performed in electrical equipment with a voltage of more than 50 V alternating and 120 V DC.

Grounding is the intentional connection of the inactive metal parts of electrical installations (which can be energized) with the land or its equivalent. This protective measure is designed to eliminate the likelihood of human damage by electrotock when closed on the equipment body.

Operating principle

The principle of protective grounding is:

• reduce potential difference between grounded element and other conductive items with natural grounding, to a safe value;
• turning current in case of direct contact of grounded equipment with phase wire. In a competently designed power grid, the leakage current causes an instant triggering of the protective shutdown device (UZO).

From the above, it follows that grounding has a greater efficacy when used in a complex with the RCD.

Grounding device

The design of the grounding system consists of a grounding (conductive part that has direct contact with the Earth) and a conductor that provides contact between the grounding and inad -ide elements of electrical equipment. Usually, steel or copper (very rarely) rod is used as a grounding, in industry, as a rule, a complex system consisting of several elements of a special form.

The efficiency of the grounding system is largely determined by the resistance of the protective device, which can be reduced, increasing the useful area of \u200b\u200bearthing or increasing the conductivity of the medium, for which several rods are activated, the level of salts in the ground increases, etc.

Grounding device is ...

We examined above in general featuresWhat is a protective grounding. However, it is worth mentioning that the entrancers used in the system differ on natural and artificial.

As a grounding device, it is primarily preferable to use such natural entries such as:

Important! It is forbidden to be used as an element of grounding pipelines with gas and combustible liquids, as well as heating mains.

Natural entries must be connected to a protective system of two or more different points.

In the role of an artificial earthing machine can be used:

• steel pipe with a wall thickness of 3.5 mm and a diameter of 30 ÷ 50 mm and a length of about 2 ÷ 3 m;
• steel strips and corners with a thickness of 4 mm;
• steel rods up to 10 or more meters long and a diameter of 10 mm.

For aggressive soil, it is necessary to use artificial entrancers with high resistance to corrosion and made of copper, galvanized or coched metal.So, we figured out that it is a definition of the concept of artificial and natural earthing, now we will consider when the ground is applied.

The proposed video clearly explains what a protective grounding is:

When and where the ground is used

As already mentioned, the protective ground is intended to eliminate the likelihood of lesion of people with electric shock in the case of supplying voltage to conductive equipment parts, that is, when closed on the body.The protective ground is equipped with metal inactive elements of electrical installations, which, due to the likely breakdown of the insulation of wires, can be under voltage and harm the health and lives of people and animals in case of direct contact with faulty equipment.

The grounding is subject to electrical stress and equipment with a voltage up to 1000 V, namely:

• alternating current;
• three-phase with an isolated neutral;
• two-phase, isolated from the ground;
• direct current;
• sources of current with an insulated winding point.

Also, the ground is necessary for power grids and electrical installations of direct and alternating current with a voltage over 1000 V with any neutral or middle point of the current source winding.

Main ways of grounding device

When the underlying system is used, vertical metal rods are usually used as a ground. This is due to the fact that the horizontal electrodes due to the shallow depth of the occurrence have increased electrical resistance. Steel pipes, rods, corners and other metal pipes with a length greater than 1 meter and having a relatively small cross section are almost always used as vertical electrodes.

There are two main method of mounting vertical grounding electrodes.

Article on the topic:

Electricity is capable not only to create comfortable conditions Life, but also bears a certain danger. To reduce the likelihood of this danger, required grounding in a private house with your hands 220V . How to do it - read the publication.

Some short electrodes

In this embodiment, several steel corners or rods of a length of 2-3 meters are used, which are connected together with the help of a metal strip and welding. The compound is performed at the surface of the Earth.Mounting the grounding occurs with a simple clogging of the electrode into the ground with a sledgehammer. This method is more famous called "Corner and Sledgeham".

The minimum allowed cross-section of grounding electrodes is shown in PUE, but most often cailed and supplemented values \u200b\u200bfrom the technical circular №11 "Rushelectromontazh". In particular:

The advantages of this method are the simplicity, cheapness and availability of materials and installation.

Single electrode

In this case, an electrode in the form of a steel pipe is used as a ground (as a rule, single), which is placed in a deep hole drilled in the ground. Drilling of soil and installation of the electrode requires the use of special equipment.

The increase in the contact area of \u200b\u200bthe grounding with the soil is provided by a greater depth of installing the electrode. Moreover, this method is more effective in comparison with the previous version, with the same overall length of the electrodes, due to the achievement of deep layers of soil, which usually have low electrical resistance.

The advantages of this method include high efficiency, compactness and seasonal "independence", i.e. Due to the winter freezing of the soil, the electrical resistance of the earthing is practically not changed.

Another way is to lay the entrance to the trench. However, this option requires large physical and material costs (greater amount of material, trench coppe, etc.).

Having understood how it works and for what you need a grounding is now the second question of our article is now, namely, it is a rejection, for which it is necessary and what is different from grounding.

What is a zero

The term reinforcement is denoted by the intentional connection of open networked conducting parts of the power grid and equipment with a deaf-rigged point in single and three-phase networks of direct and alternating current. The reinforcement is performed for electrical safety purposes and is the main protective agent from the stress.

Operating principle

The closure in the power grid occurs when the phase wire located under the voltage is connected with the body of the device connected to zero. The strength of the current increases sharply, and the protective devices that cut off the power from the faulty equipment are triggered. According to the rules, the opening time of the RCD to disable the faulty power grid should not exceed 0.4 seconds. For this, it is necessary that the phase and zero have a minor resistance value.

Article on the topic:

Have you ever heard the abbreviation to learn by reading the review to the end. In short, I would like to add that this device can protect the housing and all its inhabitants from PE, related to electricity.

To create a change in a single-phase network, a third (unused) trin cable wire is used. To create good protection, it is required to provide a high-quality connection of all elements of the system of reassembly.

Device

The system of reassembly, for example, in apartment house, begins with a grounded power transformer, from which neutral with a three-phase line comes to the main distribution shield (rching) of the building. Next happens. From neutral, a working zero is created, which together with the phase wire form a familiar single-phase voltage.

Directly the reinforcement itself to protect the power grid and equipment is created in the shield using a conductor attached to the grounded neutral. You should know that between zero and neutral it is forbidden to install switching devices (automata, packeting, switches, etc.).

Where the scheme is applied

According to the requirements of the PEU, the protective reassessment must be equipped:

• single and three-phase AC networks with grounded output and voltage up to 1,000 V;
• dC power grids having an average ground point and voltage up to 1,000 V.

Grounding cannot save by electric shock, like grounding. This protective circuit simply breaks the voltage supply in the event of a short circuit and turns off the local power grid.

Is it possible to draw a downstream in the apartment by grounding

We already know that such a grounding and reassembly and take out to find out whether it is possible to draw a zero using a grounded zero located in the electrical protection. The fact is that many people are far from electrical engineering are asked by this question and often make unforgivable mistakes, acting in this way.

First, it is prohibited by PEU. The fact is that if, for example, when conducting mounting workFor any reason, to confuse in places in the phase and zero, and besides, it is raised to bring to the working zero, then you can expect the most unpleasant situations. When the electrical equipment is turned on into the network, the housing will be under voltage and the person is affected by the electric stroke, because the defensive operation of the RCD will not occur.

For creating protective reassembly A separate bus connected to a deaf-free neutral is highlighted on the storeflash. And it is best not to fulfill these works on your own, but to instruct a specialist with knowledge in electrical engineering.

The video shows how to create a downstream if it is not on the storey stroke:

What is the difference in grounding

Immediately it is worth saying that despite the fact that grounding and reassembly are protective measures, they have differences on the principle of action and appointment.Grounding is a more efficient and reliable way of protection than the bottomhole, since it allows you to quickly equalize the difference between the potentials to the required value. Also, the grounding has a simpler design and easier to install, and for its device you just need to follow the instructions. In addition, this protective circuit does not depend on the phase of the connected equipment. Emboding options are diverse, and this allows you to choose a specific view for each specific case.

Protective reassembly is a protective measure that, when network faults simply provides an instantaneous termination of the supply of voltage from the power supply through the operation of the RCD. To create a starting and connecting equipment, experience and certain knowledge in electrical engineering are required. All installation work, especially the definition of the bottom of the reasancement, must be performed correctly, otherwise the electrotox is possible in an emergency.

Having understood what grounding and reassembly, many prefer to use both methods. However, the grounding is mandatory when equipped with household and industrial networks, as well as equipment operation.

To better understand what is the difference between grounding and rewarding, we suggest this video:

Earth Requirements and Under

Grounding is a more serious protective measure than reassembling. This scheme requires the creation of a separate tire with a low resistance, which is connected to the entrance to the ground into the ground and equipped in accordance with the standards. All requirements for grounding, its elements and arrangement are registered in PEU and GUT 12.2.007.0.

In the industrial sector, grounding is subject to:

• electric drives;
• electrical equipment;
• metal structures of buildings;
• shielded braid low-voltage electrocabels;
• corps of distribution switchboards and similar structures.

For the downward presented more loyal requirements, namely:

• zero and phase conductors are selected in such a way that when the equipment is trigged on the body, a sufficient current has a sufficient current to trigger a UDO or other protective mechanism;
• explorer from the instrument to grounded neutral should be continuous, that is, do not contain any switching devices in the circuit.

Let's summarize

Ensuring the safety of life and health is the priority of the state, society and naturally the person. To do this, it is necessary to strictly adhere to established rulesinstructions and requirements. One of the factors of human health is electricity, therefore it is very important to ensure sufficient electrical safety in production and in everyday life with the help of certain activities and protective technical means.

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The ground function and reassessment is one - the protection of a person from electric shock. The current-carrying lived, there was a current leakage on the electrical appliance body, the housing was damaged - a single problem was damaged - such a problem could lead to unpleasant consequences. The under considerations under consideration will be avoided, which are designed to neutralize a dangerous factor, ensure the safety of man and its property. In the article, we will tell about grounding and zeroing what the difference and similarity, consider their purpose and installation scheme.

What is the difference between the bottom and ground

The scheme of the reinforcement indicating the splitting on the N and PE on the tibal terminal

It is most convenient to consider the difference between grounding from the connection on the example of connecting household appliances. Modern houses Equipped with a three-wire electrical wiring, where the REE conductor is grounding and does not depend on the conductor of the working zero N. Thus, the electrical appliance body connected to the re-conductor receives a reliable connection with the ground - grounding.

Old buildings have a two-wire power supply consisting of conductor L - phase, N is a working zero. N is output from the grounding tire in a dormitory or driveway electrode. Initially, it is called a PEN conductor and can be split on N and re.

The splitting must be made before entering the apartment distribution panel, or directly in the shield. Next, the wire is connected to the electrical appliance case as in the first embodiment, but such a scheme will be called the reinforcement, since the connection with the Earth is not direct, but is carried out by means of a zero conductor. Read also Article: → ".

What system is more reliable

For comparison, you can familiarize yourself with several points:

• As practice shows, there are no discontinuity cases of cliff or cooling the zero wire in the electrical protection, which makes a non-active protection system. In this case, there is a real threat of human lesion by electric shock. In order to avoid such a problem, the point of switching should be periodically inspecting that it creates certain inconveniences.

The burnt zero wire in the camshaft is close to full cliff

• The grounding system is delivered from these disadvantages, since the re-conductor does not participate in common work wiring and activated only when leakage occurs to take the current to the ground.
• The downgrade device requires certain knowledge and skills of working with electrical chains, which in the case of their absence also causes some inconveniences associated with the need to call an electrician.

Taking into account the above, it can be concluded that the grounding system is more reliable and safe, so it is better to use it. However, in the absence of such an opportunity, you can resort to an alternative option. It is forbidden to change directly in the outlet by installing the jumper between the zero connector and the grounding bracket. This creates a threat to humans (electric shock) and for household appliances.

Device of protective current taps when working with three-phase electrical equipment

The switching of three-phase electricity consumers is different from connecting conventional household electrical engineering, so the device of protective systems is carried out in a different way. At the same time, it is not necessary to confuse the zero or grounding wire involved in the control system, that is, involved in the starting and stopping of the unit, with a protective conductor intended for the diverse discharge on the ground.

Registration, wiring, electrical connection

Works are produced in several stages:

1. The perimeter of the room is equipped with a separate line (highway), made of a narrow metal strip 40x3 mm or copper wire with a cross section of 16 mm.kv.
2. On it in a hidden place is mounted tire (preferably copper) with contact devices (studs or holes for bolted connections). The use of metal tire is allowed, but in this case, the welding of studs is a prerequisite.
3. This line is connected to the grounding circuit or a downstream, derived by a separate wire from the distribution shield and having a reliable connection to the ground or direct, or through a working zero
4. The housings of all consumers (three-phase electric motors) through the copper wire are connected to the tire described.

In the event of a short circuit from the voltage leakage due to the disorders of the insulation or the "breakdown" of one of the phases on the housing of the grounded electrical equipment, the current will immediately go to the ground along the path of the smallest resistance, that is, through the living room connected to the working zero or the ground. This will preserve a person from electric shock when taking the device body. Read also Article: → " ».

The connection device is allowed only in the absence of a switching possibility with an earth contour. In all other cases, only the protective ground is considered correct.

Aggregate through the copper wire is connected to a tire mounted on the grounding route

Mandatory use of additional protective devices

Described grounding and reducing systems are effective in case of significant leaks or short circuits on the electrical appliances housing. However, to achieve full safety when maintaining equipment, it is necessary to use additional funds Protection providing a rupture of the electrical circuit in the event of violations of their operation.

In manufacturing plants, these can be automatic blocks (BKA isolation control or maximum current protection). But the most common means, both in production and in everyday life, are circuit breakers and protective shutdown devices, which:

• will provide de-energization of the electrical circuit in case of malfunctions;
• protect the user from electric shock;
• protect technique from fire.

Such devices may be executed for single-phase or three-phase systems. They are:

• single-pole - installed on one of the lines (zero, phase);
• two-pole - installed on both wires of electrical wiring;
• multi-pole (three or more) are used in three-phase voltage.

Diagram of household wiring with re-conductor of grounding and protecting VA and UZO

The circuit breaker produces shutdown when the current load is exceeded by the nominal value indicated on the instrument housing. The RCO controls the state of the power grid and triggers when the most minor current leaks appear.

Possible malfunctions of the electrical network and the action of protective devices when they occur

The use of users is a description of the most common problems arising from the operation of electrical appliances. For the convenience of consideration of this issue, the information is reduced to the table:

No. p / p	Fault	Protection
1.	Wiring insulation disorder in the wall or ceiling	Grounding (zero) UZO
2.	Current leakage on the case due to moisture, contact disorders, wire overs	- / - / -, Uzo
3.	Short circuit	-/-/-, Automatic switch
4.	The failure of the Tan, the engine (phase breakdown on the body, including through water)	- / - / -, va
5.	Action through the case of the current instrument from the capacitors of the electronics system	- / - / -, Uzo

With a proper protective grounding device (reinforcement) and the use of additional means of protection, these factors will not be able to cause significant harm to the property or human health. Read also Article: → ".

Mounting errors

The most common errors with protection systems are as follows:

In case of absence special Education Or electrical work skills, it is better to entrust the device for protective systems to experienced specialists.

Questions arising from the design of protection systems

Question number 1. Is it possible to make a ground contour under the windows of a multi-storey building and pave the wire into the apartment?

Theoretically, this is possible, but provided that this is the permission of the management company, the grounding resistance does not exceed 4 ohms, as evidenced by the certificate from the standardization department, as well as confirmation from the management of meteorology, that the device does not violate the lightning protection of the building.

You can ground apartment in a high-rise building, but it is difficult to arrange documented

Question number 2. Is it possible to use a water pipeline for temporary grounding until the main one works?

Unambiguously, no one will take to answer this question. It is better for some time not to connect the device at all until the ground is made or reassembled, but as a temporary measure, it is not worth the danger and your neighbors.

Question number 3. Is the metal strip of grounding be powered by a plinth or lay in cable channels?

Can. This will allow you to hide unsightly species and reorganize the interior of the room.

Question number 4. Does the electrician obliged from the serving organization at the request of the tenants to reject in the apartments of old house-building, where there is no grounding?

It is not his direct responsibilities, but if it is necessary to approach the question productive and try to hire it, as a specialist, it is unlikely that someone will refuse additional earnings.

Question number 5. In the accessible panel, the working zero is derived from the terminal bar connected to a common zero, emanating from the general distribution shield. Is it possible to remove the wire with a free terminal?

Sure you may. It will be the very cleavage reported in the article. Moreover, in this case it will be done absolutely true. You just need to make a good contact and pave the wire extremely gently.

In conclusion, we can conclude: create a protective system in any case, under any circumstances. The main thing is that it is competent and reliably arranged and the functions assigned to it effectively fully fully.

Content:

Since the time, electricity was opened, people have fallen many times on themselves his unpleasant and dangerous impact. It was very clear that the practical use of the current is impossible without protective systems. Therefore, all sorts of events were developed, including. They are widely used in industry and power supply schemes for residential buildings. The forms of their application and the main functions are largely coincided, but their use is strictly delimited. In this regard, it is necessary to imagine well what the grounding is different from the reassembly.

Protective grounding

Most often, the safety of electrical appliances and installations is provided by the protective grounding device. The schematic diagram of these devices consists in a forced connection of electrical installations with an earth with significant electrical container. In an emergency, the phase voltage is instantly assigned to the equipment housing.

The ground quality is depending on the resistance value, which should be in the design of the discharge chain. Requirements for the grounding device for each object are accurately defined in PUE.

In most residential buildings, grounding is equipped centrally, which allows, without any concerns, connect any electrical appliances and installations. A more complex and time-consuming protection device can be observed in country houses.

At these objects, earthingers are made of metal profiles or rods. Using a grounding conductor, they are connected to all the devices available in the private house. To reduce resistance in grounding chains, the use of contour metal systems placed at great depth is practiced. The magnitude of the bulk and the design of the contour depends on the materials used and technical characteristics electrical equipment.

Protective zero

The protective reassessment system is one of the types of grounding. In this case, all parts of electrical installations capable of conducting current are connected to zero conductor. The ground itself is directly connected to the neutral of the transformer located on the substation.

When an emergency situation occurs and the phase voltage falls on the body, it leads to the usual short circuit. As a result, the protective devices located in. Therefore, the rise can be safely attributed to the most efficient protective systems.

Differences for grounding

In the grounding systems, the output of excess current and voltage is carried out directly to the ground. To do this, use a special leading system, at the end of which the ground circuit of the triangular configuration is installed. For its manufacture, powerful metal structures connected by welding are used. Grounding should reduce the dangerous level of voltage during contact with electrical installation. The effectiveness of this type of protection affects the quality of execution and constructive features Ground contour.

In many electrical installations a large number of Parts and elements that do not need to be under the character of the action. It is the neutral zero wire that connects. In the case of a touch by these parts of the phase wire, a sharp increase in current occurs. An ordinary short circuit occurs, in which the electrical installation is instantly disconnected from the network. This is the answer to the question, what is the difference between grounding from the reassembly. The zero wire has significantly less resistance than the grounding contour. For this reason, the closure occurs, which is absent from the grounding.

The movement of electricity in homes should be safe and controlled. To prevent negative impact when, due to disruption of the insulation of conductors, critical contact with a person is possible, special measures should be applied: grounding and zero. What is the difference between them? About this in more detail in this review. And the general in these events is that they protect a person from shocking. The directional movement of electrons is carried out along the path of the smallest resistance. You can avoid passing the current through the human body by sending it along the path with the smallest loss. Provides such redirection use in the electrical circuit of grounding or reassembly.

For apartment housing it is easier to draw a zero than to equip the grounding contour.

What is grounding

The essence of grounding lies in the deliberate connection of parts of the electrical installations and the grounding device (as a rule, it is structures made of metal strips and pins that reduce the voltage level to a safe value).

For understanding, consider an example. Suppose in any electrical appliance (washing machine, oven or other appliances) When testing insulation and the voltage between the body of the device and the phase occurs. If there is a grounding device, the current will not lead to critical consequences in contact with the person. This is due to the fact that a protective grounding will perform as a priority conductor having very low resistance.

Resistance to man Various on different sites Body. On average, when calculating electrical safety, it takes equal 1 com.
Ground resistance According to Pue 1.7.62 should not exceed 4 Ohm. Taking into account the resistance of natural earthing and repeated earthing in consumers.

Also, the ground contour is used as lightning protection. In this case, the protective ground takes the high voltage voltage and transmitting it deep into the ground.

By destination, the entrancers are divided into three classes:

• Ground-proof specializes in the discharge of lightning voltage
• The worker maintains the optimal efficiency of electrical installations under any conditions.
• Protective confronts the damage to the living organisms of high breakdown voltage.

The main components of the contour - the earthing and grounding conductors. Grounders can be natural and artificial. In the first case, these are metal structures that have a reliable connection to the Earth. Grounders of artificial origin are made of steel rods, pipes or corners, the length of which should be at least 2.5 m. The connected welds, they are clogged into the ground. By increasing the number of pipes (corners), you can significantly reduce the contour resistance and make it more efficient.

What is a zero

The reinforcement is a connection of open conductive elements of electrical installations that are not in the normal state of a voltage, with a deaf-free output of a source of single-phase electric current (with a deaf-free neutral point of a transformer or generator, in three-phase current power grids; with a grounded source point in DC power grids). This type of protection is often used in apartments where there is no traditional grounding system or it has an outdated look.

The rise in household wiring is performed as follows:

• The substation is connected to the earth of the neutral point of the transformer.
• From the transformer there are three lines connected to homemade electrical protection.
• Next, there is a distribution of apartments.

How does the zero? The peculiarity is that it is designed for the effect of a short circuit, which occurs when the voltage is hosted from one of the phases on the body. After all, the situation may arise when a person touches the body of the device, where there is already a dangerous tension, and the defense has not worked yet. By turning the usual closure to the housing into a short circuit where the phase and zero wire is activated, protective devices are triggered and the automatic shutdown of the damaged electrical installation from the network.

Using this method, be sure. Switch zero conductor, which is used as a protective, prohibited.

What is the difference in grounding?

The difference between grounding from the bottom is, and it is fundamental. If a full ground is mounted, as a result of a phase breakdown on the housing, a rapid decrease in the current voltage to a secure minimum for a person is obtained.

In the case of a change in, due to the breakdown, there is a de-energization of a certain section of the chain, and the short circuit transition to another part or on the electrical appliance body. The risk of a person's fall under dangerous discharge is minimal, but the danger remains.

Video on the topic

Summing up, it can be noted that a more reliable way to protect - grounding. Using the bottomhole is not recommended. But, in any case, it is necessary to approach this issue. In no case do not identify two various methodsThe differences and principle of which were considered in this review. And remember, install the RCD, or the circuit breakers are needed in the complex with both systems.