Correct connection of the cable to the circuit breaker. Connecting a circuit breaker - how to do it yourself

Sometimes even the simplest manipulations and connection of simple electrical devices such as a light switch or an automatic device can cause a lot of questions. In principle, nothing is difficult, you just need to clearly understand:

1. the purpose of each element of the circuit;
2. safe techniques for connecting the switch;
3. nominal values \u200b\u200bof each apparatus;
4. know the power supply system and the geography of the location of electrical devices.

The list of tools that will be needed for this is also minimal:

1. Indicator screwdriver or voltage indicator with phase indicator;
2. A screwdriver with a strong handle made of good steel, which will ensure a reliable clamping of the bolted contact connection;
3. Pliers;
4. Insulating material (electrical tape).

Of course, all these rules and techniques are applied to connect and install household circuit breakers, as well as lighting switches. In industrial premises and conditions, connecting an automatic power switch is a time-consuming work associated with large-sized electrical devices, and there will already be need for socket and spanner keys in order to reliably and efficiently mount the housing and the contact part. In everyday life, a phase voltage of 220 Volts is most often used, which is a consequence of being connected to a three-phase circuit with a dead-grounded neutral. That is, in order to get this voltage equal to 220 Volts, you need to connect to the phase conductive cable and to the neutral wire. Between the two phases, the voltage will already be 380 volts. This voltage is used in everyday life, most often in their own houses and cottages, when you need to connect a three-phase motor (compressor, fan, pump) without power loss.

Connecting a double pole circuit breaker

Before connecting a circuit breaker, you need to understand the purpose of this device, its functions and capabilities. An automatic two-pole switch is, by and large, two single-pole circuit breakers assembled in a single case. According to the PUE, it is impossible to disconnect only one phase wire or zero, to ensure the safe operation of electrical installations.

This device has several protections:

• From a short circuit, that is, from a sharp increase in large currents that arise in this case in the circuit;
• From a prolonged increase in current more than the nominal, by a predetermined and clearly advertised value.

That is, the machine will turn off abnormally if, for example, it is designed for a working current of 20 A, and within 20 minutes, for example, 25 A will flow through it, a thermal relay will work in it, which can prevent it from being turned on again. Only after the circuit breaker, or rather, its thermal relay, cools down to operating temperature, will it be possible to re-enable. And also the machine turns off if a short circuit occurs in the outgoing circuit, that is, the one that went to the consumers.

How to connect correctly

To connect the switch, you first need to decide on the energy source, that is, where it will be powered from. The installation of circuit breakers in the panel will be carried out in any case, too, from a machine with only a higher rating.

But selectivity must be maintained. Selectivity is a well-tuned and matched mechanism for protecting devices in electrical circuits, as a result of which the circuit breaker is disconnected in this section of the circuit and it will be the closest to the place of short circuit or overload. In other words, if the power supply system of an apartment or room is divided into several parts, then in the event of a short circuit in the circuits in the kitchen, only the automatic supplying this kitchen will turn off, and not the input to the entire apartment.

A source is known to which you can connect the upper contacts of the machine, now you need to decide whether it will withstand all the loads and all consumers that will be connected. Each electrical device has its own ratings:

1. Power consumption;
2. Voltage;
3. Current strength.

Each of them is important, but sometimes only power and voltage may be indicated on some devices. The approximate current strength can be determined by yourself; for this, the power of the electrical appliance must be divided by its operating voltage. The power supply should be selected in accordance with the sum of all devices that will be connected to it. For example, if there are three electrical devices that will consume 5 A each in the course of their operation, then the circuit breaker should be slightly with a margin of 20-25 A. Then the flowing operating current will be 15 Amperes, with the operating current of the machine 25. Everything the devices will work normally without overheating. And in emergency modes, they will immediately turn off the entire circuit, thereby ensuring reliable fire safety of the room. The polarity in AC voltage circuits does not matter, so there is no difference to which terminals the phase will be connected, and to which zero. In DC circuits, double-pole switches are also often used. One of the conclusions is negative, the other is positive, however, constant voltage is used very rarely in domestic conditions.

Connecting a single pole circuit breaker

A single-pole switch is designed to switch lighting circuits, or even sockets. The main advantage of bipolar is lower cost. The main thing in creating and supplying circuits connected through such a device is that it must necessarily break the phase wire, the zero one can be connected directly to the junction box.

Circuit breaker installation

The modern installation of the switch is based on mounting it on a DIN rail or strip. This is the simplest and most effective attachment mechanism. Groups of circuit breakers, or single ones, must be installed according to the rules for the safe design of electrical installations in special shields that prevent dust from entering the machines, as well as accidental touch of a person to its conductive parts.

It is imperative to remember that all installation, connection and installation work must be done safely, which means with a complete shutdown and checking the absence of voltage. This activity can be done with any voltage probe or indicator. It should be remembered that these works are classified as hazardous work and can cause human death.

The setting of the trip units of the circuit breakers is carried out by the manufacturer, therefore it is better not to adjust this system in a domestic environment.

Connecting the luminaire to the switch

Connecting a switch to a lighting device is a simple process, the main thing is to remember one basic rule that it is installed on a phase wire, and not on a zero wire. To do this, with the power supply turned on, you need to determine which wire is phase. For this, special devices are used:

1. voltage indicators;
2. pointing screwdrivers.

In order to connect the switch, it is necessary to remove the supply voltage from this section of the circuit.

But it is also necessary to ensure that there is no connection of copper and aluminum wires by the twisting method, but only through a terminal block or connector. The combination of these two materials over time leads to poor contact between them due to oxidation that results from the chemical reaction of these elements. The switch can be:

1. One-key;
2. Two-key;
3. Three-key, etc.

In any case, the phase wire comes to them alone, and after that it diverges as a control for different lamps of the lamp. The twists in the junction boxes must be reliably and properly insulated so that a short circuit does not occur.

Lighting switches should be selected in accordance with the current, which depends on the power of the lamps. On all these elements and components of the electrical network, if you look closely, there are markings. For example, if you connect a light switch designed for 10 A, then the lamp current should not be more than this value, it may be less. Often the current is not written on the lamps, but only the power and voltage. The current will be equal to the power divided by the voltage. For example, if a 100 W lamp is connected to a 220 Volt network, then the current in its circuit will be approximately 0.45 A.

The correct choice, connection and installation of a circuit breaker and a lighting switch is a guarantee of durable and trouble-free operation of electrical equipment. And also in emergencies, overloads and short circuits, protection operation will protect the premises from fires.

Video about circuit breakers

(can also be called an automatic machine, a switch) - a switching device designed to supply email. current to the object and its automatic shutdown in case of malfunctions in the electrical network. Design and operation

To properly connect the machine to work, you need to understand its design and the principle of operation.

Sectional drawing of a circuit breaker with a thermal release

The main parts of the product are as follows:

• body;
• switching device;
• control mechanism (handle, button);
• arc extinguishing chamber;
• screw terminals (top, bottom).

The housing and control mechanism are made of durable plastic that does not support combustion. The switching device is both movable and fixed contacts. The pole of the machine is a pair of these contacts, which has its own arc chute. Its main purpose is to extinguish email. an arc that appears at the moment of breaking the contacts under load. It is a set of steel plates with a special profile shape. They are equidistant from each other and isolated from each other. The electric arc generated during the malfunction is attracted to these plates. Here it cools down and goes out. The number of pairs of contacts can be from 1 to 4.

For example, a two-pole circuit breaker has 2 moving and 2 fixed contacts. The machine has a position indicator: red means that the product is on, and green means it is off. This allows you to quickly navigate and find out what state the machine is in.

Outside the machine, only the handle, the screw clamps located above and below, and the indicator are visible. Everything else is inside the body of the device.

The housing has special jaws called a retainer, which allows the circuit breaker to be quickly mounted on a special rail called a DIN rail. In case of replacement of the product, the same lock allows you to quickly dismantle it: by loosening the fastening screws on the terminals of the machine, it is enough to slide the lock down. The machine can be easily removed from the rail. Today, such slats are an integral part of any electrical panel. Many modern elements of electronics and automation are manufactured specifically for installation on a DIN rail.

The mechanism that opens the circuit breaker when an emergency occurs is called a release. Each type of release has its own device.

The thermal release in its design has a special plate called bimetallic. It is made by pressing from 2 dissimilar metals that have different coefficients of linear expansion. The plate is connected to the electrical circuit in series with the load. During the operation of the device, the plate is heated by the current passing through it, and it bends towards the metal, which has a lower coefficient of expansion. When the current increases above the nominal (overload), its bending will lead to the disconnection of the machine. For this, a trigger mechanism is provided in the design.

The tripping of the switch is also influenced by the ambient temperature. Therefore, in some products, the response time is adjusted in accordance with this temperature. In any case, the higher the current value from the rated value, the faster the thermal release will trip. Some of them work in a matter of seconds.

Circuit breaker with magnetic release in section

A coil with a winding and a core is the magnetic release. The winding is made of insulated copper wire. Included in email the circuit is in series with the contacts - the load current moves along it. If it exceeds the set permissible value, then the magnetic field of the coil will move the core, and this, in turn, acts on the disconnecting device. This will open the contacts of the circuit breaker.

The device of the machine with a combined type of control

Some types of breakers provide a time delay in the event of a short circuit and are called selective. Such a product has a special panel where the breaker opening time is set. This makes it possible to turn off a specific section where the short-circuit occurred, and where other machines worked. As a result, there is no need to completely disconnect the object from the power supply; you can only turn off the area where the emergency situation has developed. As a rule, these are powerful devices with a semiconductor type release.

There may be no release in the design of the machine, and then it is called a switch-disconnector.

Machine selection

Before proceeding with the installation, it is necessary to choose the right product. How much to supply: one or several, at what capacity, which manufacturer? Do you need an introductory machine? Connect before or after the meter? These are the most frequently asked questions.

Each switch is characterized by the following parameters:

• rated current (indicated in A);
• working voltage el. networks (indicated in B);
• the number of poles;
• maximum short-circuit current;
• time-current characteristic (response time of the device, depending on the value of the flowing current - the limiting switching capacity (PKS)).

The last parameter is indicated in numbers, which mean at which current value the device will remain operational. In everyday life, products are used with numbers 4500, 6000 and 10000 A.

Manufacturers usually indicate all this directly on the device case, including the circuit diagram for putting into operation and the symbol of the switch.

Placing the technical characteristics of the machine on the body of the device

The choice of the switch is carried out according to the load power and the section of the connected wire. They are usually chosen according to 2 parameters: overload current, short-circuit breaking current.

Overload occurs when devices and devices are connected to the network, the total power of which will lead to excessive heating of the conductors and contact connections. Therefore, the machine, which will be installed in a specific circuit, must have a tripping current greater than or equal to the calculated one. It is determined by summing up the power of the electrical devices intended for use (indicated in the passport). Next, the resulting figure is divided by 220 (remember physics and Ohm's law) and the desired overload current is obtained. One more circumstance must also be taken into account: this current should not be greater than the current that can flow through the conductor.

Short-circuit breaking current - this is its value at which the circuit breaker trips. He is also calculated, and then selected according to the type of protection. It contains the values \u200b\u200bof the shutdown current in relation to the probable short-circuit current. This current depends on the type of load of the mains. In everyday life and for small objects, devices are used with the symbol B, C, and at the input - D (see the placement of the symbol in the figure).

Most often, in addition to the machines for each group line, the electrical circuit also includes an introductory machine, an RCD or a differential machine.

Connection diagram of protection devices in the switchboard

The diagram indicates the following main points, which are important to know:

• complete set of the switchboard (input automatic machine, electric meter, RCD, automatic machines from the running lines);
• paired operation of the introductory machine and the RCD (this is evidenced by the lower rated current of the RCD than that of the introductory machine);
• the place of installation of the RCD (should be close to the power supply input, therefore it is mounted immediately behind the meter);
• installation of one RCD protecting the entire electrical circuit (leakage current should not exceed 30 mA);
• when installing the RCD, the zero protective (PE - black lines) and the zero working conductor (N - blue lines) are separated;
• cross section of conductors and wire brand;
• how the phase conductor is connected to the main devices of the circuit (red lines on the diagram).

External view of the switchboard with installed devices for metering the consumption of electricity. energy and protection el. circuits are shown in the figure below:

Placement of protection elements and meter in the switchboard

Manufacturers

Circuit breakers are manufactured in many countries. The main requirement for this device is that it must be made of quality materials and have a long service life. The price of an automatic machine of the same power can vary in a fairly wide range and it depends on the manufacturer.

The highest quality machines are produced by the following companies:

• french: Legrand, Schneider Electric, Hager;
• slovak SEZ Krompachy;
• german: ABB, Moeller, Kopp;
• american General-Electric;
• russian: Kontaktor, KEAZ.

Mounting

Before installing the switch, it is necessary to clearly determine where to correctly connect the wires or power cables: from the top or bottom of the product, or, in other words, to moving or fixed contacts. And although many do not comply with this condition and connect without taking into account this factor, it is still more correct to turn to the PUE, which for electricians is the document whose instructions must be followed. It clearly says: the connection of the supply wire (cable) must be carried out to fixed contacts. They are located on top in all modern machines.

Installation cannot be carried out without tools and control devices. You must have:

• screwdriwer set;
• assembly knife;
• tester or screwdriver with indicator.

Single pole

Installation is carried out in single-phase networks, in which the input is made by 2 wires (usually these are old buildings): phase (L) and zero (PEN), i.e. made according to the TN-C system. The power wire is connected to terminal 1 of the machine, from terminal 2 through the counter it is distributed among the machines of specific groups. The zero supplying through the counter is fed to the zero bus PEN. This is clearly shown in the figure below.

Connection diagram of single-pole circuit breakers in the switchboard

Bipolar

Installation is carried out in single-phase networks, in which the input is carried out with 3 wires, one of which is a phase (L), the second is zero (N), the third is ground (PE), i.e. connection is carried out via TN-C-S or TN-S systems. Here, the supply wire is connected to terminal 1, zero to terminal 3 and is securely fastened. Terminal 2 is output, the phase passes through the meter. The input device, which is an RCD, distributes evenly power to the switches combined into separate groups. From terminal 4, which is output, zero passes through the electricity meter, RCD and is connected to the N bus. The wiring is schematically shown in Figure 10.

Connection diagram in the panel of two-pole circuit breakers

The passport for the machine indicates the requirements for connecting conductors to its terminals. The information must be carefully studied. This applies to both the cross-section and the type of connection of the conductors, as well as the length of the stripped part.

Usually, for machines used in everyday life, the wires are stripped of insulation to a length of up to 1 cm using a mounting knife. You should also pay attention to the color coding of the wires. White or brown color for the supply wire (phase), blue (blue, black) for the neutral conductor, yellow-green or green for the grounding conductor.

After stripping with a mounting knife, the bare part of the wire is inserted into the terminal clamp from above or below, depending on which conductor is connected (phase, earth or zero). Then they are securely fixed in the corresponding terminals with screws. You will need a screwdriver here. The reliability of the conductor attachment is checked by twitching. In the case of connecting a flexible wire to the circuit breaker, it is necessary to use special terminals, which makes the connection more reliable.

When connecting conductors to the machine, it is necessary to observe the following factors:

• insulation must not get under the terminal;
• do not tighten with great force, this can deform the case and, as a result, lead to device failure, malfunction or shortened service life.

In many cases, several circuit breakers are installed in the distribution board. Inexperienced electricians connect them with jumpers. This is permissible, but it is better to use a special bus. It is called a comb. It is usually cut to the required size, and then the phases are connected to the machines in the sequence provided for by the principal email. scheme.

External view of the connecting bus

Electrification

To correctly carry out the electrification of an object of any complexity, you need to perform the following steps:

• draw up an electrical diagram taking into account all the features of the wiring of a particular object;
• correctly determine the total power consumption;
• determine the number of electrical groups and the power of each group;
• decide on the place of installation of the switchboard and for how many modules it should be;
• select a metering device (electric meter);
• correctly connect outgoing and incoming lines;
• connect the shield to the networks of the energy supply company.

Connection. Video

You can find out about the electrical circuit for connecting circuit breakers from the video below.

All this can only be done by competent electricians who are well versed in the power supply of simple and complex objects. They know the modern electrical engineering base and are able to equip the electrical panel with everything necessary at minimal cost. In addition, based on years of experience, they can provide useful advice on saving energy and improving the energy supply of existing facilities.

The process of installing machines in the electrical panel is quite simple and does not take much time. The only problem is to do everything correctly, because when connecting wires, many novice electricians make small mistakes that can damage the device in a short period of time. In this article, we will look at how to connect a circuit breaker with our own hands, providing installation rules, basic errors and diagrams.

Typical installation errors

Most often, when, and in particular, connecting the machine, the following mistakes are made:

Another important point on which there are many discussions is whether it is possible to connect the machine in front of the electricity meter or is it done only after it? The answer is that it is possible, and even necessary, the main thing is to buy a special box, which is sealed by representatives of energy sales. Installing an introductory machine in front of the electric meter will allow for the safe replacement of the electricity control device both in a private house and an apartment.

That, in fact, are the rules for installing and connecting an electric machine with your own hands. Now let's move on to the main topic of the article.

Main process

So, in the initial position, we have an electrical panel in which the products will be installed, as well as all the wires (input and output to consumers).

Consider the instructions for dummies using the example of connecting a two-pole circuit breaker in the dashboard:

1. The first step is to turn off the electricity and check its presence using a multimeter or an indicator screwdriver. we provided readers!
2. The machine is installed on a special DIN-rail and latched into place with a latch. You can do without din reiki, but this is less convenient.
3. The conductors of water and outgoing conductors are stripped by 8-10 mm.
4. You need to connect the input zero and the phase to the two upper terminals (do not forget about the recommendations mentioned above).
5. Accordingly, outgoing zero and phase (those that go to electrical appliances, sockets and switches) are fixed in the two lower holes.
6. After that, the place must be manually checked for reliability. To do this, you need to carefully take the guide and move it in different directions. If the core remains in place, then the connection is reliable, otherwise be sure to tighten the screw again.
7. After all electrical installation, the robot is energized to the network and the functionality of the product is checked.

That's all the instructions for connecting a circuit breaker in a single-phase circuit. As you can see, there is nothing complicated, you just need to be careful. We also recommend that you read the video tutorial, in which the connection process is discussed in more detail:

Visual video instruction

Installation of a low-quality single-pole circuit breaker

Connection diagrams

Content:

Automatic switches, called in everyday life machines or switches, belong to the means of switching and are intended to supply electric current to any object. The main function of these devices is to automatically cut off the power supply in the event of an emergency and network failure. The machine protects the electrical circuit from short circuits, overloads and voltage drops in excess of the permissible value.

Which circuit breaker to install?

When calculating the rating of the circuit breaker, start from the cross-section of the wire, the temperature load, as well as how the wiring will be laid - hidden or open. Consider not the limiting current transmission, but "quiet", ie. there must be a good margin of safety, or, more simply, so that the conductor does not warm up due to the overrated rating of the machine. In another case, if the conductor has a large capacity, it is not worth underestimating the value of the machine - it will constantly knock it out.

Sectional circuit breakers are “set” on a plate called a din rail, built into the switchboard. Automatic switches are 1P (pole), 2P, 3P, 4P. The last two are installed in a three-phase network. In a single-phase network, a 2P machine is most often installed at the input.

The nominal current strength of the circuit breakers in everyday life: 2A, 6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, 63A.

Where are circuit breakers not installed?

On separate groups they put 1P, 2P is possible, but this is not economical both in terms of money and in the space of the panel room. It is known that in France, according to the rules and regulations, only two-pole switches are installed. This is not to say that they do not save space in the control room. The fact is that French double-pole switches are like our single-pole ones. Do not set the 1P circuit breaker to zero. It is not recommended to break the zero separately from the phase. All neutral conductors are attached to a common neutral bus. You can break zero simultaneously with the phase, in this case you need to put a 2P machine.

To effectively protect the electrical circuit of your home, it is worth considering replacing the fuses or plugs. for a safer, more reliable and cost-effective circuit breaker.

The process of installing machines in the electrical panel is quite simple and does not take much time. The only problem is to do everything correctly, because when connecting wires, many novice electricians make small mistakes that can damage the device in a short period of time. In this article, we will look at how to connect a circuit breaker with our own hands, providing installation rules, basic errors and diagrams.

Typical installation errors

Most often, when, and in particular, connecting the machine, the following mistakes are made:

Another important point, on which there are many discussions, is it possible to connect the machine in front of the electricity meter or is it done only after it? The answer is that it is possible, and even necessary, the main thing is to buy a special box, which is sealed by representatives of energy sales. Installing an introductory machine in front of the electric meter will allow for the safe replacement of the electricity control device both in a private house and an apartment.

That, in fact, are the rules for installing and connecting an electric machine with your own hands. Now let's move on to the main topic of the article.

Main process

So, in the initial position, we have an electrical panel in which the products will be installed, as well as all the wires (input and output to consumers).

Consider the instructions for dummies using the example of connecting a two-pole circuit breaker in the dashboard:

1. The first step is to turn off the electricity and check its presence using a multimeter or an indicator screwdriver. we provided readers!
2. The machine is installed on a special DIN-rail and latched into place with a latch. You can do without din reiki, but this is less convenient.
3. The conductors of water and outgoing conductors are stripped by 8-10 mm.
4. You need to connect the input zero and the phase to the two upper terminals (do not forget about the recommendations mentioned above).
5. Accordingly, outgoing zero and phase (those that go to electrical appliances, sockets and switches) are fixed in the two lower holes.
6. After that, the place must be manually checked for reliability. To do this, you need to carefully take the guide and move it in different directions. If the core remains in place, then the connection is reliable, otherwise be sure to tighten the screw again.
7. After all electrical installation, the robot is energized to the network and the functionality of the product is checked.

That's all the instructions for connecting a circuit breaker in a single-phase circuit. As you can see, there is nothing complicated, you just need to be careful. We also recommend that you read the video tutorial, in which the connection process is discussed in more detail.

A modern switchboard in a home must be equipped with protective equipment such as a circuit breaker. To correctly connect the machine in the dashboard, you need to know the rules and features of the procedure.

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What is a circuit breaker and what is it for?

The circuit breaker is a small lever mounted in a panel. The principle of its operation is that it allows you to turn off the electricity supply manually or automatically.

Automatic shutdown is necessary in cases:

• short circuit;
• overload of electric current supply.

In other words, such devices cut off electricity at a current exceeding the short-circuit power.

Classification

Before buying a circuit breaker, an electrician must decide on the number of poles. This indicator depends on the phases of the network.

The machines are subdivided according to the number of poles:

• single-pole;
• bipolar;
• three-pole;
• four-pole.

Single-pole and double-pole machines are installed in a single-phase network. Three-pole and four-pole are suitable for a three-phase network.

The growmir channel talks about self-installation and connection of the machine to the bagger.

How to choose a machine?

The correct choice of a switchboard machine is a guarantee of balanced operation of the entire electrical circuit in an apartment or other room.

• Legrand;
• Hager;
• Merlin Green;
• Schneider Electric;

When buying a circuit breaker, experts recommend paying attention to the labeling, which contains all the information about the product.

When planning the choice of a device, you need to pay attention to the parameters:

1. The value of the rated current. The higher it is, the more voltage is required to automatically turn off the machine. The parameter is selected based on the cable cross-section, and not on the load power.
2. Number of poles. This parameter is selected based on the number of phases. The number of slots for the machines corresponds to the number of poles.

Do-it-yourself installation of a circuit breaker in an electrical panel

When installing the machine in an electrical panel, you need to be guided by the rating of the device and the cable cross-section, which is determined based on the maximum wiring load.

Before installation, evaluate:

• rated mains voltage;
• maximum current;
• rated current.

To calculate the load, add up the total power of energy consumers (sockets, household appliances, etc.) and calculate the current power according to the formula below. Knowing this parameter, they decide which machines to connect.