Automatic switches: selection, connection, maintenance. Types and principle of operation of electrical automata Electric shutdown machine

The electrical machine, or the circuit breaker, is a mechanical switching device, by means of which it is possible to manually de-energize the entire electrical outlet or its specific area. You can do this in the house, apartment, in the country, in the garage, etc. Moreover, such a device is equipped with the function of automatic shutdown of the electrical cable when emergenial situations occur: for example, in the event of a short circuit or overload. The difference of such circuit breakers from ordinary fuses is that after responding, you can turn on the button again.

Let's talk about how to choose automatic machines: electrical machines exist in a large manifold, which requires accounting for a number of a number of factors when purchasing them.

Do you need such a machine? It is necessary to give an affirmative answer. A working circuit breaker will protect your room from various unpleasant situations, including:

• fires;
• electric shocks;
• wiring damage.

So, when choosing a machine, as we noted, several indicators should be taken into account. Consider them in order.

Basic criteria for choosing

Short circuit current

This indicator must be considered immediately. It means that maximum current value at which the electrical machine will work and open the chain. Here the choice is not great, as there are only three options:

• 4.5 ka;
• 6 ka;
• 10K.

When choosing, you should be guided by theoretical probability of the occurrence of a strong short circuit current. If there is no such probability, it will be enough to purchase 4.5 cars.

Current machine

Accounting for this indicator is the next step. We are talking about the necessary nominal value of the operating current of the electrical machine. To determine the operating current, you need to be guided by the power that is supposed to be connected to the wiring, or by the valid current value (the level that will be maintained in normal mode).

What do you need to know when determining the parameter under consideration? It is not recommended to use automata with an overestimated operating current. Simply, in this case, the automatic during overload will not turn off the power, and this can cause thermal destruction of the insulation of the wiring.

This is perhaps the simplest indicator. To select the number of poles at the switch, you need to proceed from how it will apply.

So, a single pole machine is your choice if you need to protect the wiring, which goes out of the electrical panel to sockets and lighting chains.

The two-pole switch is used when it is necessary to protect all the wiring in an apartment or a house with single-phase power.

The protection of three-phase wiring and load is provided by a three-pole automatic machine, and the four-pole are used in order to protect the four-wire power supply.

Characteristics of automatic

This is the last indicator to be needed to pay attention. The time-current characteristic of the circuit breaker is determined by the loads that are connected to the protected line. When choosing, the characteristic is taken into account: the operating current of the chain, the rated current of the machine gun, the cable bandwidth, the operating current of the switch.

• In the event that it is necessary to connect small launchers to the power line, i.e. Electrical devices characterized by a small difference between the operating current and the current, which occurs when turned on, preference should be given to the response characteristic of B.
• Finally, there is another characteristic - D. Your choice should be stopped on it if you are supposed to connect powerful devices with high startpoints. What devices are we talking about? For example, about the electric motor.

The final stage of choice

These are the main indicators that should be considered when choosing an automatic switch. Accordingly, if all the necessary data you will be known, the choice will not be difficult. It will only be taken into account the latest criterion - manufacturer of the machine. What does it affect?

• obviously, the cost. Indeed, there is a difference. Thus, the well-known European brands offer their circuit breakers at a price, which is twice the cost of domestic analogues and three times the price of instruments from southeastern countries;
• also, the choice of a specific manufacturer depends on the presence of either the absence of a switch with well-defined indicators in the warehouse.

Another useful way to choose an electrical machine is offered on the video below:

Modern power supply of private houses and apartments are not recommended to do without protective automata. They provide security and guarantee a long service life of the wiring. About the choice of automatic protection and we will talk in this article.

The main task of the circuit breaker is to protect the wiring from overheating and insulation from melting. And it does this by turning off the power in those moments when the conductor heats up to critical temperatures due to the connection of the excessive power load. The second task of the packet is to turn off the line at currents of the KZ (short circuit). The goal is the same - to save the wiring from destruction.

Timely shutdown of nutrition in problems is very important, as it prevents the wiring and fire. Therefore, the choice of automatic protection is the responsible task. You need to choose according to the rules, and not according to the principle "to less often disconnected." This method can lead to a fire. In general, the choice of a protection machine is carried out in three parameters:

• denomination;
• turning off (cut-off);
• type of electromagnetic discharge (time-current characteristic).

Each parameter is important and selected depending on the load connected to the specific line, the location of the wiring relative to the distribution substations.

Types of circuit breakers

Protection machines are released for single-phase and three-phase chains. For a single-phase network there are two types of packeting - single-pole and bipolar. Only phase wire is connected to one-pole and, when triggered, only the phase is turned off. Such machine guns are recommended to put in houses and apartments in rooms with normal operating conditions. Usually they are installed on the lighting lines, socket groups that are located in residential rooms, corridors, kitchens.

Automatic switches - single pole, two-pole and three-pole

The two-pole circuit breakers are breeding and a phase and zero wire. It breaks both chains. The degree of protection is much higher as the disconnection is complete, not partial. Such an automatic will ensure security even if the voltage has fallen on the zero conductor. Two-pole machines recommend putting on the selected lines to which powerful household appliances are connected. They are also put on premises with complex operating conditions. These include bathroom, swimming pool, sauna.

For three-phase networks, three-poly and bipolar circuit breakers are used. All three phases are created on three-pole. Accordingly, they are turned off all at the same time. Such packagers put on entering a house or apartment, as well as on the line to which three-phase consumers are connected - the cooking panel, the oven and other similar technique. For the same consumers, you can install four-pole circuit breakers. They will also turn off the zero wire.

Other power supply lines on which one of the phases is used are bipoly packets. The simultaneous disconnection of the phase and zero is more preferable. And only on the line of lighting can be installed single-pole.

Selection of load current protection

When planning wiring, the main task is to select the rating of the circuit breaker. When passing the current through the conductor, it begins to warm up. The larger current passes through the conductor of the same section, the more heat allocated. The task of the circuit breaker is to turn off the power until the current consumed will be higher than it is permissible. Therefore, the rating of the automatic protection must be less than the permissible wiring current.

Ratings of circuit breakers are standardized: 6 A, 10 A, 16 A, 20 A, 25 A, 32 A, 40 A, 50 A and 63 A. In practice, six and ten ampere options are not yet used yet - equipment in our homes becomes More and more small cross sections do not cope with the load.

Choosing a nominal

Select the circuit breaker is not loaded, not by power connected devices or over. These parameters are taken into account when selecting a conductor cross section. And the choice of automatic protection is made depending on the cross section of the conductors. There is a special table in which the permissible load currents are indicated and the recommended nominal protection machine. We simply use the table: find the desired section, in this row, look for the nominal protection machine. Everything.

Section of core cable	Recommended Nominal Protective Machine	Machine operation current	Permissible long load current	Maximum load power	Application area
1.5 mm2	10 A.	16 A.	19 A.	4.1 kW	Lighting and alarm
2.5 mm2	16 A.	25 A.	27 A.	5.9 kW	Outlets, electric warm floor
4 mm2.	25 A.	32 A.	38 A.	8.3 kW	Water heaters, air conditioners, washing and dishwashers
6 mm2.	32 A.	50 A.	46 A.	10.1 kW	Electric stoves, oven
10 mm2	50 A.	63 A.	70 A.	15.4 kW	Inputs in the house, apartment

How everything works

Looking at the table, the question arises: why the nominal automaton is so smaller than the maximum permissible current load. The answer in the mechanics of the operation of the circuit breaker. It turns off only when the current in the circuit is 13% higher than the operation current.

For example, an automatic 10 A will work when the current of the current in the chain is 16 A + 13% (2.08 a) \u003d 18.08 A. That is, there is a small gap to the value of the permissible load. This clearance is necessary to ensure the integrity of the isolation.

Modern system of power supply at home or apartment is not without circuit breakers

What will happen if the wire is 1.5 mm2 to put an automatic machine on 16 A. because its denomination is below the permissible load current? Let's count. The current in which the packet will work - 25 A + 3.25 A (13%) \u003d 28.25 A. It is higher than permissible long load current. Yes, it will be rarely disconnected, but after some time the insulation melts and the wiring will have to be changed. Therefore, the choice of the protection machine is better to produce on this table, but not for a long time permissible current.

Selection by load

If the power line is laid with a power reserve, and the load on it is far from the limit, you can put an automatic with a lower rating. In this case, it will protect not so much a line from overheating as technique from CW currents.

Selection of the load power protection automaton - incorrect idea

The choice of the nominal protection machine in this case can also be done on the same table. Only for the starting point we take the load capacity. But repeat again. This is if the line parameters are withstanding a much larger load than exists.

View of the electromagnetic discharge (shutdown curve)

The following parameter for which the choice of protection automaton is selected is the type of electromagnetic separator. He is responsible for the delay, which occurs when triggered. It is needed to avoid false disconnections during the start of motors of various equipment.

When you turn on the engine of the refrigerator, dishwasher or washing machine, the current in the chain increases briefly. This phenomenon is called starting currents, and they can exceed working consumption 10-12 times, but last very long. Such short-term harm increase does not cause. So, the electromagnetic discrete must have a delay that allows you to ignore these starting currents. This characteristic is displayed by Latin letters B, C, D. This letter is placed in front of the nominal protection machine (Mi photo). The choice of a protective protection on this feature is easy. It is only necessary to know the nature of the planned load:

Actually, the choice of the circuit breaker in this case is simple. On the lighting line, it is enough to install the automata category B, which can be set to the rest.

Select the degree of protection against currents KZ (cut-off current)

The second function of the protective circuit breaker is to turn off the power when the currents appear that occurs with a short circuit (KZ). The protection machines are designed for different values \u200b\u200bof these currents, and the characteristic that displays it is the disconnecting ability or cut-off current. It shows, with what CZ current automatic will still remain in working condition. The fact is that the packet works not instantly, because there is a trigger delay to ignore launching overloads. During this delay, contacts can be melted and the device will be inoperable. So, the cut-off current or the disconnecting ability shows which currents can make contacts without compromising performance.

In the household power grid, protective automata with three degrees of protection against COP currents are used: 4500 a, 6000 A, 10,000 A. on the device of the device, these numbers are affixed in the frame slightly below the nominal automaton. For the price, the difference is quite noticeable, but it is justified - in more "persistent" packets use refractory materials, and they are much more expensive.

How to choose an automatic protection in this case? The choice depends on the location of the network relative to the substation. If the house or apartment is located near, the CZ currents can be very large, therefore the disconnecting ability should be no less than 10,000 A. If the household is in rural areas, the network there is old and / or the feed occurs on the air network, enough automaton with a disabling capacity of 4500 A . In all other cases put on 6000 A.

Cost protection

The degree of protection of the case is in characteristics. It is indicated by Latin IP letters and two digits. The first digit shows how much the device is protected from dust penetration and foreign objects. The lowest protection (absent) is 0, the highest level - 6 (full protection against long-term exposure). The second digit displays the protected from the effects of moisture. Without protection - 0, it can be in water for some time - 8. Decryption of numbers is given in the table.

If the electrical shield is installed in the apartment, in a dry room, it is enough to protect the IP20 protection. On the staircases, a higher degree of protection is already desirable. At least IP32. If the machine is installed on the street, it is worth putting no less IP55.

Dear or cheap?

In stores and markets there are two price categories of protective automata. One part is produced by famous brands and has a very solid price tag. These are such a Schneider Electric (Electric Schneider), ABB, Legrand and others. These brands have long been on the market, have European roots and a well-established reputation. The quality of products is always at the height, so those who do not like to risk and can afford to spend on the assembly of the electric booster solid money, prefer to buy products with these manufacturers.

Next to them usually lie the same automata, but they are 2-5 times less. This is IEK (IEK), EKF (ECF), TDM (TDM), DEKRAFT (Dercaf), etc. These are Chinese automata, but produced at the factories. Some brands (the same dekraft) have European roots (in this case, Germany), but production facilities in China. These brands are also considered not bad, show stable results. So for those who try not to spend extra money - this is a good option. Affordable price and good quality.

What should not be done, so it is to buy products of unknown manufacturers. Even if the price they have a very attractive and seller you praise them very much.

There is also the purchase of famous brands pitfalls: too much divorced fakes. Moreover, they sell them almost at the same price as the original and on external signs to distinguish them very difficult. The only thing that can be navigated is less weight. In fakes, there are fewer metal, there may be any items. Due to this, weight is less. There may be an error in applying inscriptions, sometimes paints of other shades are used. To see all this, you must first study all the nuances of originals on official sites, and even better to hold them in your hands.

The main difference between these switching apparatuses from all other similar devices is a comprehensive combination of abilities:

1. Long maintain nominal loads in the system due to reliable transmission through its contacts of powerful electricity flows;

2. Protect the working equipment from accidentally emerging faults in the electrical circuit due to the rapid removal of power from it.

Under normal operating conditions, the operator can manually switch the load with automatic switches, providing:

different power schemes;

changing network configuration;

conclusion of equipment from work.

Emergency situations in electrical systems occur instantly and spontaneously. A person is not able to quickly react to their appearance and take measures to eliminate. This feature is covered with automatic devices embedded in the switch.

In the energy sector, it is customary to divide electrical systems by type of current:

constant;

variable sinusoidal.

In addition, there is a classification of equipment for the magnitude of the voltage on:

low-voltage - less than thousands of volts;

high-voltage - everything else.

For all types of these systems, their circuit breakers are created for multiple work.

Chains of alternating current

By power transmitted electricity, the circuit breakers in the AC circuits are conditionally divided into:

1. Modular;

2. in the cast case;

3. Power air.

Modular structures

Specific performance in the form of small standard modules with a width of multiple 17.5 mm determines their name and design with the possibility of installing on a DIN rail.

The internal device of one of the similar circuit breakers is shown in the picture. Its housing is fully manufactured from a durable dielectric material excluding.

The feed and exhaust wires are connected to the upper and lower terminal clamp, respectively. For manual control of the switch, a lever with two fixed positions is installed:

the top is designed to supply current through a closed force contact;

lower - ensures the break of the power chain.

Each of such automata is designed for long-term operation at a certain value (IU). If the load becomes larger, then the power contact occurs. For this inside the case there are two types of protection:

1. thermal release;

2. Current cutoff.

The principle of their work allows you to explain the spectacular characteristic, expressing the dependence of the time of the protection of the protection against the current or accident passing through it.

The graph presented in the picture is given for one particular circuit breaker, when the cut-off area is selected in 5 ÷ 10 times the nominal current.

When initial overload operates a heat release, made of, which, with an enlarged current, gradually heats up, bends and affects the disabled mechanism not immediately, but with a certain time delay.

In this way, it allows small overloads associated with a short-term connection of consumers, it is expected and eliminating unnecessary shutdowns. If the load will ensure the critical heating of the wiring and isolation, then the power contact occurs.

When an emergency current occurs in the protected chain, which can burn the equipment with its energy, the electromagnetic coil comes into operation. It impulse at the expense of the load of the load throws the core to the disconnecting mechanism in order to instantly stop the exhaust mode.

The graph shows that the higher the currents of short circuits, the faster there is a shutdown by an electromagnetic release.

On the same principles, the household fuse is automatic steam.

When the high current breaks, an electric arc is created, the energy of which can burn contacts. To exclude its action in circuit breakers, an extinguishing chamber is used, separating arc discharge on small streams and quenching them by cooling.

Multiplicity of cutoffs of modular structures

Electromagnetic releasers are configured and selected under work with certain loads because when starting, they create different transient processes. For example, during the inclusion of different lamps, a short-term flow of current due to the changing resistance of the filament may approach the three crown of the nominal value.

Therefore, for the outlet group of apartments and lighting chains, it is customary to select automatic switches with a streaming characteristic of the "B" type. It is 3 ÷ 5 IN.

Asynchronous motors when promoting a rotor with a drive causes large overload currents. For them, machine guns are selected with the characteristic "C", or - 5 ÷ 10 IU. Due to the reserves of time and current, they allow the engine to spin and guarantee the operating mode without excessive shutdowns.

In industrial production on machines and mechanisms, loaded drives connected to engines that create more enlarged overloads are found. For such purposes, the automatic switches of the characteristics "D" are used with a par value of 10 ÷ 20 IU. They have proven themselves well when working in schemes with active inductive loads.

In addition, automata has three more types of standard time characteristics that are used for special purposes:

1. "A" - in long wiring with active load or protection of semiconductor devices with a value of 2 ÷ 3 IU;

2. "K" - for pronounced inductive loads;

3. "Z" - in electronic devices.

In technical documentation, different manufacturers have multiplicity of cut-off for the last two types may differ slightly.

This class of devices can switch large currents than modular designs. Their load can reach up to 3.2 kiloamum.

They are manufactured according to the same principles as modular designs, but, taking into account the increased requirements for passing an increased load, they are trying to give relatively small dimensions and high technical quality.

These automata are designed to safely work at industrial facilities. According to the value of the rated current, they are conditionally divided into three groups with the possibility of switching loads up to 250, 1000 and 3200 amps.

Constructive execution of their hull: three- or four-pole models.

Power switches

They operate in industrial installations and operate with currents of very large loads up to 6.3 kiloampers.

These are the most complex devices of low-voltage equipment. They are used to work and protect electrical systems as introductory and exhausting devices for enhanced power distribution settings and to connect generators, transformers, capacitors or powerful electric motors.

A schematic image of their internal device is shown in the picture.

It uses already a double power supply breaking and exhaust cameras are installed with grilles on each side of the shutdown.

In the work algorithm, the inclusion coil, a closing spring, a springs platform motor and automation elements. To control the flowing loads, a current transformer with a protective and measuring winding is built.

The automatic switches of high-voltage equipment belong to very complex technical devices and are made strictly individually for each class of voltage. They are used, as a rule.

These are presented:

high reliability;

security;

speed;

ease of use;

relative silent when working;

optimal cost.

Loads that are torn during emergency disabling are accompanied by a very strong arc. It uses various methods, including a chain gap in a special environment.

This switch includes:

contact system;

exhausting device;

current parts;

isolated case;

drive mechanism.

One of these switching devices is shown in the photo.

For high-quality operation of the scheme in such structures, except for the operating voltage, take into account:

the nominal value of the load current for reliable transmission in the on state;

the maximum short circuit current on the valid value, which is able to withstand the disconnecting mechanism;

the permissible component of the aperiodic current at the time of the division of the scheme;

opportunities for automatic re-inclusion and provision of two CPV cycles.

According to arc harvesting methods during disconnection, the switches are classified on:

oil;

vacuum;

air;

elegazovy;

autogas;

electromagnetic;

autoinnevatic.

For reliable and convenient operation, they are supplied with a drive mechanism, which can use one or more types of energies or combinations:

sprout;

raised cargo;

compressed air pressure;

solenoid electromagnetic pulse.

Depending on the conditions of application, they can be created with the ability to work under voltage from one to 750 kilovolt inclusive. Naturally, they have a different design. Dimensions, automatic and remote control capabilities, protection defense for safe operation.

Auxiliary systems of such circuit breakers may have a very complex branched structure and placed on additional panels in special technical buildings.

DC circuits

These networks also work a huge number of circuit breakers with different capabilities.

Electrical equipment up to 1000 volts

Here we are massively introduced modern modular devices that have the ability to mount on a DIN rail.

They successfully complement the classes of old machines of type, ae and other similar, which were fixed on the walls of the shields with screw connections.

Modular DC designs have the same device and principle of operation, as their analogues on alternating voltage. They can be performed by one or more blocks and are selected by load.

Electrical equipment above 1000 volts

High-voltage circuit breakers for DC are operated on the installations of electrolysis production, metallurgical industrial facilities, railway and urban electrified transport, energy enterprises.

The main technical requirements for the operation of such devices correspond to their analogues on alternating current.

Hybrid switch

Scientists of the Swedish-Swiss company ABB managed to develop a high-voltage DC switch, combining two power structures in its device:

1. Elegazine;

2. Vacuum.

It was called a hybrid (HVDC) and uses the technology of consistent arc cleaning immediately in two environments: sulfur hexafluoride and vacuum. For this, the following device is collected.

A voltage is supplied to the top tire of the hybrid vacuum switch, and from the lower tire of the Elegazovoy - removed.

The strengths of both switching devices are connected sequentially and managed by their individual drives. In order for them at the same time, a synchronized coordinate operation management device is created, which transmits the command to the control mechanism with independent power to the fiber optic channel.

Due to the use of high-precision technologies, construction developers managed to achieve consistency of the actions of the actuators of both drives, which is laid in a period of less than one microsecond.

The switch control comes from the relay protection unit built through the repeater in the power line.

The hybrid switch made it possible to significantly increase the efficiency of composite email and vacuum structures through the use of their joint characteristics. It was possible to realize the benefits of other analogues:

1. The ability to reliably turn off the currents of the KZ with high-voltage voltage;

2. The possibility of a small effort to carry out the switches of power elements, which made it possible to significantly reduce the dimensions and. Accordingly, the cost of equipment;

3. Availability of the execution of various standards for creating structures operating in a separate switch or compact devices on one substation;

4. The ability to eliminate the consequences of a rapidly increasing regenerating voltage;

5. The ability to form a basic module to work with voltages to 145 kilovolts and above.

A distinctive feature line is the ability to break the electrical chain for 5 milliseconds, which is practically impossible to perform other structures with power devices.

The hybrid switching device is marked among the ten best developments for the year according to the MTI Technological Review (Massachusetts Institute of Technology).

Other manufacturers of electrical equipment are engaged in similar studies. They also achieved certain results. But ABB is ahead of them in this matter. Its guide believes that when transmitting the electricity of the AC, its large losses occur. They can be significantly reduced using high-voltage voltage chains.

Topic: Which types are divided by electro-automatics, their types and classification are divided.

The circuit breaker is an electrical device, the main purpose of which is to make the switching of its operating state when a certain situation occurs. Electric machines combine two devices in themselves, it is a regular switch and magnetic (or thermal) release, whose task is the timely rupture of the electrical circuit if the threshold value of the current force is exceeded. Circuit breakers, like all electrical devices, also have different varieties that they shared them on certain types. Let's get acquainted with the main classifications of circuit breakers.

1 »Classification of automatic machines by the number of poles:

A) single-pole machines

b) single-pole machines with neutral

c) bipolar automata

d) three-pole machines

e) three-pole machines with neutral

e) four-pole machines

2 "Classification of machine guns by type of release.

The design of various types of circuit breakers, usually includes 2 basic types of releases (swindings) - electromagnetic and thermal. Magnetic serve for electrical protection against short circuit, and thermal openingors are intended mainly to protect electrical circuits on a certain overload current.

3 "Classification of automatic transduction machines: In, s, d, (a, k, z)

GOST R 50345-99, at the current instantaneous trip, the automata are divided into such types:

A) type "b" - over 3 in to 5 in inclusive (in is the rated current)

b) type "C" - Over 5 in to 10 in inclusive

C) type "D" - Over 10 in to 20 in inclusive

Machine manufacturers in Europe have a slightly different classification. For example, they have an additional type "A" (over 2 in to 3 in). Some manufacturers of circuit breakers also have additional shutdown curves (AVU automata with k and z curves).

4 »Classification of automatic machines by the clan in the chain: permanent, variable, both.

Nominal electric currents for the main circuits are selected from: 6.3; ten; 16; twenty; 25; 32; 40; 63; 100; 160; 250; 400; 630; 1000; 1600; 2500; 4000; 6300 A. Also additionally produced automata for nominal currents of the main electrical caps of automata: 1500; 3000; 3200 A.

5 "Classification for the presence of currentization:

a) current-limiting

b) untranslanting

6 »Classification of automatic machines by types of release:

A) with a maximum current release

b) with an independent release

c) with minimal or zero voltage release

7 »Classification of automata according to the timing characteristic of time:

A) without time

b) with a time delay independent of current

c) with time delay back dependent

d) with a combination of specified characteristics

8 »Classification by availability of free contacts: with contacts and without contacts.

9 "Classification of automata according to the method of connecting external wires:

A) with rear addition

b) with front addition

c) with combined accession

d) with universal joining (and front and rear).

10 "Classification of the type of actuator: With manual, with motor and spring.

P.S. Everything has its own varieties. After all, if only one unity in my only copy was existed, it would be at least just boring and too limited! Thus, the variety and it is good that you can choose exactly what the maximum matches your needs.

The electrical network is a system that includes inputs, wires, current consumers, as well as switching equipment. Installing circuit breakers Provides network protection as a whole and individual consumers in emergency situations where the current parameters go beyond normal values \u200b\u200b(KZ, voltage jumps, changing the direction of current and so on). In addition, they allow you to fulfill infrequent commutation of consumers remotely or in manual mode (6-30 cycles of inclusion / disconnection per day).

Care of electric equipment

Evolution and fundamental device of circuit breakers

The history of the electric device began long before the emergence of the first commercial power grids. Thus, the principle of operation of the circuit breaker was opened back in 1836 by American scientist Ch. G. Paddage, but the modern design was patented only in 1924 by the Swiss company Brown, Boveri & Cie. Since then, each machine includes the following elements:

• contact block;
• neutralization chamber (arc) chamber;
• facilitator of the following types: thermal, electromagnetic, electronic, microprocessor;
• control mechanism: manual, spring or driven;
• the mechanism of free discharge.

Currently, a lot of electrical appliances are produced, what is the illustration of which serve characteristics of circuit breakersthat provide reliable switching and protection of power grids and consumers of any complexity and power in any operating conditions. The number of models of these devices of different manufacturers is not calculated.

Products of leading companies Siemens, Andeli, Schneider, whose products on the electrical engineering market are presented in the catalogs "Skat Technology" catalogs. Here you can see automatic switches in the photoand also familiarize yourself with their main characteristics and installation methods. If you are not a professional in electrical engineering, we recommend using the help of our specialists, which can be obtained including in online mode.

For those who are interested in how the circuit breaker works, we will give a short explanation. Each machine has settings to certain current parameters and heating of conductors. These settings are provided by the sensitivity of the solenoid solenoid of the current and the thermal relay with screw control (calibration). If during the network of the network, the parameters go for the installed framework, the chain breaks and de-energize consumers.

Classification of circuit breakers

For the classification of electrical apparatus, there are regulatory documents in which the technical and operational requirements for them are set out. Classes of circuit breakers Domestic and foreign production are determined in accordance with such documents:

• GOST 9098-78;
• GOST 14255-69;
• GOST R 50345-2010;
• GOST R 50030.2-99;
• IEC 60898-95;
• EN 60947-2;
• EN 60898.

In accordance with domestic regulatory documents, the classification of automata is carried out in 12 parameters that are taken into account dozens of operational characteristics of the devices. Quantitative and qualitative values \u200b\u200bof these parameters determine the purpose of the circuit breaker and the permissible conditions for its operation.

The main classification parameters of circuit breakers

The higher the level of the architecture of the power grid, the more difficult it is to select protection and management equipment to it, since you have to take into account a large number of different parameters of work. To achieve the desired result, it is necessary to carry out engineering calculations of all parameters so that the selection of the circuit breaker and other electrical apparatus ensures the reliable and secure operation of the network. The list of main characteristics of automata is as follows:

• nominal currents of the main chain and releasers -, respectively, 6.3-6300 (only 22 nominal) and 15-3,200 amps (only 12 denominations);
• constructive design - air or DC (800-6300 A), in a cast case or MCSB (10-2500 A), modular or MCV (0.5-125 A) automata;
• the number of poles of the main chain - from one to four;
• the presence or absence of current restrictions;
• types of release: zero, minimum, independent, maximum;
• presence or absence of contacts for connecting secondary chains;
• method for connecting input / conclusions: front, rear, combined, universal;
• mounting method: stationary, roll-out (on DIN rail), on connectors;
• type of cutoff: Normal, selective, instantaneous;
• type of drive: manual, spring, with propulsion (electromagnet, pneumatics, etc.);
• normal or secure execution.

The listed characteristics have their own designation or quantitative expression. For example, the shutdown curve of the circuit breaker is a graphical reflection of the reciphepter to the cut-off. It indicates with what the value of the nominal current "IN" is triggered the device. For this parameter, foreign production products are divided into 6 groups (types):

• A - 2-3 in;
• B - 3-5 in;
• C - 5-10 in;
• D - 10-20 in;
• Z - 2-4 in;
• K - 8-14 in.

The triggering class of automatic switches of domestic production is denoted by letters B, C and D, since our industry does not produce the products of other types. In turn, the velocity of the cut-off automata is divided into normal (0.02-1 sec.) And high-speed or instantaneous (less than 0.005 seconds). Selectivity of circuit breakers Indicates the ability to establish different cut-off time with an excerpt 0.25-0.6 seconds for subordinate electrical apparatus.

The machines of this type have the main and additional work chains, which allows you to turn off the emergency plot of the power grid controlled by the subordinate apparatus, and keep the current supply to the remaining consumers. The time range of speed and selection processes also reflect curves circuit breakers. The operation of protection devices occurs not only by current, but also by heat of wires, which is provided by a thermal relay. Simply put, the electromagnetic release reacts to current consumption, and the thermal relay is to heat the wiring.

It is from the configuration of the last depends on the speaker characteristic of the circuit breaker. The thermal load value should not exceed the nominal value for the wires of a certain section by more than 1.45 times. It is determined taking into account the method of laying wires and a total load. Depending on the set setting, the thermal relay can work instantly or maintain a network performance for a certain time, but no more than an hour.

On the importance of timely response of protection equipment

From the above data, it is clear how important the operation time of the circuit breaker is. The minimum value of this indicator is necessary for powerful industrial equipment. Here you usually use the class D devices with instantaneous discharge. For domestic needs with a stock, there are enough machinery of a class C of normal discharge.

The exceptions make up worn networks and particularly sensitive current consumers where the Class A and B machines should be used, in which the minimum response time of the circuit breaker does not only provide protection, but also prevents the wiring fire. By the way, the state of the latter is often determining when choosing electrical equipment. If the wire section does not match the load on the network, the thermal characteristic of the operation of the circuit breaker will prevent its normal operation.

Reflection of the characteristics of electrical equipment in its marking

For electrical products, it is characteristic of the use of the most important performance in the marking of products. For lighting lamps, it is consumed power and light strength. Marking of circuit breakers It is much more complicated, in the name of the product you can squeeze the minimum of information. This is usually the nominal operating voltage. Therefore, the labeling symbols are applied to the vessel of the machine:

• the class of current restrictions is indicated by a number placed inside the square; The number of poles is displayed by an icon;
• the class or category of application of circuit breakers is displayed together with the value of the rated current - for example, "C16";
• the maximum permissible value of the operation current, at which the risk of damage to the machine is excluded in the rectangular frame.

The listed information in the product marking is enough to determine how to choose / select an automatic switch in full compliance with the power parameters. However, with independent acquisition of the device, it is easy to make a mistake, if you do not take into account the performance characteristics and load values. For example, the operating parameters of open and closed wiring, copper and aluminum wires differ significantly.

If you specify a question how to choose / select an automatic power switch, it should be borne in mind that the copper wire with a cross-section of 4 mm, laid by an open manner, withstands the load of 9 kW. The same wire with a closed wiring will withstand 5.9 kW. It is clear that the power of the current consumer should not exceed the possibility of wiring.

Similarly ratings of circuit breakers Must be less than the corresponding network parameters. Otherwise, the risk of overloading the power grid up to the ignition of the wiring, to which the automatic simplicity does not react. In order to avoid such a situation, preliminary calculations are needed, which will provide a balance between current consumers, wiring and means of protection and management. Those who are interested in the question how to choose a circuit breaker for home, We will give advice: the nominal value of the device choose the passage of the wiring (cross section and material of the wires, as well as the method of their gasket).

Basic rules for connecting the circuit breaker

The competent device of the architecture of the power grid allows for an order to increase their reliability. Currently, we use the mass of household appliances and technology, including having significant power. The old posting of the Soviet sample was not designed for such loads, so the consumers often arise a question how to calculate the current circuit breaker to ensure safe operation of the home power grid.

Based on the experience of its work, the company "Skat Technology" concluded that with a significant increase in the load on the network (for example, the installation of the electric stove) should not be used by the old wiring. It will not help the right choice of the circuit breaker for the current current, since the wiring is not calculated on it. It is best to fully reconstruct or replace the network with the distribution of current consumers by groups.

Electrical engineering - accurate applied science, so the production of electrical goods is performed according to certain standards. This is clearly seen by the example of what circuit breakers are, the design of which is designed for specific operating conditions. The separation of consumers into groups has long been practiced in industrial networks. At the household level, this approach looks like this:

• for lighting reinforcement, the nominal machine must not exceed 10 A;
• for conventional outlets - 16 A;
• for power outlets for electric stoves, boilers and other, the selection of the circuit breaker for the power of consumers is carried out.

To implement this approach to the network, manufacturers are offered a sufficient selection of automata with different amounts of poles, differential type and other aggregates. For household purposes, apparatuses in cast cases should be used, in which all current-host parts are protected, which eliminates random lesion to the current. In order to install a universal version of the universal switch, switchgear (cabinets, assembly, etc.) are required.

The variety of electrical apparatus is also explained by the fact that their design provides for all sorts of installation conditions. In other words, the device with identical parameters may have several versions. therefore connecting circuit circuit It is a mandatory application to each product. It indicates the number of poles, phase connection points and neutrals, methods for preparing the wires to connect and other features of a particular model.

If a person has a minimal idea of \u200b\u200belectrical engineering, it will not be in a long time to reveal how to connect a single-phase circuit breaker on the shield of its apartment. Just look at the scheme in which there is nothing complicated. Single warning: If you change the machine, in no case put the larger power switch than the previous one. First you need to make sure that the wiring is able to withstand an increased load.

Care of electric equipment

Electro appliances, like any other devices, needs to be care. Maintenance of circuit breakers is carried out according to a certain procedure with strict frequency. Users often do not suspect such a need, but it is. Electrical engineering is subject to wear, gradually occurs the oxidation of contacts, aging isolation, wear of movable parts and other changes. Therefore, the calculation of the circuit breaker for power, made 5 years ago, may not correspond to the real state of affairs.

Probably, many of you have occurred situations when the flawlessly working network starts to flure. The obvious manifestation of this becomes a fact when an automatic switch is often triggered without visible reasons. The reason may be in the device itself, but most often this happens due to problems with wiring and hidden defects in electrical circuits of household appliances and equipment.

To identify and prevent such situations there is loading circuit breakers. It is carried out every three years using special equipment and is performed in order to verify the compliance of the actual state of the automaton with the requirements of the safe operation of the power grid. The automatic circuit breakers verification technique provides for testing the insulation status, the protection time of protection on ultralox and heating, the status of contacts and other parameters.

Conducting regular maintenance ensures troubleshooting in the early stages, warns more serious consequences and guarantees the safe operation of networks in the foreseeable future. The detected malfunctions of circuit breakers are eliminated as possible, but most often in such cases requires a complete replacement of electrical apparatus, especially in the case of their small sizes.

Manufacturers of electrical products make many spare parts for powerful industrial machines. For household or low-power equipment, only spare contact groups are usually produced. therefore replacing circuit breakers - Typical effect when repairing the power grid. Regular cargo care is a completely ground-based procedure, including money. Its main goal is prevention.

Among the technical characteristics of the automata, also indicates the guaranteed number of inclusion cycles / disconnection. For these indicators, circuit breakers have a service life measured by decades, subject to the competent installation of devices and timely care. They must fully comply with network parameters. In addition, to extend the timing of their service, do not use faulty electrical appliances that provoke the frequent disabling network.

Professional services from the company "Skat Technology"

Our company specializes in the work on engineering communications, including power grids. Our specialists are ready to make recommendations on the selection of circuit breakers and perform network design, including load calculations and distribution them, taking into account all safety rates. Experienced engineers will answer any practical issues, including how to connect the circuit breaker For different categories of current consumers, taking into account the installation conditions, the state of the wiring and other factors.

Our catalogs present a wide selection of electrical products from leading manufacturers. Our range will allow, without much difficulty, to fully complete the work on the arrangement of the power grid. If you confuse cost of circuit breakers With the logos of famous brands, we remind you that high-quality products cannot be frankly cheap. In addition, the service life of such electric equipment is much higher than that of products of dubious origin.

Those who wonder what circuit breakers are better, you should define what's the point you invest in it. For us, the defining factor is the reliability and safety in adequate costs? We offer electrical products at the highest prices, so we are convinced that our buyers do not overpay. Dimensions of circuit breakers Not always are the equivalent of prices, so if you want to obtain a normal result of the electrical output, use the services of the "Skat Technology" professionals.