This article continues a series of publications on electrical protection devices- circuit breakers, RCDs, automatic devices, in which we will analyze in detail the purpose, design and principle of their operation, as well as consider their main characteristics and analyze in detail the calculation and selection of electrical protection devices. This series of articles will be completed by a step-by-step algorithm, in which the complete algorithm for calculating and selecting circuit breakers and RCDs will be briefly, schematically and in a logical sequence discussed.
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Well, in this article we will figure out what a circuit breaker is, what it is intended for, how it works and how it works.
Circuit breaker (or usually just “machine”) is a contact switching device that is designed to turn on and off (i.e., for switching) an electrical circuit, protecting cables, wires and consumers ( electrical appliances) from overload currents and from currents short circuit.
Those. The circuit breaker performs three main functions:
1) circuit switching (allows you to turn on and off a specific section of the electrical circuit);
2) provides protection against overload currents, turning off the protected circuit when a current exceeding the permissible flows in it (for example, when connecting a powerful device or devices to the line);
3) disconnects the protected circuit from the supply network when large short-circuit currents occur in it.
Thus, automata simultaneously perform the functions protection and functions management.
According to design, three main types of circuit breakers are produced:
— air circuit breakers (used in industry in circuits with high currents of thousands of amperes);
— molded case circuit breakers (designed for a wide range of operating currents from 16 to 1000 Amperes);
— modular circuit breakers , the most familiar to us, to which we are accustomed. They are widely used in everyday life, in our houses and apartments.
They are called modular because their width is standardized and, depending on the number of poles, is a multiple of 17.5 mm; this issue will be discussed in more detail in a separate article.
You and I, on the pages of the site, will consider modular circuit breakers and residual current devices.
Design and principle of operation of a circuit breaker.
The thermal release does not operate immediately, but after some time, allowing the overload current to return to its normal value. If during this time the current does not decrease, the thermal release is activated, protecting the consumer circuit from overheating, insulation melting and possible wiring fire.
Overload can be caused by connecting powerful devices to the line that exceed the rated power of the protected circuit. For example, when a very powerful heater or electric stove with oven is connected to the line (with a power exceeding the rated power of the line), or several powerful consumers at the same time (electric stove, air conditioner, washing machine, boiler, electric kettle, etc.), or large quantity simultaneously switched on devices.
In case of short circuit the current in the circuit instantly increases, the magnetic field induced in the coil according to the law of electromagnetic induction moves the solenoid core, which activates the release mechanism and opens the power contacts of the circuit breaker (i.e., moving and fixed contacts). The line opens, allowing you to remove power from the emergency circuit and protect the machine itself, the electrical wiring and the closed electrical appliance from fire and destruction.
The electromagnetic release operates almost instantly (about 0.02 s), in contrast to the thermal one, but at significantly higher current values (from 3 or more rated current values), so the electrical wiring does not have time to heat up to the melting temperature of the insulation.
When the contacts of a circuit open and an electric current passes through it, an electric arc occurs, and the greater the current in the circuit, the more powerful the arc. An electric arc causes erosion and destruction of contacts. To protect the contacts of the circuit breaker from its destructive effect, the arc that occurs at the moment the contacts open is directed to arc chute (consisting of parallel plates), where it crushes, damps, cools and disappears. When the arc burns, gases are formed; they are vented out of the machine body through a special hole.
The machine is not recommended to be used as a regular circuit breaker, especially if it is turned off when a powerful load is connected (i.e., with high currents in the circuit), since this will accelerate the destruction and erosion of the contacts.
So let's recap:
— the circuit breaker allows you to switch the circuit (by moving the control lever up, the machine is connected to the circuit; by moving the lever down, the machine disconnects the supply line from the load circuit);
— has a built-in thermal release that protects the load line from overload currents, it is inertial and trips after a while;
— has a built-in electromagnetic release that protects the load line from high short-circuit currents and operates almost instantly;
— contains an arc-extinguishing chamber that protects power contacts from the destructive effects of an electromagnetic arc.
We have analyzed the design, purpose and principle of operation.
In the next article we will look at the main characteristics of a circuit breaker that you need to know when choosing one.
Look Design and principle of operation of the circuit breaker in video format:
Useful articles
For an electrician, switching equipment is one of the main devices with which he has to work. Circuit breakers have both a switching and protective role. Not a single modern electrical panel can do without automatic machines. In this article we will look at how a circuit breaker is designed and works.
Definition
A circuit breaker is a switching device designed to protect cables from critical current values. This is necessary in order to avoid damage to the current-carrying cores of wires and cables in the event of phase-to-phase faults and ground faults.
Important: The main purpose of a circuit breaker is to protect cable line from the consequences of short circuit currents.
The main characteristics of circuit breakers are:
Rated current (1, 2, 3, 4, 5, 6, 8, 10, 13, 16, 20, 25, 32, 35, 40, 50, 63, 80, 100, 125, 160, 250, 400, 630 , 1000, 1600, 2500, 4000, 6300);
Switching voltage;
Time current characteristic.
The machines are most widespread in household and industrial electrical networks with a voltage of 220/380 volts. Voltages are given for domestic electrical networks. Abroad they may differ. High voltage lines use relay circuits and current transformers. reflects after what period of time and at what value of current relative to the rated one the contacts will open. An example of it is shown in the figure below:
Operating principle
A circuit breaker (AB) is a switching device that contains two types of protection:
Electromagnetic release.
Thermal release.
Each of them performs the same job - opening power contacts, but under different conditions. Let's take a closer look at them.
When current flows through the machine below the rated value, its contacts will be closed indefinitely. But if the current is slightly exceeded, the thermal release, represented by a bimetallic plate, will open them.
The greater the current flowing through the contacts of the circuit breaker, the faster the bimetallic plate will heat up - this is described during the current characteristic and is indicated by the speed of the circuit breaker (the letter next to the rated current in the marking). Depending on how overloaded the circuit breaker is, the shutdown time depends on it; it can be tens of minutes, or it can be just a few seconds.
The electromagnetic release is triggered by a rapid increase in current. The magnitude of its operation current is orders of magnitude higher than the rated current.
This raises the question: “So why does the machine need two protections, if you can simply design it so that it turns off immediately when the rated current is exceeded?”
There are two answers to this question:
1. The presence of two protections increases the reliability of the system as a whole.
2. When connecting devices to the circuit breaker, the current of which changes during start-up and operation, so that false alarms do not occur. For example, in electric motors the starting current can be tens of times higher than the rated current, and during their operation short-term overloads on the shaft can occur (for example, lathe). Then, during a long start, the machine will also knock out.
Device
The circuit breaker consists of:
Housings (6 in the figure).
Terminals for connecting current-carrying conductors (2 in the figure).
Power contacts (in the figure - 3, 4).
Arc chamber (8 in the figure).
Levers connected to buttons or flags to turn it on and off (closing and opening contacts) (in the figure - 1 and what it is connected to).
Thermal disconnector (5 in the figure).
Electromagnetic disconnector (7 in the figure).
The number 9 indicates a latch for mounting on a DIN rail.
Power is connected to the terminals (usually the top, in practice it does not matter much), and the load is connected to the terminals on the opposite side. The current passes through the power contacts, the electromagnetic disconnector coil, and the thermal disconnector.
The electromagnetic protection is made in the form of a coil of copper wire, it is wound on a frame, inside of which there is a movable core. The coil contains from several units to a couple of dozen turns, depending on its rated current. Moreover, the lower the rated current, the more turns and the smaller the cross-section of the coil wire.
When current flows through the coil, a magnetic field is formed around it, which affects the movable core inside. As a result, it extends and pushes the lever, causing the power contacts to open. If you look at the figure, the lever is located below the coil, and when its core is lowered, the mechanism is activated.
Thermal protection is needed for long-term overcurrents. It is a bimetallic plate that bends to one side when heated. When a critical state is reached, it pushes the lever and the contacts are disconnected. The arc chute is needed to extinguish the arc that occurs due to the circuit opening under load.
The arcing process depends on the nature of the load and its magnitude. In this case, when an inductive load (electric motor) is disconnected, stronger arcs occur than when a resistive load is switched. The gases formed as a result of its combustion are discharged through a special channel. This significantly increases the service life of power contacts.
The arc chamber consists of a set of metal plates and dielectric covers. Conclusion Previously, circuit breakers were repaired, and it was possible to assemble one normally functioning one from several. It was possible to adjust and replace power contacts and other components.
Currently, machine guns are enclosed in a non-separable cast or rivet-assembled body. Repairing them is impractical, complicated and time-consuming. Therefore, the machines are simply replaced with new ones.
Content:
From the very beginning of the use of electrical circuits at the domestic and industrial level, the problem of protecting lines from current overloads arose. This is necessary to preserve the devices, household appliances, all elements in the circuit from destruction in the event of a short circuit, including the wires themselves. At currents exceeding design section wires, insulation and conductive metal structure melt, to avoid this, the circuit must be immediately disconnected from the power source. You cannot assign an electrician on duty to each section of the circuit; shutdowns must occur automatically. Many methods have been invented: thermal relays, bimetallic plates, fuses and others. The latest devices that are now effectively used in electrical networks are circuit breakers.
General concepts and scope
Structurally, this is a conventional switching device, a switch whose position can be set manually (on or off). But this device provides automatic shutdown when the rated current passing through the contacts is exceeded. An increased current can occur when connecting electrical appliances that consume high power, or a short circuit in the circuit of faulty electrical consumers.
In industrial, residential, administrative buildings and other structures, automatic machines are installed in distribution boards. But manufacturers of household appliances and various electrical equipment also include circuit breakers in their products, this is additional protection. There is a misconception that circuit breakers protect service personnel from electric shock. To do this, an RCD (touch protection device) is installed in the circuit, the design and operating principles of which require a separate, more detailed consideration. Conventional circuit breakers perform the following functions:
- switching, connection and shutdown in manual mode;
- automatic circuit shutdown at currents exceeding the set value;
- almost instantaneous shutdown at very high short-circuit currents.
It turns out that these devices perform control and protection options for the electrical network, main task- prevent overheating of the wires and melting of the insulation, followed by a short circuit. As a result of excessive current overloads, a fire may occur with all the ensuing consequences.
Types of circuit breakers
All circuit breakers can be divided according to their design and the amount of current passed:
- Air circuit breakers are capable of passing currents of thousands of amperes in operating mode, therefore they are used in industrial facilities that consume high electrical power.
- Automatic machines in a molded case have a wide range of operating current from 16 to 1000 A, so they are universal and widely used in household and industrial facilities.
- Modular circuit breakers - such products are most in demand at the household level and are used for protection electrical circuits in apartments, private houses and other commercial facilities where electricity is used.
Manufacturers make products of the same size with standard rail mounts, but different in operating current ratings: 1, 2, 3, 6, 10, 16, 20, 25, 32, 40 A and more.
In addition to different operating current values, circuit breakers differ in the number of poles connected to them:
- Single-pole circuit breakers protect the section of the circuit from the distribution board to the electricity consumer (to the socket or light bulb). A single-phase circuit breaker increases operational reliability, but does not guarantee complete protection of the circuit from the phase from the distribution board through the load to the zero bus in the distribution board.
To increase the reliability of protecting a section of a circuit, circuit breakers must be installed on both poles (on the phase and neutral wires in the distribution board).
- A two-pole circuit breaker completely disconnects a single-phase circuit (the phase and neutral wires are broken).
Such machines are used in networks where high-power heating appliances, cookers, air conditioners and split systems are connected. Used in three-phase networks, where devices are designed for a voltage of 380 V;
- A three-pole electrical circuit breaker is installed in a three-phase network of a four-wire cable. When operating electrical appliances connected according to a star or delta circuit (electric motors), the phases pass through the circuit breaker, and the neutral wire bypasses it. If the set current value or temperature in one of the phases is exceeded, all three are switched off.
- A four-pole electric circuit breaker is most often used as an input circuit breaker to protect the network to which a high-power electric motor is connected in a star configuration.
In the event of an accident in one of the phases, the network is completely de-energized; circuit breakers disconnect all four wires from the power source.
Main technical characteristics
Regardless of the brand of circuit breaker, the following are important for everyone: electrical parameters:
- maximum permissible and operating voltage;
- maximum permissible operating current;
- permissible power;
- the magnitude of the tripping current of the release;
- tripping time of the release when the threshold current value is exceeded;
- maximum permissible temperature of conductors;
- the response time of the circuit breaker when the threshold temperature on the bimetallic plate is reached and many other parameters that are important when choosing a circuit breaker.
Professionals know the basics well technical specifications circuit breakers of various models, they have no questions about how to choose circuit breakers. For consumers at the household level, in order not to go into complex graphs and physical formulas, it is enough to know the values listed above and the following classification:
B – a circuit breaker of this category trips when the rated current value is 3–5 times higher. They are effective when used on sites with old wiring;
WITH - electric machines this category is triggered when the operating current load is 5–10 times higher, they can be used in new buildings where new wiring with copper wires is installed;
D – automatic switch with a minimum time interval of operation when the threshold temperature and current are exceeded. Shutdown occurs instantly, which reliably protects the electric motor windings from burnout.
Design, main elements and principle of operation
All types of machines considered have different sizes, design features, technical characteristics, but the principle of operation and basic elements are the same. Therefore, let’s look at how a panel single-pole electric circuit breaker works.
The higher the current, the higher the temperature, the more the plate bends, affecting the contact opening mechanism.
The main characteristics of circuit breakers are indicated by manufacturers on the housing.
If it is difficult for you to navigate when choosing circuit breakers, in the terminology of technical characteristics, consult the seller or ask a competent specialist to help you choose the right circuit breaker.
Every repair and installation technician knows that electric current is a source of increased danger, so he pays attention to this during the design and installation of lines. special attention. Among other devices that are designed to ensure the normal and correct operation of highways and devices in normal mode, the circuit breaker, which performs many safety functions, has gained great popularity. This article discusses the classes of circuit breaker, what it is needed for, the principle of operation and scope of application, as well as the algorithm for connecting the device.
Types of switches
A circuit breaker is a current-carrying unit that is mounted on power lines and other highways, as well as in consuming devices to disconnect and block operation during short circuits, overloads and other emergency situations. These devices belong to switching technology and, due to their technical characteristics, cope well with the assigned tasks, therefore they are often used on high and medium voltage power lines.
There are several types of switches, which can be divided according to operating conditions into the following types:
- Low-voltage circuit breaker - used on highways and power plants with voltages up to 1000 Volts. Most often these are household lines that are used in residential premises or in small production;
- High voltage units. The main difference between such products is their ability to conduct large currents with minimal resistance and losses, moreover, their response rate is much higher: where a conventional machine turns off the power already at a minimum overload, a high-voltage device will continue to operate until the operating limit occurs.
This is a general classification of circuit breaker; each of these points has its own devices that differ from each other in many respects. Depending on their design and configuration, protection units come in three types.
First of all, this is a type that includes modular structures. In this case, the automation is made in the form of a product in a plastic case, with a special fastening unit on the rear wall, thanks to which it can be installed on a metal rail inside electrical panel. Such a device includes a copper coil that responds to overloads or increased temperature in the network, a control lever, a spark-extinguishing element and terminals for connecting the conductor.
Due to the reliability and simplicity of the device, the modular unit can be operated in any conditions, including at low temperatures. In case of emergency situation a thermal or current cutoff occurs in the machine, which turns off the electricity on the output conductor. It turns out that there is current at the inlet, but there is no current at the outlet, until the control lever is returned to the upper position.
The second version is an automatic machine in a cast case. In this case, the units are capable of conducting a current that is several times higher than in modular designs; in some devices it can reach 3.2 kiloamperes. Most often, such units are used at industrial facilities, when there is a need to transmit current from high voltage. A conventional machine in such conditions will operate under constant load, which will lead to constant operation or overheating of the device. Such equipment has a three- or four-pole housing design, depending on the task being solved.
The third type of safety power units are air circuit breakers. This type of units is intended for installation on high-voltage lines, current transformers or heavy-duty electric motors. The technical range of operation of such machines reaches up to 6300 amperes, so they are often used on highways with very high voltages. The operating principle of such a circuit breaker is to ensure a double network break at the input and output of the machine. For this purpose, the unit is equipped with arc-extinguishing chambers and grilles on both sides. The design of the device includes a switching coil, a closing spring, a drive for charging it, as well as automation for controlling the entire part.
Release
This part is available in every machine; it is responsible for mechanically disconnecting the input conductor from the cable carrying voltage to the consumer. Depending on the operating principle, the release can be mechanical, thermal or magnetic. In a mechanical part, all actions are carried out automatically, depending on the height of the voltage and the expansion force of the plate and springs. The thermal unit is triggered when the temperature at the ends of the cable rises and turns off the power. The last type of release is equipped with an electromagnet, which, when the voltage rises to a certain height, is activated and opens the contact.
Ultra-high load devices
Automation designed to operate on a high-voltage line has a complex design and slightly different response algorithms in an emergency. Such products belong to professional equipment, therefore their installation should be carried out only by qualified personnel who have a license to work and have been trained in safety rules for power installations in accordance with technical supervision standards. Such machines are subject to increased requirements for safety, response speed, level of protection, ease of maintenance and quiet operation.
The load that occurs on the conductor during a power outage is accompanied by the formation of a large arc, which, if not extinguished, can cause a fire. Therefore, the composition protective device includes special elements that act as a buffer to absorb current discharge. Also, the design of a circuit breaker designed to operate at high voltage includes the following parts:
- Contact system, most often isolated from the main body by ceramic or glass spacers;
- Live parts or conductors;
- Insulated housing. If it is metal, then it is located at some distance from the main structure and must have a grounding rod;
- Drive mechanism. Unlike a conventional low-voltage circuit breaker, in this case the control lever is located on the outer casing, and when it is lowered down, the contacts of the device in the panel turn off the power to the input conductor. Many modern units are equipped with servo drives with remote control, which are activated from the operator's console.
Thus, we can conclude that the machine, designed to operate under increased load, has a more complex device and several levels of protection against network overloads; its use can ensure the operation of several distribution stations or step-down transformers at once.
All of the above units refer to devices intended for operation on highways with alternating current. This is a type of voltage that, when transported through conductors, has a low resistance and absorption coefficient, but many household and industrial appliances require constant electricity to operate. To convert the first type of current into direct current, a transformer and an inverter are needed, which are installed in power distribution units and equipped with circuit breakers for medium voltage up to 1000 Volts.
Why do you need a machine gun?
The main direction in which these units are used is to ensure safety in electrical installations and prevent fire from short circuits. Based on the execution of the specified function, the machine must operate during an increase in current or overload on the conductors, for example, in the winding of an electric motor. Such a device is designed for high performance and, in case of insufficient voltage, does not interrupt the network by opening the contacts.
There is also a separate category of products, the type of operation of which is based on the reaction of the coil and plate to ultra-low electricity. Therefore, this type of device is also called dual-range, since the part can turn off the power both when the voltage is too high and when it is too low. Most often, such an automatic machine is used on lines to which motors sensitive to current drops are connected, so that at the moment of sagging, the winding on the coils does not overheat and the drive does not fail.
A separate classification can be made of the type of devices that are used to work on DC. They have a device and design similar to the machines mentioned above, as well as the operation process. Such units are divided into devices operating in mains up to 1000 Volts and above this standard.
On electrical lines with a rating of 1000 Volts or more, hybrid installations are most often used, which include many elements with several levels of short circuit protection that duplicate each other. In most cases, these are large industrial facilities in the field of metallurgy, engines of electric trains and trolleybuses. Such a switch includes two parallel lines:
- SF6 branch;
- Vacuum element.
Thanks to the latest developments of scientists and designers, the operating speed of such a machine is calculated in fractions of seconds. Voltage is connected to the input contact of the vacuum device, and voltage is removed from the output contact of the SF6 gas device; control is carried out via a fiber optic cable by a specially designed automated processor.
Installation process
Any installation must be carried out in accordance with the project, which is developed on the basis of terms of reference and technical characteristics of the future line.
Important! If you do not have sufficient experience and knowledge in this area, as well as special tools with dielectric handles, it is not recommended to try to install any type of circuit breaker yourself, as this can lead to injury and disfigurement.
Installation or replacement of a used machine is carried out according to the following algorithm of actions:
- Power off the entire line. If the input circuit breaker is changed, then you need to de-energize the entire line to the nearest transformer. The worker must wear rubber gloves and other personal protective equipment;
- The absence of voltage is checked, this can be done using a multimeter or indicator;
- The fixing bolt on the terminals at the top and bottom is unscrewed, then the wires are removed from the release seat and taken to the side;
- On the lower plane of the machine there is a special plate, which is equipped with a spring. To remove the machine, you need to press it away from the body with a flat screwdriver and remove the unit from the rack;
- A new machine is installed on the seat, its connection is carried out in reverse order. If this is a multi-profile switch, then the wires must be fixed in order from the current-carrying cable to the consuming one.
Most often, the installation of the machine is carried out in a metal or plastic shield, which is attached to the outer or interior wall buildings by hidden or external planting.
Thus, we can conclude that to ensure the safe operation of electrical installations, household or industrial appliances, a circuit breaker is required, since in the event of an emergency it will be able to independently turn off the power to all rooms and units.
Video
To protect household electrical circuits, modular circuit breakers are usually used. Compactness, ease of installation and replacement, if necessary, explains their wide distribution.
Externally, such a machine is a body made of heat-resistant plastic. On the front surface there is an on/off handle, on the back there is a latch for mounting on a DIN rail, and on the top and bottom there are screw terminals. In this article we will look at.
How does a circuit breaker work?
In normal operation mode, a current flows through the machine that is less than or equal to the rated value. Supply voltage from external network supplied to the upper terminal connected to the fixed contact. From the fixed contact, current flows to the movable contact closed with it, and from it, through a flexible copper conductor, to the solenoid coil. After the solenoid, the current is supplied to the thermal release and after it to the lower terminal, with the load network connected to it.
In emergency modes, the circuit breaker disconnects the protected circuit by triggering a free tripping mechanism driven by a thermal or electromagnetic release. The reason for this operation is an overload or a short circuit.
Thermal release is a bimetallic plate consisting of two layers of alloys with different coefficients of thermal expansion. When passing electric current the plate heats up and bends towards the layer with a lower coefficient of thermal expansion. When the specified current value is exceeded, the bending of the plate reaches a value sufficient to activate the release mechanism, and the circuit opens, cutting off the protected load.
Electromagnetic release consists of a solenoid with a movable steel core held by a spring. When the specified current value is exceeded, according to the law of electromagnetic induction, an electromagnetic field is induced in the coil, under the influence of which the core is drawn into the solenoid coil, overcoming the resistance of the spring, and triggers the release mechanism. In normal operation, a magnetic field is also induced in the coil, but its strength is not enough to overcome the resistance of the spring and retract the core.
How does the machine work in overload mode?
An overload mode occurs when the current in the circuit connected to the circuit breaker exceeds the rated value for which the circuit breaker is designed. In this case, the increased current passing through the thermal release causes an increase in the temperature of the bimetallic plate and, accordingly, an increase in its bending until the release mechanism is activated. The machine turns off and opens the circuit.
The thermal protection does not operate instantly, since it will take some time for the bimetallic strip to warm up. This time can vary depending on the magnitude of the excess current from a few seconds to an hour.
This delay allows you to avoid power outages during random and short-term increases in current in the circuit (for example, when turning on electric motors that have high starting currents).
The minimum current value at which the thermal release must operate is set using an adjusting screw at the manufacturer. Typically this value is 1.13-1.45 times higher than the denomination indicated on the machine label.
The magnitude of the current at which thermal protection will operate is also affected by temperature. environment. In a hot room, the bimetallic strip will warm up and bend until it triggers at a lower current. And in rooms with low temperatures, the current at which the thermal release will operate may be higher than permissible.
The reason for network overload is the connection to it of consumers whose total power exceeds the calculated power of the protected network. Simultaneous activation of various types of powerful household appliances (air conditioner, electric stove, washing and dishwasher, iron, electric kettle, etc.) - may well lead to the operation of the thermal release.
In this case, decide which consumers can be disabled. And don’t rush to turn on the machine again. You still won't be able to cock it in working position until it cools down and the bimetallic plate of the release returns to its original state. Now you know during overloads
How does a machine work in short circuit mode?
In case of a short circuit it is different. During a short circuit, the current in the circuit increases sharply and many times to values that can melt the wiring, or rather the insulation of the electrical wiring. In order to prevent such a development of events, it is necessary to immediately break the chain. This is exactly how an electromagnetic release works.
The electromagnetic release is a solenoid coil containing a steel core held in a fixed position by a spring.
A multiple increase in current in the solenoid winding, which occurs during a short circuit in the circuit, leads to a proportional increase magnetic flux, under the action of which the core is drawn into the solenoid coil, overcoming the resistance of the spring, and presses the release bar of the release mechanism. The power contacts of the machine open, interrupting the power supply to the emergency section of the circuit.
Thus, the operation of the electromagnetic release protects the electrical wiring, the closed electrical appliance and the machine itself from fire and destruction. Its response time is about 0.02 seconds, and the electrical wiring does not have time to heat up to dangerous temperatures.
At the moment the power contacts of the machine open, when a large current passes through them, an electric arc appears between them, the temperature of which can reach 3000 degrees.
To protect the contacts and other parts of the machine from the destructive effects of this arc, an arc-extinguishing chamber is provided in the design of the machine. The arc chamber is a grid of a set of metal plates that are insulated from each other.
The arc occurs at the point where the contact opens, and then one end of it moves along with the movable contact, and the second slides first along the fixed contact, and then along the conductor connected to it, leading to the rear wall of the arc-extinguishing chamber.
There it divides (splits) on the plates of the arc-extinguishing chamber, weakens and goes out. At the bottom of the machine there are special openings for the removal of gases formed during arc combustion.
If the machine turns off when the electromagnetic release is triggered, you will not be able to use electricity until you find and eliminate the cause of the short circuit. Most likely the cause is a malfunction of one of the consumers.
Disconnect all consumers and try to turn on the machine. If you succeed and the machine does not kick out, it means that one of the consumers is indeed to blame and you just have to find out which one. If the machine breaks down again even with the consumers disconnected, then everything is much more complicated, and we are dealing with a breakdown of the wiring insulation. We'll have to look for where this happened.
This is how it is in various emergency situations.
If tripping your circuit breaker has become a constant problem for you, do not try to solve it by installing a circuit breaker with a higher rated current.
The machines are installed taking into account the cross-section of your wiring, and, therefore, more current in your network is simply not allowed. You can find a solution to the problem only after a complete inspection of your home’s electrical supply system by professionals.