Any electrical equipment is created to work with a certain electrical energy, depending on the current and voltage in the network. When their value becomes larger than the designed norm, an emergency mode occurs. To prevent the possibility of its formation or to eliminate the destruction of electrical equipment, protection is called upon. They are created under the specific conditions of an accident.

The insulation of the household electrical network is calculated on the limit value of the voltage slightly above one and a half kilovolts. If it grows more, then a spark discharge begins to penetrate through the dielectric layer, which can develop into an arc that forms a fire. To prevent its development, they create protections that work according to one of two principles: disconnecting the electrical circuit of a house or apartment from high voltage, removing dangerous potential overvoltage ...

Often in everyday life, a situation arises when the voltage in the network is unstable, or, as they say in common parlance, the light blinks. This phenomenon not only causes discomfort, but can also lead to failure of household electrical appliances, especially those that are sensitive to voltage surges. Therefore, it is very important in a short time to find the cause of this negative phenomenon and eliminate it. In this article, we will try to understand why the light blinks, and we will present the appropriate solutions to this problem.

One of the most common reasons that a light may blink is poor power supply. In this case, we are talking about an unstable voltage, the value of which changes stepwise. But also do not forget that the reason why the light may blink can also be a malfunction of a lamp or other household appliance that worked in an uncharacteristic ...

In the life of every person at one or another stage of life, the question arises of choosing a profession. This article is dedicated to those who have chosen the profession of electrician from many different areas of activity. How to become an electrician? We will try to answer this question by considering all aspects of this profession.

Many people have shown interest in this profession since their school years. Someone followed in the footsteps of relatives, but someone just likes everything related to electricity - there are many options. You can master this area of ​​activity, like any profession, always. Not all electricians became such from the very beginning, for many people, the profession of an electrician can be second, third, etc. in life, as the case may be. But in any case, an electrician is not just a person who has received an education, it is a person whose soul lies in this profession, for whom to be an electrician is not just work ...

What determines the long-term permissible cable current? To answer this question, we will have to consider transient thermal processes that occur under conditions when an electric current flows through the conductor. Heating and cooling a conductor, its temperature, connection with resistance and cross-section - all this will be the subject of this article.

The figure shows the graphs of the current and temperature in the conductor over time. From time t1 to time t3, current I passed through the conductor. Here you can see how, after turning on the current, the temperature of the conductor gradually rises, and at time t2 it ceases to increase, stabilizes.But after turning off the current at time t3, the temperature begins to gradually decrease, and at time t4 it again becomes equal to the initial value (T0). So, we can write the heat balance equation for the conductor heating process ...

When connecting a private house or apartment to electric networks, there is no question of whether to make sealing of the meter or not - this is a mandatory procedure, without which it is impossible to connect to electric networks. Therefore, if you need the first connection or connection after the suspension of power supply services (for example, due to violation of the terms of the contract), the question arises of the need to seal the meter. What is a filling, and for what purpose is it performed?

Sealing an electric meter is the installation of a special seal on an electric meter, which prevents opening the case and, accordingly, undesirable manipulations of the meter and other elements of the metering board from the point of view of supplying the organization. The seal is installed exclusively on a working, verified metering device ...

The traditional way to get rid of excess energy released in frequency converters during braking of asynchronous motors controlled by them was to dissipate it in the form of heat on resistors. Braking resistors were used wherever there was a high inertia of the load, for example, in centrifuges, on electric vehicles, on load stands, etc.

Such a solution was necessary in order to limit the maximum voltage at the terminals of the converters in braking mode. Otherwise, the frequency converters would fail, because it would be impossible to control the parameters of acceleration and braking. Braking resistors did not burden the equipment economically, but some inconveniences invariably entailed. Resistors are dimensional, they are very hot, they need protection against moisture and dust. And all this is connected only with what needs to be dispelled ...

Thunderstorm discharge is very dangerous, since its value can reach several hundred thousand volts. After each thunderstorm, the equipment fails, the power lines are damaged, and people can also be injured. It is impossible to determine where the lightning strikes, so it is a mistake to assume that this phenomenon will bypass your home. Lightning may never get into a particular section of the power grid and, accordingly, the danger of a thunderstorm can be underestimated. If lightning for several years has never hit a particular section of the power grid, this does not mean that such a possibility is excluded.

The occurrence of lightning overvoltage in the household electrical network in the absence of appropriate protection will lead to the failure of household electrical appliances that were included in the network at that time, and there is also a danger that residents of the house will suffer. Therefore, care must be taken to protect the wiring ...

For a long time you will not surprise anyone with a welding inverter. And there is nothing unusual in this, because it is much more convenient for any welder to operate with a compact and mobile device than with a heavy iron transformer. The subject of this article, however, will be precisely the modern welding inverters.

We will try to evaluate many advantages and some of the few disadvantages of welding inverters, consider their various options, and in the end we will compare the advantages and disadvantages so that even someone who is just thinking about purchasing a welding inverter can confidently come to a decision on its purchase.What is a welding inverter today? First of all, it is a compact semiconductor welding machine equipped with all types of shields and equipped with many options that facilitate the work of the welder, even if he is new to the profession ...

In bathrooms and other rooms with high humidity, lighting plays an important role in the interior, because it is thanks to it that the design is unique, since it is the light that emphasizes all its details. But when designing lighting systems in wet rooms, in addition to beauty, safety is also taken into account, because water procedures should not be accompanied by anxiety. For this reason, the fixtures here must be special, waterproof.

Today, in every store that sells lighting products, you can easily choose a moisture-resistant lamp. Such a lamp will come out somewhat more expensive than usual, however, you need to pay for safety anyway. But in return you will get confidence in the safety in your bathroom , and even if the family has small children, then you don’t have to worry...

A broken ground wire in a three-phase electrical network is a dangerous phenomenon that can lead to various negative consequences for household electrical appliances, as well as for people who operate them. In this article, we will consider the consequences of a zero wire break with a specific example and the corresponding methods of protecting home wiring from a zero break.

As an example, consider an apartment building, powered by the most common TN-C-S grounding system. A system of this type provides grounding of the neutral of a power source - a substation transformer. From the substation to the consumer, in this case, the house, electricity is supplied through four conductors - three phase conductors and a conductor, which combines the functions of a working neutral and protective grounding conductor. After entering the building, the combined conductor is divided ...

Owners of individual houses and cottages are increasingly beginning to understand that the use of electricity not only greatly facilitates the fulfillment of everyday household needs, but also poses certain risks to humans. In life, there is always the possibility of an emergency, which can lead to electrical injury.

The electrical safety of an individual building requires constant close attention from the owner. One of the issues of its maintenance is the operation of an individual ground loop, which must not only be created according to a certain methodology, but also correctly selected design, having performed a reliable calculation of all its elements. We’ll make a reservation right away that anyone who is familiar with the basics of electrical engineering can do it yourself. To do this, below is the methodology for its implementation. It is for guidance only ...

Back in 1836, the English physicist and inventor Michael Faraday created a special device for shielding equipment from electromagnetic radiation. This device is relevant to this day, and, as before, bears the name of a scientist. It's about the Faraday cage. This device is a protective cage made of highly conductive metal, and, as a rule, grounded. The principle of operation of this simple device is also quite simple.

When an external electric field acts on the cell, the free electrons of the metal of the cell come into motion, and the opposite sides of the structure are charged so that their field compensates for the external electric field. This can be verified by a simple experiment with two electroscopes and a Faraday cage charged from a high voltage source ...