For starting, reversing, forcibly stopping countercurrent asynchronous electric motors, electricians use contactors and magnetic starters. The reliability of the system as a whole, as well as the electrical safety of the service personnel, depend on the correct choice of switching equipment.

Choosing a starter and excess switching current leads to large financial costs, when it is switched, flip flops of a higher volume are heard than those produced by small starters. Inadequate switching power starters will not last for a long time, they will warm up, and burn terminal blocks and contacts. As a result, the transition resistance of the contact will increase until the contact disappears completely, which will lead to premature replacement of the device. Circuit breakers must also be correctly selected, especially when starting the engine hard ...

It happens that when you turn on a particular electrical appliance in an apartment, such as a multicooker or a lighting system with energy-saving lamps, or the power supply of a particular electrical appliance, the circuit breaker starts to buzz in the electrical panel. And usually this phenomenon is not associated either with the increased power of the connected consumer, or with the corresponding current approaching the rating of the machine. And it is connected with a certain power or with a certain household appliance.

In some cases, the hum completely disappears with an increase in load power, and often the landlord has no complaints about the smell of burning ... So, there is no arc buzzing inside the machine. And then what? Where does this hum come from? Is he dangerous? How to deal with this phenomenon and is it worth it to fight with it at all? Let's think about it. Everyone who is familiar with the circuit breaker device knows that two protective tripping mechanisms are simultaneously implemented inside it: thermal and electromagnetic ...

Household consumers are gradually phasing out incandescent lamps, and they are using them less and less. At first they were replaced by compact fluorescent lamps (CFLs). They consume 5 times less energy at the same brightness. That is, a 20 W fluorescent lamp can replace a 100 W incandescent lamp. For this they were called energy-saving.

Technology does not stand still and in the last 5 years, LED lamps or LEDs have strengthened in the market. The range of products is wide enough from light panels and tapes to searchlights and lamps for all possible socles. At the same time they shine 10 times brighter than incandescent lamps of the same power. Let's take a closer look at the differences between energy-saving and LED lamps. LED lamps actually also belong to energy-saving ones, but in the people this name is fixed to compact fluorescent lamps, although they save energy not like LED ones ...

The relay has a limited resource, this is primarily due to the principle of its operation: the electromechanical relay operates due to the magnetic field and the closure of mechanical contacts. Mechanical contacts wear out, the coil burns out, hence the need for repair. Most often, the repair consists in cleaning the contacts or solving problems with the coil.

Before moving on to repair issues, let's walk through the components of an electromagnetic relay. The relay itself compares the magnitude of the control action, after which the signal is transmitted to the controlled circuit. In our case, an electric current is supplied to the coil.The anchor is attracted to the core of the coil due to the magnetic force created by the magnetic flux. The relay is triggered if sufficient voltage and current are supplied. When the electromagnet trips, the contacts close ...

The transistor appeared in 1948 (1947), thanks to the work of three engineers and Shockley, Bradstein, Bardin. In those days, their rapid development and popularization were not yet anticipated. In the Soviet Union in 1949, the prototype of the transistor was presented to the scientific world by the Krasilov laboratory, it was a C1-C4 triode (germanium). The term transistor appeared later, in the 50s or 60s.

However, they found widespread use in the late 60s, early 70s, when portable radios came into fashion. By the way, they have long been called the "transistor". This name stuck due to the fact that they replaced electronic tubes with semiconductor elements, which caused a revolution in radio engineering. Transistors are made of semiconductor materials, for example, silicon, germanium was previously popular, but now it is rarely found, due to its high cost and worse parameters, in terms of temperature and other things ...

One of the reasons for this unpleasant phenomenon is explained very simply. Our body is very interesting in matters of electrical safety: on the one hand, with our sensory organs we can’t recognize the presence of a nearby potential of electrical voltage and, at the same time, when we get under its action, we get unpleasant sensations, injuries, and tragic injuries. In such situations, it is customary to say that we are shocked.

Let's try to open this question in more detail, from the point of view of electrical engineering. We will need to take into account the nature of the current flow, the properties of our body, the experience of accidents accumulated by our predecessors, formulated by safety rules. An electric current is an ordered (oriented in a certain way) motion of the smallest particles with charges. It is created under the influence of the applied external forces of the electric field ...

Modern man is used to the fact that electricity constantly serves to satisfy his needs and does a great, useful job. Quite often, the assembly of electrical circuits, the connection of electrical appliances, the electrical installation inside a private house is performed not only by trained electricians, but also by home craftsmen or hired migrant workers.

However, everyone knows that electricity is dangerous, can injure and therefore requires the quality of all technological operations to ensure reliable passage of currents in the working circuit and ensure their high isolation from the environment. The question immediately arises: how to check this reliability after the work seems to be done, and the inner voice is tormented by doubts about its quality? The answer to it allows you to give a method of electrical measurements and analysis, based on the creation of increased loadcalled phase-zero loop resistance measurement...

Since the 19th century, people have been using electricity, paying money for it. During this time, many methods of calculation between electricity supplying organizations and consumers have been tested, but, time has shown that the best option is to automatically record the work performed by the devices with their subsequent payment on the fact. To this end, manufacturers of electrical equipment produce electric meters that take into account the energy consumed by the consumer in various ways.

Nowadays, two of their types are widespread: induction devices of old models, operating on the basis of an electromechanical design, static products using electronic components and microprocessor technology. Both types of these devices work according to one general principle: they constantly consider the power passing through them and display this information on a counting mechanism or display...

Switching is turning the appliance on or off in the network. To do this, use disconnectors, switches, circuit breakers, relays, contactors, starters. The last three (relays, contactor and magnetic starter) are similar in structure, but are designed for different load capacities. These are electromechanical switching devices.

To turn on the load, you need to apply voltage to its conclusions, it can be constant and variable, with a different number of phases and poles. The voltage can be applied in several ways: a detachable connection, a disconnector, through a relay, a contactor, a starter or a semiconductor switching device. The first two methods are limited both by the maximum switching power and by the location of the connection point. This is convenient if you turn on the light or the device with a switch or an automatic machine ...

A rectifier is used in an AC circuit to convert it to DC. The most common is a rectifier assembled from semiconductor diodes. At the same time, it can be assembled from discrete (separate) diodes, or it can be in one housing (diode assembly).

Let's look at what a rectifier is, what they are, and at the end of the article we will conduct simulation in a Multisim environment. Modeling helps to consolidate the theory in practice, without assembly and real components, view the forms of voltages and currents in the circuit. For single-phase voltage, there are three common rectification schemes.The simplest circuit consists of only one diode, which gives a constant unstabilized ripple voltage at the output. Diodes are connected to the power circuit by a phase wire, or by one of the terminals of the transformer winding, the second end to the load, the second pole of the load ...

Drilling walls and ceilings is a common thing for an electrician, installer, repairman. Yes, and a simple layman may occasionally need to drill a hole in the wall or in the ceiling. And if there is a drill or a puncher at home, then you can do everything yourself, only by answering a question about how to avoid getting into hidden wiring.

If you get into the wiring with a drill or a drill, then in the most optimistic case you will break the cable and your sockets will stop working. With less success - there will be a short circuit through the tool, the circuit breaker will open at the entrance to the apartment, but the wiring will again have to be repaired. In the worst case, an electric shock or even a fire awaits a person. Therefore, when drilling, it is better not to get into the wiring. About how not to get into the wiring and will be discussed in our article. Suppose you decide to install a Swedish wall for a child, and fixing to the wall is necessary ...

The Sonoff World On relay, from the family of devices for wirelessly controlling the inclusion and disconnection of household loads via Wi-Fi from the network, will become a rather useful and convenient element of your home automation system. If you use a smartphone, you have Wi-Fi at home, and you also want to control the power of various network loads directly from your smartphone, even if you are away from home, then these Wi-Fi relays are just for you.

Just install the Sonoff relay near the outlet or switch (or even instead of the outlet or instead of the switch), and connect your household appliance in series through it with a 220 volt network. Then create a connection via the Internet, configure communication with the relay via Wi-Fi, and control your household electrical appliances directly through the application from your smartphone. Let's take a closer look at the five Sonoff World On relay models. Relaydesigned to control the power of any electrical appliance ...