Various electrical equipment and modern electrical networks as a whole use primarily AC for their work. Alternating current feeds engines, induction furnaces, machine tools, computers, heaters, electric heaters, lighting devices, household appliances.

It is impossible to overestimate the importance of alternating current for the modern world. However, high voltage is used to transmit electrical energy over long distances. And the technique requires low voltage for its power supply - 110, 220 or 380 volts. Therefore, after transmitting to a distance, the voltage must be reduced. Lowering is carried out in steps using transformers and autotransformers. In general, transformers are up and down. Step-up transformers are installed in generating power plants, where they increase received from the generator ...

The function of any electric generator is to generate an electric current. But in fact, the generator does not produce anything, but only converts one form of energy into another (as is characteristic of all energy processes in nature). Most often, pronouncing the phrase “electric generator”, they mean a machine that converts mechanical energy into electrical energy.

Mechanical energy can be obtained from gas or steam expanding under pressure, from falling water, or even manually. In any case, in order to receive electric energy from a generator, it must first transfer this energy in an acceptable form, most often in mechanical form. Generators operating by mechanical drive are the dominant form of generators in the modern world. Such generators operate in nuclear and hydroelectric power plants, in automobiles, in diesel and gasoline generators ...

When we pronounce the phrase “electric current”, we usually mean the most diverse manifestations of electricity. The current flows through the wires of high-voltage power lines, the current rotates the starter and charges the battery in our car, lightning during a thunderstorm is also an electric current.

Electrolysis, electric welding, sparks of static electricity on a comb, current flows in a spiral of an incandescent lamp, and even in a tiny pocket flashlight a tiny current flows through an LED. Needless to say, our heart, which also generates a small electric current, is especially noticeable during the passage of the ECG procedure. In physics, it is customary to refer to the ordered movement of charged particles and, in principle, any carriers of electric charge as electric current. An electron moving around an atomic nucleus is also a current. And a charged ebony wand, if you hold it in your hand ...

During magnetization reversal of magnetic materials by an alternating magnetic field, part of the energy of the magnetic field involved in the magnetization reversal is lost. A specific part of the power, which is called “specific magnetic loss”, is dissipated per unit mass of a certain magnetic material in the form of heat.

Specific magnetic losses include dynamic losses as well as hysteresis losses. Dynamic losses include losses caused by eddy currents and magnetic viscosity. Losses due to magnetic hysteresis are explained by irreversible movements of domain boundaries. Each magnetic material has its own hysteresis loss proportional to the frequency of the magnetizing magnetizing field, as well as the area of ​​the hysteresis loop of this material. To reduce hysteresis losses, most often resort to the use of ...

The modern electrochemical industry boasts a wide variety of electrical insulating materials. Glass fiber materials, which include synthetic resins, deserve special attention, since these materials are not only highly electric, but also have significant mechanical strength, as well as heat and moisture resistance.

Natural electrical insulating materials, such as mica and asbestos, artificial counterparts - electric cardboard and cotton tapes - share the market for modern electrical insulation with high-quality fiberglass, which is part of fiberglass fabrics, fiberglass, fiberglass and fiberglass. In addition, synthetic films are widely used: melinex, lavsan and others. It is thanks to the appearance of synthetics in the composition of electrical insulation materials, power and durability of modern equipment...

In a normally functioning three-phase network, the line voltages (voltages between each pair of phase conductors) are equal in magnitude and differ in phase by 120 degrees. Accordingly, phase voltages (voltages between each phase conductor and a neutral conductor) are equal in magnitude and have similar phase differences.

As follows from the above, the phase angles between these voltages are equal to each other. This is called the "symmetric three-phase voltage system." If you connect a symmetrical load to such a network, that is, a three-phase load at which the currents of each phase are equal in magnitude and phase, then such a load will create a symmetrical system of currents (with the same phase angle between them). This is possible provided that in all three phases of the load there are identical reactive and active resistances ...

Recently, the topic of automation of various technological processes using programmable controllers (PLCs) has become increasingly popular. Despite this, there are very few practical articles on the Internet with real examples of how to program these PLCs. This topic is very interesting. Learning how to write PLC programs is possible even without them. The emulation mode, which is available in all modern software packages, helps a lot with this.

In this article I will show an example of translating an electrical circuit built on relay devices (starters, relays) into a program that will work on the controller. I must say right away that this is just a small educational project and does not pretend to explain anything more than just explaining the basic principles of PLC programming with a concrete example. The initial scheme for this project is a relatively simple scheme of a two-story linkage truck hoist ...

In all electrical circuits have to turn on and off the instruments and devices. To do this, use switching devices, it can be either a simple switch or switch, or relays, contactors, etc. Today we will consider one of such devices - a solid state relay, talk about what it is like to select and connect to a load control circuit.

A solid state relay is a device built on semiconductor elements and power switches, such as triacs, bipolar or MOS transistors. In English-language sources, solid-state relays are called SSRs from Solid State Relay (which is literally equivalent to the Russian name).Conventional relays, like all electromagnetic switching devices, work as follows - there is a coil to which current is supplied from the control system or the push-button station.As a result of the current flowing through the coil, a magnetic field arises that attracts the armature ...