When it comes to choosing a multimeter, the user is faced with a problem. Which multimeter is suitable for its various purposes? After all, the assortment of measuring instruments of this type is quite wide today, multimeters with more or fewer functions are on the market, some are more expensive and some are cheaper, but the choice should be made not to buy the first one that catches your eye.

For household purposes, the device is simpler, and for repair and laboratory work related to the diagnosis of electronic devices and maintenance of industrial equipment, you will need a professional multimeter. Let's compare the difference between a household multimeter and a professional one, and what tasks this or that class of this device will solve. As a household multimeter is very popular ...

It would seem that just recently, having opened any apartment shield, you could find there only a counter with a couple of traffic jams, but modern panels have already gone quite far from their Soviet predecessors. The same compact machines, in much larger quantities than steam, and other electrical equipment, are now mounted in panels exclusively on a DIN rail.

Many modular elements, such as starters, relays, controllers, switches, timers, RCDs and more, can be assembled into blocks today by mounting them on a DIN rail - a brilliant invention of the German Institute for Standardization. This is a simple-looking perforated or solid profile made of steel or aluminum, characterized by the current of the ground terminal, strength and weight. DIN rails are available in different lengths, they can be divided into shorter pieces as needed, for this a marking in the form of a notch can be applied to a long rail. DIN rails and profile shape vary ...

The safety of using electric energy depends not only on the correct installation of the electrical installation, but also on compliance with the requirements laid down in the regulatory documentation for its operation. The grounding circuit of a building, as part of protective electrical equipment, requires periodic monitoring of its technical condition. In the normal power supply mode, the ground loop of the PE conductor is connected to the housings of all electrical appliances, the potential equalization system of the building and is inactive: through it, roughly speaking, no currents pass, except for small background ones.

In the event of an emergency related to the breakdown of the insulation layer of the wiring, hazardous voltage appears on the body of the faulty appliance and flows through the PE conductor through the ground loop to the ground potential. Due to this, the value of the high voltage transmitted to the non-conductive parts should decrease ...

At first glance, the winding is a piece of wire wound in a certain way and there is nothing much to break in it. But it has features: strict selection of homogeneous material along the entire length, accurate calibration of the shape and cross section, application of a varnish layer with high insulating properties in the factory, strong contact joints. If at any point in the wire any of these requirements is violated, the conditions for the passage of electric current change and the engine starts to work with reduced power or stops altogether.

To test one winding of a three-phase motor, disconnect it from other circuits.In all electric motors, they can be assembled according to one of two schemes: a star and a triangle. The ends of the windings are usually output to the terminal blocks and are marked with the letters "H" (beginning) and "K" (end). Sometimes individual compounds can be hidden ...

In our daily lives, we constantly encounter various electrical devices that greatly facilitate our activities. Almost all of them have in their design an engine powered by electricity to perform a certain job. Sometimes, for various reasons, malfunctions arise in it. It is necessary to determine its performance, to identify and repair damage.

Immediately make a reservation that we will not resort to complex technical descriptions and formulas, but try to use simplified schemes and terminology. We also take into account that working with electric motors in electrical installations is dangerous. They are allowed trained, trained personnel. By mechanical design, any electric motor can be imaginedconsisting of only two parts: stationary fixed, which is called a statorand attached to the machine body...

The name of this device is made up of three words: “mega”, denoting the dimension of a measurement (thousand thousand or 10⁶), "Ohm" is the unit of electrical resistance, "meter" is the abbreviation of measuring. Immediately it becomes clear the technical purpose of the device: the measurement of electrical resistance in the range of megaohms. Often, connoisseurs of the Russian language correct this word, excluding the letter “a” from it under the pretext that two vowels in a row during pronunciation are dissonant. But this technique distorts the meaning embedded in the device in the same way as the slang of individual electricians - “meger”.

The device is based on the famous Ohm's law for a section of the circuit I = U / R. For its implementation inside the case, any modification has the following built-in: a constant, calibrated voltage source, current meter, output terminals. The design of the voltage generator can vary significantly and can be created on the basis of simple ...

Numerous technological processes requiring temperature control occupy not the last place in industry. Temperature measurement of gases, liquids, bulk powders and solid surfaces - each of these cases has its own characteristics, and for correct measurements it is important that the measurement method is consistent. There are many temperature sensors created on the basis of various physical laws and used for these purposes. There are both special and universal sensors.

The most widely used in industry today are thermoelectric sensors capable of operating in the temperature range from -200 ° C to + 2500 ° C and even higher. These are reliable, high-precision devices, often used to automatically control processes. The operation of the first type of such sensors - thermocouples, is based on the phenomenon ...

One of the most popular series of circuit breakers for high currents (up to 630 A) in power supply systems are A3700 series circuit breakers. Automatic machines are issued in unipolar, bipolar and three-pole execution. They are designed for current protection of electrical equipment during current overloads and short circuits in a wide variety of electrical circuits of alternating and direct current with a rated voltage of up to 660 V (alternating current) and up to 440 V (direct current).

Circuit breakers can also be used for infrequent switching of electrical circuits, as well as to protect these circuits when the voltage drops below unacceptable values.Current protection releases are performed on semiconductor and electromagnetic elements. Mechanical wear resistance of A3700 circuit breakers - 16000 on-off cycles, switching wear resistance ...