Sometimes lighting engineering presents surprises: an unsuccessful light source gains so much popularity that leading lighting companies are engaged in its mass production. It is a question of lamps of arc mercury-tungsten (DRV).

Structurally, a mercury-tungsten lamp is a discharge mercury burner similar to DRL lamps. But in addition, a tungsten spiral is mounted in series with the burner in the bulb. It is located in an external flask, in an argon atmosphere, and serves as a current-limiting element for the burner. Such a lamp does not require external ballast equipment (PRA) and can be directly installed in the lamp instead of incandescent lamps. It was this opportunity that led to the commercial success of DRV lamps. The point here is not only the poverty of enterprises in the CIS countries - the demand for this type of lamp is very high ...

Magnetic starters, as the name implies, were conceived as a switching device for starting electric motors. Therefore, the number of power poles of these devices is almost always equal to three - in terms of the number of network phases. Starters are often equipped with thermal overload relays and a housing with “start” and “stop” buttons.

But the starter turned out to be a very convenient and functional thing. A wide range of rated currents, small dimensions and the possibility of autonomous installation outside of any switchgear or switchboard have led to the fact that magnetic starters have been widely used in everyday life for connecting various powerful electric receivers, for example, heating boilers, to the network.

Like any other electrical device, the magnetic starter periodically also needs repair and maintenance. The magnetic starter maintenance program is simple and includes ...

To begin with, the OEL-820 power load optimizer is the newest type of device familiar to specialists - the non-priority load disconnect relay, and the only one in the world designed for domestic use. Therefore, we will consider the traditional and new device, as a group of devices that solve the same problem.

For different manufacturers, these devices are also called: priority relay, non-priority load relay, priority load relay, etc.

Priority switchboards help in a situation when, when several energy-intensive consumers are turned on, the total power consumed by them exceeds the limit of allowed power. Priority switchboards are installed at the input to the electrical panel. Their principle of operation is to continuously monitor the power consumed by all consumers used ...

In industrial power supply, the term is used in the form of a simple abbreviation: ABP. Automatic input of power reserve is possible if there is an additional, backup source of power supply. In fact, such a backup source most often becomes an additional backup line, generator or battery installation. Automatic transition to backup power is carried out using relays or special electronic units.

But for a household network, such things seem superfluous: relays, electronic components, a backup line, a generator set ... It's cheaper and easier to sit without electricity, or in the light of a flickering lamp that suffers from unstable or undervoltage. However, it should be remembered that the household network of an apartment or private house in the vast majority of cases is single-phase. And the power line is almost always three-phase ...

The most common use of capacitors is the connection between individual transistor stages, as shown in Figure 1. In this case, the capacitors are called transient.

Transient capacitors pass the amplified signal and prevent the passage of direct current. When the power is turned on, the capacitor C2 is charged to the voltage at the collector of the transistor VT1, after which the passage of direct current becomes impossible. But the alternating current (amplified signal) makes the capacitor charge and discharge, i.e. passes through the capacitor to the next cascade.

Often in transistor circuits, at least in the audio range, electrolytic capacitors are used as transient ones. The rated values ​​of the capacitors are chosen so that the amplified signal passes without much attenuation ...

In previous articles, we briefly talked about the operation of capacitors in AC circuits, how and why capacitors pass alternating current. In this case, the capacitors do not heat up, power is not allocated to them: in one half-wave of the sinusoid, the capacitor charges, and in the other, it naturally discharges, while transferring the stored energy back to the current source.

This method of passing current allows you to call the capacitor a free resistance, and that is why the capacitor connected to the outlet does not make the counter spin. And all this is because the current in the capacitor is ahead of exactly 1/4 of the time the voltage applied to it.

But this phase advance allows not only to “trick” the counter, but makes it possible to create various circuits, for example, generators of sinusoidal and rectangular signals, time delays and various frequency filters ...

The search for alternative sources of electricity has become widespread in recent decades. The threat of depletion of fossil energy resources has stimulated research on the use of renewable resources: energy from air, water, and geothermal heat.

The army of inventors joined the scientists working in the field of alternative energy, and today they “flooded” the information space with projects for obtaining “free” energy. One of the most popular areas of their development is the use of atmospheric electricity. Observing the violence of the elements during thunderstorms, there is a great temptation to tame the electric forces of the Earth, to use them for the benefit of man. Let's try to assess how realistic it is to get close to these forces and use them in practice. To begin with, we will answer the question of whether the Earth's electricity reserves are really large? ...

The article discusses the reasons for the weak interest of enterprises and the population in the transition to multi-tariff, time-differentiated metering of electricity.

We rarely think that electricity is the most perishable product known to mankind today. If it is not used immediately, then in a moment it disappears, and with it the uselessly burned gas, coal, heat of TVELs at nuclear power plants. Therefore, a balanced energy consumption is the main task and a headache for energy.

It is possible to compensate for seasonal variations in energy consumption by power plants. But to smooth the diurnal fluctuations - such a task for generating stations is practically impossible. This problem must be solved by consumers: enterprises and the population. To this end, in the CIS countries for many years trying to introduce electricity metering at tariffs ...

If we consider a direct current, then it can not always be perfectly constant: the voltage at the source output may depend on the load or on the degree of discharge of the battery or galvanic battery. Even with a constant stabilized voltage, the current in the external circuit depends on the load, which confirms Ohm's law. It turns out that this is also not quite a constant current, but such a current cannot be called variable either, since it does not change direction.

A variable is usually called a voltage or current, the direction and magnitude of which does not change under the influence of external factors, such as a load, but is completely "independent": this is how the generator generates it. In addition, these changes should be periodic, i.e. repeating over a certain period of time called a period. If the voltage or current changes anyhow, without worrying about the frequency and other regularities, such a signal is called noise ...

The issue of saving electricity and money to pay for it is becoming increasingly acute, especially with the introduction of social norms for electricity consumption. Therefore, citizens, homeowners and business leaders have to look for reserves to reduce electricity consumption.

However, it is impossible to completely abandon the use of energy-intensive electrical appliances - the traffic of which creates the bulk of the electricity bill. Therefore, you have to compromise in order to spend less energy (money) and maintain an acceptable level of comfort. However, one cannot deceive physics, and they have not yet learned how to get the energy of their air. And, therefore, the law of conservation of energy must be strictly observed. This means that if energy has increased in one place, then in some other place it has decreased by the same value. More recently, we talked about a new energy-saving device. ...

Why is this required? Most split systems are designed to operate at an outdoor temperature of -5º C. And this is in the best case, moreover, in heating mode.

As experience shows, nowadays household air conditioners are very often used for cooling in winter in server rooms as well as in technical rooms where working equipment is located. As a rule, it should work smoothly, in any weather. Very often they are cooled by air conditioning in offices - after starting central heating, the rooms become stuffy, thermostats on heating batteries are not everywhere, or they are not used, just turning on the air conditioning.

Why can't household air conditioning work in winter? There are several problems that get in the way of using an air conditioner in the cold. Starting a cold compressor ...

Putting an electric panel on the street is not such an absurd idea as it might seem. The reasons for this technical solution are as follows:

Energy sales organizations often insist that the meter for energy consumption and, accordingly, the introductory home electrical panel, be located within the reach of the inspector. This is especially true for large suburban residences, where the owners can relatively easily “hide” in the house an additional input past the counter with known goals. On the other hand, the shield on the street support is clearly visible from all sides and does not cause the inspector any doubt or suspicion.

In the same suburban residence, an opening electric shield can also be very impressive. And the desire to save on space and take out at least an accounting device and input ...