At the beginning of the last century, in many cities there was a unique profession - a lamplighter. This was a man who was engaged in street lighting. With the onset of twilight, he lit lights every day, and in the morning extinguished them.

Nowadays, automatic devices called “twilight switches” or “photo relay” deal with lighting issues. Twilight switches are produced by manufacturers with various electrical characteristics, operational parameters and design for various purposes.

They can be designed to work indoors, for example, to illuminate stairwells of staircases or be used outdoors under the influence of precipitation. All photorelays are united by the fact that they work according to a single law ...

A significant part of the energy, for example, in automobiles, is dissipated in the form of heat in the atmosphere, as a rule, it is irretrievable losses associated, of course, with unnecessary expenses. However, the scientist Gang Chen, who works at the Massachusetts Institute of Technology in Cambridge, USA, has set himself the task of using this wasted waste heat to optimize energy consumption.

Traditionally, thermoelectric materials capable of converting the temperature difference into the difference of electric potentials have low energy efficiency, which makes their widespread use impractical. But already in 2004, Gang Chen and Karl Richard Soderbergh, thanks to nanotechnology, significantly improved the efficiency of one of these materials, which made it possible to create more cost-effective thermoelectric devices. In 2008, they improved the thermoelectric converter ...

In residential buildings there are multi-key switch designs that are complemented by an electrical outlet. They are usually installed in the corridor on the partition at the entrance of the doors, for example: a bathroom, a bathroom, a kitchen.

They can be made in the form of vertical or horizontal structures for placement inside installation boxes built into the wall or with a housing for external use.

Such blocks are available for operation in electrical wiring equipped with the following systems: TN-S, TN-C. Sockets for connecting to the electrical circuit of an apartment equipped with the TN-S system have additional contacts for connecting working electrical appliances with a protective zero through a PE conductor, and for structures using the TN-C circuit, the grounding of the housing of household appliances is not used ...

Only two metals - copper and aluminum are widely used as conductors of electric current. Their use as such is determined by the complex physical properties of the metals themselves and their price.

As is known from physics, an electric current is an ordered movement of electric charges in a conductor, under the influence of electric field forces. When moving electric charges in a conductor, they undergo a counteraction, which is estimated by the value of electrical resistance and which is measured in ohms (Ohms).

The electrical resistance for cylindrical conductors is determined by the formula r =ρ* l / s,  where r - electrical resistance of a conductor, Ohm,ρ - electrical resistivity of the conductor material, Ohm * mm2 / m,l -conductor length, m, s - cross-sectional area ...

October 26, 1896, a 35-year-old native of the American city of Murray, Kentucky, self-taught experimenter, farmer Nathan Beverly Stubblefield applied for a new patent. This patent was supposed to be the third patent of the inventor after the two previous ones.

Previous patents were for a lighter for kerosene lamps and a mechanical telephone, which he received several years ago. In this case, the subject of patenting was a special electric battery, an earth battery. The inventor took a rather original approach to using a volt pair as the basis for creating a new class of current source.

As you know, a galvanic effect occurs when a galvanic pair is immersed in moist earth or water, which allows electricity to be supplied to an external circuit of very low power. Significant current could not be obtained from such a source ...

2001 year. A familiar master entrepreneur brought a vertical loading washing machine from Germany, which had worked out factory guarantees in a German family, and offered to buy it for neighbors with a significant discount and bonuses: a free installation and its 3-year warranty.

We made an agreement and paid the money. The purchase was placed in the kitchen. For seven months the machine worked amazingly, and then, at the most unexpected moment, it flowed while washing the laundry.

It is good that the hostess was at home and from the remote room I heard the sound of pouring water that filled the floor in the kitchen. In addition, the car "shocked" the hostess when she approached her. Naturally, they flooded the neighbors from below. The called master fixed the malfunction and paid for the repair of two apartments without further questions, and the car still works after this incident. The cause of the leak is simple: during a preventive replacement ...

Nearly thirty years of searching for ways to improve the aluminum-ion battery is nearing its end. The first battery with an aluminum anode, capable of quickly charging, while being inexpensive and durable, was developed by scientists from Stanford University.

Researchers confidently state that their brainchild could well become a safe alternative to lithium-ion batteries, used everywhere today, as well as alkaline batteries, which are environmentally harmful. It will not be superfluous to recall that lithium-ion batteries sometimes ignite. Chemistry professor Hongji Dai is confident that his new battery will not light up, even if it is drilled through. Professor Day's colleagues described the new batteries as “ultra-fast rechargeable aluminum-ion batteries”. Due to its low cost, fire safety, and the ability to create significant electrical intensity, aluminum has long attracted attention ...

If you decide to make repairs in the kitchen or just moved into a new apartment, then this is the right time to distribute the wiring and consider how best to hide the various wires. Manufacturing companies that are engaged in the production of kitchens in rare cases suggest making a plan when measuring a wiring diagram that will correctly distribute the outlet points of outlets throughout the kitchen for private use, as well as for connecting equipment.

A large number of extension cords in the kitchen always spoil the attractiveness of the interior, and even more so interfere. A large number of extension cords in the kitchen always spoil the attractiveness of the interior, and even more so interfere. For this reason, you initially need to outline where the sockets will be. If you do not plan to transfer them in the future, then it is better to drown the electrical wiring in the wall, having probed it. But not everyone has the opportunity to carry out this type of work.Consider other options to hide the wires ...