When planning electrical work, in particular when it is necessary to select cable and wire products, the question arises of choosing between a flexible and a hard cable. In this article, we will consider which cable is better: flexible or rigid, depending on local conditions.

First, consider what a flexible and rigid cable is. The flexible cable is multi-core, which provides it with sufficient flexibility. A rigid cable is single core, that is, its conductive core consists of one conductor.

The main distinguishing feature of a flexible cable from a rigid one is the possibility of bending it an unlimited number of times, as well as the ease of bending. Mono-core cable is not intended for frequent bends, it can be bent a certain number of times, after which its conductive core will break. For example, a new copper hard cable is able to withstand ...

Reed sensors are common as sensors for opening doors and windows, to protect against intrusion into objects, in security systems. These magnetic contact sensors are installed on doors, gates, windows and any other massive structures and objects that need to be protected from unwanted opening, movement, or destruction.

Reed switch (sealed contact) is the main element of such a sensor, and makes it a reliable, safe, and durable, at low cost, component of security systems.

The reed switch is a hermetically sealed glass cylinder, in which two permalloy contacts are usually placed, and the medium inside the cylinder is high pressure nitrogen, which eliminates oxidative processes inside this important electronic component. Its contacts are coated with special metal, such as molybdenum, titanium, tungsten ...

Premises that are located below the zero level of the basement of the building are called basements. They are surrounded on all sides by earth, which provides relative temperature stability throughout the year and, as a rule, are deprived of natural light.

Basement operating conditions are associated with increased humidity. It arises as a result of: the proximity of groundwater and the technical difficulties of creating building structures that are tight on all sides, condensation from the air coming from the street into the room when it is cooled.

The applied measures to combat humidity, based on the removal of groundwater, ventilation, the use of exhaust or fresh ventilation systems are not always effective. They partially increase air dryness. Therefore, basements are classified as premises ...

With the development of technologies for the production of low-cost electricity based on solar panels, as well as taking into account significant investment in wind energy, there is a need for a more convenient and technologically intelligent way of storing the received energy. Research results from Linkoping University in Sweden, published in Science, have shown that biological waste paper production can help create affordable, environmentally friendly material for a new type of battery cathode.

Inexpensive organic solar cells based on conductive plastic have achieved very high productivity, and the alternative energy obtained in this way on an industrial scale has now become much cheaper, and there is competition justified by progress. Traditionally, metal oxides carry charge in batteries.Commonly used materials, such as cobalt, for example, are a resource ...

Since childhood, we have known the button above the door to an apartment or building. When you click on it, the owner is given a sound signal - a melodic ringing of a bell or a simple musical composition warning about the appearance of a guest. This is how an ordinary electric bell works. We will disassemble its design without affecting electronic models on multivibrators, microcircuits, and other components.

The electric bell has existed for two centuries, uses the energy of the electromagnetic field. His household designs work on current: a constant value and with a variable sinusoidal harmonic, usually powered by a voltage of 220 volts. To create sound waves, the impacts of a small malleus are used in the form of a steel ball located at the end of a springy plate, which, when mechanically vibrated, strikes the bell. Voltage source in the circuit ...

To build highly functional panels with exceptional flexibility in the design of automatic control and protection systems, modular relays for various purposes are used. They make it possible to create reliable and functional solutions for almost any object. Compliance with the standard (modularity) in terms of component sizes allows you to supplement functions, combine in a new way, and improve an already installed system by adding, for example, new modules to a DIN rail. Consider what modular relays are, and what they are used for.

Impulse relays. When applying a short-term control pulse, the relay is activated by switching the power contact. This is a bistable relay that serves to control the on and off of electrical circuits from different places. A typical example of the use of such a relay ...

When repairing or building, many apartment owners are wondering how to properly place switches or sockets in the apartment. Indeed, not only the convenience of using them depends on this, but also the safety of operation, and, consequently, health.

In order to deal with this issue correctly, we will consider the rules for their placement that existed in the recent past and the new trends that came from other countries.

In Soviet times, it was customary to install lighting switches in residential buildings near the entrance to them at the height of the shoulders of an adult or placed under the ceiling. And the sockets were mounted in the wall at a distance of 90-100 cm from the floor. Wall switches were located at a level of about 160 ÷ 180 cm from the floor. This distance was considered the most suitable, optimal for controlling light. Example of placement of the switch block ...

A thousand years before the first observations of electrical phenomena, mankind has already begun to accumulate knowledge about magnetism. And only four hundred years ago, when the formation of physics as a science had just begun, researchers separated the magnetic properties of substances from their electrical properties, and only after that they began to study them independently. This laid the experimental and theoretical foundation, which, by the middle of the 19th century, had become the foundation of a unified theory of electrical and magnetic phenomena.

It seems that the unusual properties of magnetic iron ore were known as far back as the Bronze Age in Mesopotamia. And after the beginning of the development of iron metallurgy, people noticed that it attracts iron products. The ancient Greek philosopher and mathematician Thales from the city of Miletus (640−546 BC) also thought about the reasons for this attraction, he explained this attraction by the animation of the mineral.Greek thinkers presented themselves as invisible couples ...