It happens that when you turn on a certain electrical appliance in an apartment, such as a multicooker or a lighting system with energy-saving lamps, or the power supply of a particular electrical appliance, the circuit breaker starts to buzz in the electrical panel. And usually this phenomenon is not associated either with the increased power of the connected consumer, or with the corresponding current approaching the rating of the machine. And it is connected with a certain power or with a certain household appliance.

In some cases, the hum completely disappears with an increase in load power, and often the landlord has no complaints about the smell of burning ... So, there is no arc buzzing inside the machine. And then what? Where does this hum come from? Is he dangerous? How to deal with this phenomenon and is it worth it to fight with it at all? Let's think about it. Everyone who is familiar with the circuit breaker device knows that two protective tripping mechanisms are simultaneously implemented inside it: thermal and electromagnetic ...

Household consumers are gradually phasing out incandescent lamps, and they are using them less and less. At first they were replaced by compact fluorescent lamps (CFLs). They consume 5 times less energy at the same brightness. That is, a 20 W fluorescent lamp can replace a 100 W incandescent lamp. For this they were called energy-saving.

Technology does not stand still and in the last 5 years, LED lamps or LEDs have strengthened in the market. The range of products is wide enough from light panels and tapes to searchlights and lamps for all possible socles. At the same time they shine 10 times brighter than incandescent lamps of the same power. Let's take a closer look at the differences between energy-saving and LED lamps. LED lamps actually also belong to energy-saving ones, but in the people this name is fixed to compact fluorescent lamps, although they save energy not like LED ones ...

The relay has a limited resource, this is primarily due to the principle of its operation: the electromechanical relay operates due to the magnetic field and the closure of mechanical contacts. Mechanical contacts wear out, the coil burns out, hence the need for repair. Most often, the repair consists in cleaning the contacts or solving problems with the coil.

Before moving on to repair issues, let's walk through the components of an electromagnetic relay. The relay itself compares the magnitude of the control action, after which the signal is transmitted to the controlled circuit. In our case, an electric current is supplied to the coil. The anchor is attracted to the core of the coil due to the magnetic force created by the magnetic flux. The relay is triggered if sufficient voltage and current are supplied. When the electromagnet trips, the contacts close ...

The transistor appeared in 1948 (1947), thanks to the work of three engineers and Shockley, Bradstein, Bardin. In those days, their rapid development and popularization were not yet anticipated. In the Soviet Union in 1949, the prototype of the transistor was presented to the scientific world by the Krasilov laboratory, it was a C1-C4 triode (germanium). The term transistor appeared later, in the 50s or 60s.

However, they found widespread use in the late 60s and early 70s, when portable radios came into fashion. By the way, they have long been called the "transistor".This name stuck due to the fact that they replaced electronic tubes with semiconductor elements, which caused a revolution in radio engineering. Transistors are made of semiconductor materials, for example, silicon, germanium was previously popular, but now it is rarely found, due to its high cost and worse parameters, in terms of temperature and other things ...

For the Smart Home system, the main task is to control household appliances from a control device, be it an Arduino type microcontroller, a Raspberry PI type microcomputer or any other. But to do this directly does not work, let's figure out how to manage the 220 V load with Arduino.

To control AC circuits, the microcontroller is not enough for two reasons: at the outputmicrocontroller a constant voltage signal is generated, the current through the pin of the microcontroller is usually limited to 20-40 mA. We have two options for switching using a relay or using a triac. The triac can be replaced by two thyristors turned on in parallel (this is the internal structure of the triac). Let's take a closer look at this.The thyristor works as follows: when a forward bias voltage is applied to the thyristor (plus to the anode, and minus to the cathode), no current will pass through it ...

Sensors are used to measure quantities, environmental conditions, and reactions to changes in states and positions. At their output, there may be both digital signals consisting of ones and zeros, and analog ones consisting of an infinite number of voltages in a certain interval.

Accordingly, the sensors are divided into two groups - digital and analog. To read digital values, both digital and analog inputs of the microcontroller can be used, in our case, the ATS on the Arduino board. Analog sensors must be connected through an analog-to-digital converter (ADC). ATMEGA328, which is installed on most ARDUINO boards, contains an integrated ADC in its circuit. As many as 6 analog inputs are available to choose from. If this is not enough for you, you can connect it to digital inputs using an additional external ADC ...

When purchasing a new induction cooker, do not rush to plug it into one of the free outlets. In this case, first of all, it is necessary to determine the possibility of connecting this household appliance to a particular section of the wiring and choose the most optimal way to connect it. Consider the question of how to connect an induction cooker.

It should be noted that before acquiring an induction cooker, it is necessary to clarify which load limit is defined for the apartment (house) and evaluate the possibility of operating a particular induction cooker taking into account its maximum power consumption. A desktop induction electric stove, as a rule, has a cord and a plug for connecting to a regular household outlet. That is, in this case there is no need to purchase an additional cord and plug ...

One of the reasons for this unpleasant phenomenon is explained very simply. Our body is very interesting in matters of electrical safety: on the one hand, with our sensory organs we can’t recognize the presence of a nearby potential of electrical voltage and, at the same time, when we get under its action, we get unpleasant sensations, injuries, and tragic injuries. In such situations, it is customary to say that we are shocked.

Let's try to open this question in more detail, from the point of view of electrical engineering. We will need to take into account the nature of the current flow, the properties of our body, the experience of accidents accumulated by our predecessors, formulated by safety rules. Electric current is the ordered (oriented in a certain way) motion of the smallest particles with charges. It is created under the influence of the applied external forces of the electric field ...