What is an induction cooker, principle of operation, pros and cons, diagram

An induction cooker is one of the types of kitchen ovens, the principle of which is to heat the dishes with induced eddy currents. The latter are created due to the action of an electromagnetic field with a frequency of 20 to 100 kHz.

The induction cooker consists of a casing, a control board, a temperature sensor, a power section, its control circuit, and a pulse controller.

Induction type furnaces differ in design features, dimensions, type of embedding in furniture, as well as in a set of heating elements.

What are the advantages?

The induction cooker has a number of advantages that distinguish it from competitors.

Of the main:

• Maximum efficiency due to the start of heating the dishes immediately after switching on, and this saves electricity;
• Reliable protection against “wrong” dishes. The burner will not turn on if there is a pan or pan with a non-magnetic bottom on the stove;
• Automatic shutdown when removing dishes;
• Maintaining the set temperature at a certain level. This is due to the fact that the control sensor is not affected by the high temperature of metal products;
• Stable power, which does not depend on the voltage of the household network;
• A wide range of programs that allows you to cook dishes of varying complexity;
• The induction surface is heated only from dishes, so the likelihood of burns is extremely low;
• No unpleasant odors;
• Ease of maintenance. Most modern models have a glass surface, the processing of which is not difficult. Outside, the dishes do not burn due to the absence of open flames and hot surfaces.

Among the shortcomings, it is worth highlighting the high power, which creates an additional load on the wiring, the presence of electromagnetic radiation and the possibility of using only special dishes.

In addition, if all the burners are turned on at the same time, they will not give out full power.

What types of induction cookers are there?

On sale there are the following types of induction cookers:

• Portable (desktop). They are small in size and have one burner;
• Built-in – combined with furniture in the kitchen;
• Combined. There are plates on which one half of the burners works according to the standard electric, and the second – according to the induction principle.

Driving.

What is different from other plates?

Induction cookers compare favorably with other types of stoves (gas and electric).

It is worth highlighting a number of points:

• The efficiency of induction type furnaces reaches 90%. For comparison, in gas stoves this figure is only 30-60%, and in electric stoves – no more than 70%;
• High heating rate (devices with heating elements or gas burners cannot boast of this feature);
• Efficiency. After removing the dishes, the work area does not need to be turned off manually – this happens automatically. In electric or gas stoves, the burner continues to work, which leads to an overrun of gas and electricity. In summer, this is especially important, because there is additional heating of the air, which complicates the process of air conditioning (cooling) of the room;
• Precise temperature control. On stoves with heating elements or those operating on gas, temperature control occurs “by eye”. In the case of induction cookers, it is possible to maintain the same parameter during the entire cooking time;
• Safety. If a person accidentally mixes up the dishes and puts the product with a non-magnetic bottom, the burner will not work. To activate the burner, the dishes should cover its area as much as possible, from 50% or more;
• Many additional features that classic gas or electric stoves cannot boast of.

The principle of operation of the induction cooker

Before using an induction stove, it is advisable to understand the principle of its operation. It is built on electromagnetic induction – the mechanism of the flow of electric current when the magnetic flux changes.

An induction hob is similar in principle to a transformer. Under the glass-ceramic surface of the device is an induction-type coil, under which a current flows with a frequency of 20 to 100 kHz.

The role of the primary winding is played by an induction coil, and the secondary is the dishes installed on the burner.

As soon as the product is placed on the work surface, induction currents appear, heating pans, pots and other cooking products.

As for the glass-ceramic surface of the stove, it also warms up, but from the dishes, and not from the working area.

With regard to the principle of action, it is worth highlighting a number of points:

1. Power regulation

As noted above, the dishes are heated by high frequency eddy currents acting on them. At the same time, the power of the burner can be adjusted in two ways – pulsed or continuously.

In the first case, the stove will periodically turn on and off. Depending on the installed power, the frequency of operation also changes.

At the maximum power parameter, the frequency reaches 50-100 kHz, and in case of its decrease – 20 kHz.

2. Heating area

The principle of operation of the induction cooker is designed in such a way that the surface near the heating zone remains cold, and this reduces the risk of burns.

As for the heating elements used, they are of several types:

• Tape. They have the form of a tape, twisted according to the principle of a spring. Heating time is 8 seconds;
• Spiral. By the name, you can judge the design of the part. The surface heats up within 15 seconds;
• Halogen. Such a heater has the form of a tube that is filled with halogen gas. Inside there is a special heater (it is through it that the current passes). Thanks to this principle of operation, there is an almost instantaneous heating of the dishes after switching on. The maximum temperature is reached 3 seconds after switching on;
• Induction. Such devices create a high-frequency field that heats the bottom of the dish.

3. Features of cooking on an induction type oven, which dishes are suitable

As noted earlier, for such a stove it is worth getting special dishes with a magnetic bottom.

The oven automatically recognizes a suitable design and immediately activates when the burner knob is turned.

It is allowed to use dishes:

• From cast iron;
• From stainless steel;
• Enameled, with a flat bottom.

If the bottom of the dish is made of steel, but there is a layer of enamel on it, the use of such a product is allowed. This is due to the fact that the magnetic field does not “break through” the enamel layer.

Harm to health

Today there is a lot of discussion regarding the harm of induction cookers, because the principle of their work is based on electromagnetic fields, the negative effect of which is well known. Many experiments have been carried out on this subject.

Scientists have proven that at a distance of one centimeter from the source, electromagnetic radiation is always above the permissible ICNIRP norm.

If the pan is offset relative to the center of the work surface or if its diameter is smaller than the diameter of the burner, the indicated indicator will be more than normal at a distance of up to 12 cm.

This parameter is typical for cases where special utensils are used for cooking. If there is an enameled object on the work surface, the danger zone is larger – up to 20 cm.

Why is it dangerous for health?

The electromagnetic field that occurs near the human body can lead to the appearance of induced currents in the body and negative effects on the central nervous system. To protect health, ICNIRP has set requirements for upper current limits.

To make sure that induction cookers meet such standards, a study was conducted with the participation of a group of volunteers of various ages and genders.

People were located in the immediate vicinity of the cooking surface (at a distance of five centimeters). Scientists at that moment studied the currents that flowed in the body and the central nervous system of the body.

It has been proven that the current values ​​in the case of built-in models are minimal.

As for portable models, their current indicators are higher, but they also did not exceed the established norm.

It is worth noting that the limit set by ICNIRP is 50 times less than the minimum threshold at which stimulation of the human CNS occurs.

What is the outcome of the study?

Experts published the results of the experiments, but admitted that there is still not enough information about the dangers of electromagnetic fields. It is important to understand that the nature of such radiation may vary depending on the nature of its occurrence.

There is another study, the results of which can be found on the WHO website.

People and animals took part in the experiment, but it was not possible to prove the negative effect of electromagnetic radiation on the central nervous system or the cardiovascular system.

Recommended Use

Users who have opted for an induction hob should take into account the following points:

• Do not use dishes with obvious signs of damage, as well as those with a convex bottom;
• It is desirable that the pots and pans used cover the working surface of the burner. In this case, the dishes should be located exactly in the center of the heating area;
• During the operation of the induction cooker, stay away from it and do not touch the surface;
• When buying cookware, pay attention to special marks in which the manufacturer notes the possibility of using products on an induction type stove;
• When mixing food, use non-metallic cutlery.

Malfunctions of induction cookers

The electromagnetic principle of operation of the induction cooker implies high reliability and durability of the device.

Despite this, during operation, some breakdowns are possible:

• Low burner power. The likely cause is improper installation of dishes that are not in the center of the work surface. It is possible that the diameter of the pot (frying pan) is smaller than the diameter of the heated zone. Also, the reasons include the incomplete fit of the dishes to the surface or overheating of the induction winding;
• The burners on the left side of the oven do not work. The probable cause is a breakdown of the control unit or power board;
• Failure of one of the working areas. Before cooking, it is important to follow a certain switching sequence. First, the hotplate is selected (using the touch panel), and then the power is set. If everything is done correctly, check the used cookware for the fact that it matches the induction cooker (in diameter and material). If the cookware complies with the rules, but the comfort still does not work, activate the test check of the temperature sensor and replace it (if necessary). If the sensor is working, make sure that the dishes fit snugly against the surface;
• The two burners on the right side are not working. The cause of the malfunction often lies in poor contact of the terminal box or blown fuse. It is worth checking the quality of the connection between the control unit and the power board. In extreme cases, a replacement block is required;
• The residual heat indicator is out of order. Actions – conducting a test check, the results of which conclude that the temperature sensor is in good condition. If the part is serviceable, the control unit changes. In case of display malfunctions, it is worth checking the quality of the connection between the panel and the control unit;
• The hotplate does not turn on and there are no messages on the screen. Check the power switch, fuse, as well as the quality of the connection of the control unit with the power board and the touch panel;
• Cooling fan failure. Pay attention to the installed power. If it is minimal, the fan will not work immediately, but after reaching an air temperature of 50 degrees Celsius. Do a test check. If the fan fails, replace it. If this node is serviceable, replace the control unit;
• The induction cooker beeps continuously. The probable cause is the failure of the control unit;
• The maximum power burner (3 kW) does not work. The activation of the cooking zone is sometimes blocked to prevent overheating of the induction hob unit. If the problem appears for no reason, the control unit changes;
• Automatic switch off of the hob. The principle of operation of the induction cooker is designed so that the shutdown is performed in three cases. First, if the time was set by a timer. Secondly, if the burner has been running for more than two hours. Thirdly, when after 10 seconds after turning on, no action occurs.

What the market offers, the main manufacturers

Below is a brief overview of today’s most popular manufacturers and some products.

Skvara

This developer brings to the market professional induction cookers that can be used in cafes and restaurants.

Their advantages include greater efficiency, the fastest heating of dishes, the presence of a timer and temperature controller, as well as ease of maintenance.

Here are some manufacturer’s models:

• 2-burner induction cooker Skvara Sif 2.4 for 4 kW.
• Stove FROSTY BT-E35.
• Professional oven Skvara Sif 4.8.

Electrolux

The most popular models of induction furnaces from Electrolux include:

Gorenje

This manufacturer is worth highlighting the following models:

Hansa

This manufacturer offers a wide selection of cookers, among which there are induction-type products. One option is the Hansa FCIW58277 oven with a heat indicator.

The surface is made of glass ceramic. The number of hobs is 4. An electric oven for 65 liters is provided. The width of the product is 0,5 m. Additional functions include convection.

Saturn

The brand’s products are distinguished by an affordable price with a relatively high quality. Of the manufacturer’s induction cookers, it is worth highlighting the Saturn ST-EC0187.

There is only one induction burner. The surface is made of glass ceramic. Additional functions are not provided.

Bosch

The German company is well known in the market for the high quality of its products. Steel and stoves on the induction principle are no exception.

Basic models:

Hotpoint-ariston

Another brand deserves no less attention – Hotpoint-Ariston. Consider some manufacturer models:

Whirlpool

Experienced housewives prefer Whirlpool products. The main models of induction furnaces:

Zanussi

The Italian brand has become famous all over the world for the high quality of its products.

Induction cookers from this manufacturer are also in high demand. Consider the following models:

Siemens

The German manufacturer is no less known for the high quality of the induction cookers on the market. One of the models is EH645BA68E.

This is an oven equipped with a glass-ceramic surface. It has four burners, touch control is provided. The body is made in black. Dimensions (W*D) — 60,2*52,2 cm.

Samsung

Samsung products are rightfully in high demand due to the affordable price of products and high quality.

Brand induction cookers are another confirmation of this. Consider the following models:

Indesit

If we consider the manufacturer Indesit, it is worth noting the VIX 644 CE model.

Features — black color, four heating elements. The principle of operation of the stove is induction. Dimensions – 59 * 51 cm.

Results – the pros and cons of induction cookers

An induction cooker is a reliable assistant in the kitchen, which compares favorably with classic gas or electric ovens.

The main advantages of the product are obvious – maximum efficiency, saving electrical energy and minimal risk of burns.

It is impossible not to note the modern appearance of the product. Such a stove will decorate any kitchen, and it is not difficult to take care of it.

In addition, after removing the frying pan or pot from the heating element, the oven automatically turns off, which eliminates the waste of energy.

Food cooked on such a stove is safe and has maximum health benefits.

Additional conveniences include the ability to control the temperature and the presence of several cooking programs.

Among the shortcomings, it is worth highlighting the need to use special dishes (made of glass or aluminum based on ferromagnetic materials), as well as a high price when compared with the main competitors.

That is why the average buyer cannot afford such costs.