Voltage stabilizers are quite interesting devices. When a long time ago, back in the Soviet era of mass construction of “Khrushchev” and “Brezhnevka” buildings, such a device was almost an obligatory neighbor of the TV: it was believed that plugging the “square friend” directly into the outlet was fraught with danger. Then TVs began to be connected to the network “just like that” - and nothing... Stabilizers turned into relics - but not for long. With the advent of household computers, stabilizers returned and again took their place of honor - this time in the form of blocks with several sockets. Why are voltage stabilizers needed and why are they back? Let's try to answer this question...
Why were they needed yesterday...
Let's start with why voltage stabilizers were once needed... Here the answer is more or less simple - those who moved into new apartments in the 60-70s of the last century may themselves still remember that in the first few months (or even years) voltage fluctuations in the household network deviated greatly from the prescribed 220 volts. What was noticeable to the naked eye was that the light bulbs from time to time began to shine at half power, and sometimes burned out; At the same time, the image on the screen of the still black-and-white television receivers also faded and became barely visible.
The cause of such troubles was, as a rule, the connection of a mass of new consumers to the network, in which the output voltage from transformer substations was divided by a much larger number - and therefore dropped from 220 to 210, or even 200 volts. And vice versa - when consumers disconnected from the network en masse (for example, they turned off everything they could when leaving for work), then the voltage in the network could jump for a long time to 240, or even 250 volts.
In such conditions, voltage stabilizers were indeed necessary. Moreover, the very first of them were not even automatic - they were an ordinary transformer, along the outer winding of which it was necessary to manually move the terminal.
Over time, they gave way to ferroresonant stabilizers, and when switching power supplies began to be installed in color TVs, the need for such voltage stabilizers disappeared altogether - fortunately, strong voltage fluctuations in the city electrical network became a thing of the past. Now these fluctuations usually do not exceed 5%, last no more than a minute and are observed mainly in rural areas.
Why are they needed today?
However, in the late 90s, voltage stabilizers made a comeback. Their return was associated with the massive spread of household computers, for which even short-term voltage fluctuations could be fatal. The demand for voltage stabilizers has again arisen - and multi-socket blocks have again appeared in numerous computer accessories stores...
...which, in fact, very often were not voltage stabilizers at all, since they differed from a set of ordinary sockets only by the presence of a parallel-inserted capacitor (sometimes in combination with an inductor). Which could indeed “cut off” individual voltage fluctuations at a total frequency of 50 Hz - but that’s all. However, for the majority personal computers, also equipped pulse blocks power supply (UPS), that was enough.
It’s paradoxical, but true - it’s precisely the most, at first glance, “delicate” devices - computers and televisions - that tolerate voltage fluctuations in the network best and least of all need real voltage stabilizers.
Nevertheless, there are electrical appliances that need a voltage stabilizer in our homes - and in considerable quantities. These are, first of all, new refrigerators of the latest models - they often have microprocessor control, which should ensure efficient operation of the compressor. And microprocessors do not tolerate voltage surges very well. The same picture is observed with washing machines– especially those that are designed to operate at 380 volts. Microwave ovens and dishwashers also do not tolerate voltage surges well. Well, don’t forget about electrical appliances in dachas and country houses- including those responsible for the operation of heating boilers.
How do stabilizers work?
In general, the principle of operation of voltage stabilizers remains the same as it was: they are still a transformer, one winding of which is supplied with electricity from the outlet (which can have a voltage of 198 and 240 volts), and the other is “removed” exactly 220 volts. Required voltage this is obtained by changing the number of turns on the “home” winding from which the voltage is supplied.
Therefore, in essence, the main difference between voltage stabilizers comes down to how exactly the working number of turns on the “home” winding will change - smoothly or abruptly.
Voltage regulation “intermittently” is provided by relay stabilizers.
In such stabilizers, conclusions are made on the “home” winding to relays designed for 220 volts. If the “home” voltage is above 220, then several relays are turned off, reducing the number of working turns on the home winding - and the “home” voltage drops. The relay operation speed is from 10 to 20 milliseconds, and the increase-decrease in voltage with each operation can be different models stabilizers from 1 to 5 volts.
The main advantage of relay stabilizers is the reliability and simplicity of design, and the main disadvantage is some self-consumption. After all, the “home” current passes through the windings of all relays and is consumed at the same time - and the more relays in the circuit, the greater the consumption.
Smooth voltage regulation can be provided by thyristor stabilizers, the circuit of which will look something like this.
From the diagram it is easy to see that a thyristor stabilizer is, in fact, also a converter of alternating current to direct current and vice versa. The smoothness of its operation is purchased through the use of much more much more expensive parts.
So which voltage stabilizer to prefer in specific conditions is up to you to decide.
Whatever type of voltage stabilizer is, its mission is to protect electrical appliances from poor quality AC voltage. Maximum deviations from the norm of 220V, according to GOST, should be plus or minus 10%. These standards are clearly too high, but even domestic energy companies manage to ignore them. In this regard, standard domestically produced stabilizers keep the input voltage within 150–260 V.
A voltage stabilizer becomes an urgent necessity when low voltage continually stops operation or prevents the refrigerator from starting, causes the TV image to ripple, etc. By and large, all electronic household appliances require voltage stability, and this need increases the more the equipment is crammed with electronics. And this is present, for example, in the so-called. economical lamps, which not everyone knows about.
In the conditions of our electrical network, it is undesirable to use devices designed for consumers from European Union countries. As in the CIS countries, in Russia a 10% difference with the “classical” voltage of 220V is considered acceptable. Domestic electrical appliances are produced based on these indicators. Thus, even if the voltage is 198-242V, all these units should work without failure. The standards of European countries are more stringent, and there is less variation here. As a result, the characteristics of electrical equipment released for Europe do not correspond to the parameters of our electrical networks.
If there are no visible “symptoms” of abnormal voltage, but there are doubts, a simple tester for a few dollars is enough to measure network performance. This is easy to do even for those who have never dealt with this device. It is best to take measurements over several days (preferably on both weekdays and weekends); the time of day should also be different. In accordance with the tester’s readings, one or another decision is made on the advisability of installing a stabilizer.
A voltage that does not go beyond the range of 205-235V means that stabilizers can be supplied only for the most expensive and most important devices. If the voltage is more or less than the range of 205-235V, if it changes sharply, if you can see that the light is blinking, but at the same time it remains within the range of 195-245 V, then the “indications” for installing a stabilizer are as follows: for lighting sources its presence mandatory, for all other devices - very, very desirable. And finally, the presence of a stabilizer is an urgent necessity if the voltage values were less than 195 or more than 245 V, if over the course of one day the voltage jumps from minimum to maximum.
It will be useful to know that a voltage of 198V or 242V, which is considered the norm by domestic standards, actually leads to the fact that household appliances “live” significantly less than the time allotted to them. Moreover, “old age” occurs the earlier, the more electronics are used in the device. Wear increases significantly when the voltage goes beyond this range. It is low voltage that is responsible for fairly common refrigerator breakdowns. If the voltage remains stably at 160-190 V, then this equipment may refuse to work just a year after the start of use - and such situations are not something out of the ordinary. The stabilizer will help to significantly increase the service life of household appliances.
Many people have experienced sudden power surges, as a result of which all household appliances in the house fail. Is it possible to somehow prevent them and protect expensive devices from damage? In this article we will look at, what they are and how they work.
Modern electrical networks, unfortunately, do not provide constant voltage at the outlet. Depending on the place of residence, the number of subscribers and the power of devices on one line, the voltage can vary greatly from 180 to 240 volts.
A modern stabilizer looks like this
But most of today's electronics have an extremely negative attitude towards such experiments, since the limit for it jumps to +-10 volts. For example, a TV or computer may simply turn off if the voltage drops to 210, which happens quite often, especially in the evening.
There is no reason to count on the power grids being modernized in the coming years. Therefore, citizens need to independently take care of “equalizing” the voltage and protecting power grids. All you need to do is purchase a stabilizer.
What it is
A stabilizer is a device that equalizes the voltage in the network, supplying the necessary 220 volts to the device. Most modern inexpensive stabilizers operate in the range of +-10% of the desired value, that is, “evening out” surges in the range from 200 to 240 volts. If you experience more serious subsidence, then you need to select a more expensive device - some models are capable of “pulling” a line from 180 volts.
Modern voltage stabilizers This small devices, which work completely silently and do not buzz, like their “ancestors” from the USSR. They can operate on 220 and 380 volt networks (must be selected upon purchase).
In addition to voltage drop, high-quality stabilizers “clean” the line from junk impulses, interference and overloads. We recommend that you definitely use such devices in your home, installing them at the entrance to your apartment or, at a minimum, on every important household appliance (boiler, work computer, etc.). But it’s still better not to risk expensive equipment, but to purchase a normal leveling device.
Now that you knowthink about how much money it can save you. Works in the apartment at the same time a large number of technology - washing machine, computer, TV, dishwasher, phone charging, etc. If a surge occurs, then all this can fail, and damage will be caused to tens, or even hundreds of thousands of rubles. It is almost impossible to prove in court that the cause of equipment failure was a power surge, so you will have to pay for repairs and buy a new one with your own money.
The principle of operation of the stabilizer Types of stabilizers
On this moment There are three types of stabilizers, differing from each other according to the principle of alignment:
- Digital.
- Relay.
- Servo driven.
The most practical, convenient and reliable are digital or electronic devices. They work due to the presence of thyristor switches. The main advantage of such systems is minimal response time, absolute noiselessness, and small size. The downside is the price; they are usually 30-50% more expensive than other devices.
Relay systems belong to the middle price segment. They work by switching power relays that turn on and off the corresponding windings on the transformer. Relay voltage stabilizers for home are considered optimal. The main advantages of the device are affordable prices and fast response speed. Disadvantage: short service life. A conventional relay can withstand approximately 40-50 thousand switchings, after which the contacts wear out and begin to stick. If you have a fairly stable network, then the relay system will work for you for several years. But if failures happen several times a day, then it can fail in one and a half to two years.
Servo-type devices are low cost and operate by changing the number of turns used by the transformer. Their switching occurs due to the movement of the servo drive, which switches the contact, like on a rheostat. The main advantage of these systems is their affordable price. The downside is low reliability and long response time.
How to choose the right one
Now you know,for home. Let's look at how to choose the right devices.
First of all, you need to determine how many devices will work simultaneously. For example, if you are in the kitchen, you turn on the electric kettle, microwave and dishwasher. There is a TV and a computer in the living room, and a washing machine in the bathroom. At the same time, a refrigerator and an individual heating boiler operate in the apartment without turning off - these devices also consume 200-300 watts.
You can find out the power of devices from the passport. But be sure to keep in mind that manufacturers indicate active power, not real power.
Method of mounting the stabilizer after the meter Attention:For correct calculation, you need to know the total power of the installation, and not its operating mode. The refrigerator consumes 100 watts per hour when operating, but when starting, the engine requires 300-500 watts of reactive energy. Therefore, always take the device with a reserve.
For example, the consumption of your apartment is 2000 watts. This is a very realistic figure for a classic “kopeck piece” with modern technology, and not equipped with powerful consumers such as a boiler, electric oven and hob. To account for full power, you need to add 20%. You must also understand that if the network drops by 20 volts, then the transformer loses 20% of its power. As a result, the total reserve will reach 30-40%, and you will need to purchase a stabilizer with a power of 2000 * 0.4 + 2000 = 2800-watt device.
This is all the information you need about voltage stabilizer: what is it? and now you know how it works. It remains to figure out how to connect it correctly. It is recommended to install it immediately behind the meter, before the electrical panel, although you can attach it separately to the required lines. The device must be grounded so that in case of problems it will divert the current and protect your equipment. It is better to invite an experienced electrician to make the connection.
In discussions electrical diagrams The terms “voltage stabilizer” and “current stabilizer” are often used. But what's the difference between them? How do these stabilizers work? Which circuit requires an expensive voltage stabilizer, and where a simple regulator is enough? You will find answers to these questions in this article.
Let's look at a voltage stabilizer using the LM7805 device as an example. Its characteristics indicate: 5V 1.5A. This means it stabilizes the voltage and precisely up to 5V. 1.5A is the maximum current that the stabilizer can conduct. Peak current. That is, it can deliver 3 milliamps, 0.5 amperes, and 1 ampere. As much current as the load requires. But no more than one and a half. This is the main difference between a voltage stabilizer and a current stabilizer.
Types of voltage stabilizers
There are only 2 main types of voltage stabilizers:
- linear
- pulse
Linear voltage stabilizers
For example, microcircuits BANK or , LM1117, LM350.
By the way, KREN is not an abbreviation, as many people think. This is a reduction. A Soviet stabilizer chip similar to the LM7805 was designated KR142EN5A. Well, there is also KR1157EN12V, KR1157EN502, KR1157EN24A and a bunch of others. For brevity, the entire family of microcircuits began to be called “KREN”. KR142EN5A then turns into KREN142.
Soviet stabilizer KR142EN5A. Analogous to LM7805.
Stabilizer LM7805
The most common type. Their disadvantage is that they cannot operate at a voltage lower than the declared output voltage. If the voltage stabilizes at 5 volts, then it needs to be supplied at least one and a half volts more to the input. If we apply less than 6.5 V, then the output voltage will “sag” and we will no longer receive 5 V. Another disadvantage of linear stabilizers is strong heating under load. Actually, this is the principle of their operation - everything above the stabilized voltage simply turns into heat. If we supply 12 V to the input, then 7 V will be spent on heating the case, and 5 will go to the consumer. In this case, the case will heat up so much that without a heatsink the microcircuit will simply burn out. All this leads to another serious drawback - a linear stabilizer should not be used in battery-powered devices. The energy of the batteries will be spent on heating the stabilizer. Pulse stabilizers do not have all these disadvantages.
Switching voltage stabilizers
Switching stabilizers- do not have the disadvantages of linear ones, but are also more expensive. This is no longer just a chip with three pins. They look like a board with parts.
One of the options for the implementation of a pulse stabilizer.
Switching stabilizers There are three types: step-down, step-up and omnivorous. The most interesting ones are omnivores. Regardless of the input voltage, the output will be exactly what we need. An omnivorous pulse generator doesn’t care if the input voltage is lower or higher than required. It automatically switches to the mode of increasing or decreasing the voltage and maintains the set output. If the specifications state that the stabilizer can be supplied with 1 to 15 volts at the input and the output will be stable at 5, then it will be so. In addition, heating pulse stabilizers so insignificant that in most cases it can be neglected. If your circuit will be powered by batteries or placed in a closed case where there is strong heat linear stabilizer unacceptable - use pulse. I use custom switching voltage stabilizers for pennies, which I order from Aliexpress. You can buy it.
Fine. What about the current stabilizer?
I won't discover America if I say that current stabilizer stabilizes the current.
Current stabilizers are also sometimes called LED drivers. Externally, they are similar to pulse voltage stabilizers. Although the stabilizer itself is a small microcircuit, everything else is needed to ensure the correct operating mode. But usually the entire circuit is called a driver at once.
This is what a current stabilizer looks like. Circled in red is the same circuit that is the stabilizer. Everything else on the board is wiring.
So. The driver sets the current. Stable! If it is written that the output current will be 350mA, then it will be exactly 350mA. But the output voltage may vary depending on the voltage required by the consumer. Let's not get into the wilds of theories about that. how it all works. Let's just remember that you don't regulate the voltage, the driver will do everything for you based on the consumer.
Well, why is all this necessary?
Now you know how a voltage stabilizer differs from a current stabilizer and you can navigate their diversity. Perhaps you still don’t understand why these things are needed.
Example: you want to power 3 LEDs from the car's on-board power supply. As you can learn from, for an LED it is important to control the current strength. We use the most common option for connecting LEDs: 3 LEDs and a resistor are connected in series. Supply voltage - 12 volts.
We limit the current to the LEDs with a resistor so that they do not burn out. Let the voltage drop across the LED be 3.4 volts.
After the first LED, 12-3.4 = 8.6 volts remains.
We have enough for now.
On the second, another 3.4 volts will be lost, that is, 8.6-3.4 = 5.2 volts will remain.
And there will be enough for the third LED too.
And after the third there will be 5.2-3.4 = 1.8 volts.
If you want to add a fourth LED, it won’t be enough.
If the supply voltage is raised to 15V, then it will be enough. But then the resistor will also need to be recalculated. A resistor is the simplest current stabilizer (limiter). They are often placed on the same tapes and modules. It has a minus - the lower the voltage, the less current on the LED will be (Ohm’s law, you can’t argue with it). This means that if the input voltage is unstable (this is usually the case in cars), then you first need to stabilize the voltage, and then you can limit the current with a resistor to the required values. If we use a resistor as a current limiter where the voltage is not stable, we need to stabilize the voltage.
It is worth remembering that it makes sense to install resistors only up to a certain current strength. After a certain threshold, the resistors begin to get very hot and you have to install more powerful resistors (why a resistor needs power is described in the article about this device). Heat generation increases, efficiency decreases.
Also called an LED driver. Often, those who are not well versed in this, a voltage stabilizer is simply called an LED driver, and a pulse current stabilizer is called good LED driver. It immediately produces stable voltage and current. And it hardly gets hot. This is what it looks like:
