What to do if there is not enough electricity. Very low line voltage

Often in villages and dachas they talk about poor voltage in the electrical network. This is due not only to their poor technical condition, but also to the purchase of a variety of household appliances that require electricity, which is often in short supply.

At the same time, local power grids are in no hurry to replace equipment with modern, and therefore more advanced, equipment that will withstand increased loads with dignity.

Terristor, a participant in the “House and Dacha” dacha forum, once encountered a problem – the washing machine stopped working. That is, the drum could hardly rotate, and the pump could not lift water from the well.

The 1st Figure shows the normal operation of a step-down transformer.
On the 2nd, the transformer has already been converted and is ready to work to increase the voltage.

He measured the voltage, and the device showed only 180 volts, and this voltage is not enough to operate many household electrical appliances.

But no, there is a silver lining. Once he was reading the magazine “Radio” and an article caught his eye about how to make a step-up transformer using a regular step-down transformer.

And the trick was that if you take, which makes 40 out of 220 volts, and dig deeper into it, then after small changes you can get at the output not a decrease, but an increase in voltage by 40 volts from the network voltage.

By chance, Terristor had such a transformer. And having little knowledge of radio engineering, after 15 minutes he rebuilt it and made a test launch.

Before the test, the voltage was 192 volts, and after, as planned, the voltage increased by 40 volts. This turned out to be an excellent solution in the current situation and despite the lack of voltage, the electrical appliances worked flawlessly.

conclusions

The advantages of this system:

Easy to assemble. For example, if the power of the secondary winding of the transformer is 100 volts, you can safely connect a pump with a power of 500 W.
The device is really cheap.

Disadvantages of this system:

The voltage produced by the device is not automatically regulated, and if suddenly the voltage in the network stabilizes and becomes 220 volts, then at the output you will have 260 volts, a bit too much, but not dangerous if you notice in time.

Terristor himself used this transformer all winter. During this time, he never checked the voltage and not a single electrical appliance was damaged.

In case the voltage in your area changes frequently, you can use a special outlet that turns off electrical appliances that are connected to it if the voltage increases above normal.

Formulas for calculations

You need a transformer with a primary winding of 220 volts. The secondary winding is for the required “missing voltage”. On the secondary winding, the maximum current even for low-power step-down transformers is sufficient.

The calculation can be done using several formulas.

By rice. 1 you can calculate the current of the secondary winding where In – rated load current A; Pn – rated load power (according to the transformer passport) W; Un - rated load supply voltage.

Knowing what voltage needs to be added, the required power of the transformer is determined by rice. 2 where P is the power of the transformer in W, I2 is the rated current of the secondary winding A, U2 is the voltage of the secondary winding, V. Then you need to take a transformer with suitable data - on power and output voltage.

In the last formula you can see that the voltage at the load can be either increased or decreased. To correctly phase the transformer, it is enough to swap the terminals of one of the windings.

It is better to install the transformer in the hallway or in the basement, because the installation is noisy, and from there do the wiring to the necessary electrical appliances.

Posted by a member of the House and Dacha forum Terristor
Editor: Adamov Roman

Often the voltage in the electrical network is 190 volts instead of the stated 220, and sometimes drops even lower. What is the reason for its decline?

Why is undervoltage dangerous?

When the mains voltage is low, electrical appliances will behave differently.

It will emit a symbolic amount of light, a fluorescent lamp will not be able to light up, an LED lamp may or may not light up.

When the voltage drops, the personal computer will start and work, turning off spontaneously from time to time.

The power of the microwave and the performance of the electric stove will drop catastrophically, and the water in the electric kettle will boil later than usual.

A refrigerator or air conditioner with built-in protective modules simply will not start, giving a signal about insufficient voltage.

Household appliances without such protection will be strained to hum their engines, working for wear and tear and will soon fail.

Finding those responsible for voltage sags

First of all, determine whether you are already receiving low voltage or whether it is dropping directly in your home network.

Interview your neighbors, ask what voltage is in their apartment or house.

Yes, the homes of 2/3 of your neighbors will be powered from other phases and their information is unlikely to be useful to you, however, you will get a general idea of the magnitude of the electric voltage in your immediate vicinity.

By turning off the input circuit breaker in the distribution panel, the voltage value at the input.

The permissible deviation from the rated voltage is 10% in both directions, that is, a voltage ranging from 198 to 242 volts is considered normal.

If the electric current voltage at the input is below 198 volts, file a claim with the regional distribution network, energy sales or other company that provides you with electricity supply services.

If the voltage at the input of your meter is within the normal range, then it “sits down” already in your home network.

Turn off all household appliances in the house, turn on the input circuit breaker and measure the voltage in one of the outlets.

When connecting electrical consumers one by one, monitor the voltage change. Once you are sure that the voltage decreases as the load increases, look for the weak link in your home network.

Causes of voltage drop

Reason for low voltage	Remedy
Insufficient cross-section of the main power line cable
A large number of “twists” on the main power line cable	Contacting your energy service company
Overload of a step-down transformer at a substation	Contacting your energy service company
Phase imbalance due to uneven loading of transformer phases	Contacting your energy service company
Insufficient wire cross-section at the input
Poorly executed branch wire from the line to the house	Reconnection to the line in compliance with all requirements
Poor contact in the distribution board, indoor distribution boxes or sockets	Pulling up contacts
Insufficient cable cross-section in the wiring	Replacing the old cable with a new one with a larger cross-section

Ways to privately solve the problem of low voltage

to your input. This should be a device with a decent power reserve and a wide input voltage range.

It will be able to raise the voltage in the network from the critical 140 volts to the nominal 220. Everything will be fine until the neighbors follow your example and acquire the same stabilizers.

The principle of operation of the stabilizer is to increase the output voltage by increasing the input current. Since the power of the transformer at the substation is constant, as the current increases, there will be a voltage drop on the main line.

A dozen of these stabilizers are capable of reducing the voltage to such a value that the source of electricity will turn off due to overload or burn out due to high current.

Another way to protect against power problems is to install uninterruptible power supplies. They are capable of not only stabilizing the voltage in the network, but also serving as a source of backup power in the event of a complete absence of voltage in the network.

Some electricians recommend installing step-up transformers at the input. The advice is effective, but dangerous. Imagine, having set the transformation ratio during the day, increasing the voltage from 170 to 220 volts, you go to bed in the evening.

At night, the voltage in the network returns to the nominal value, but thanks to the transformer, its value in the home network will be close to 300 volts.

There is another technology for stabilizing voltage by installing an additional grounding device at the input.

By grounding the neutral conductor, it is possible to reduce the resistance of both the working zero and the entire power line.

This will indeed make the voltage in the network stable, but if suddenly during repairs on the line the electricians confuse the neutral wire with the phase wire, instead of zero you will have a grounded phase, which will naturally lead to a short circuit with all the ensuing consequences.

If there is a break in the working zero on the power line, all operating currents will flow through your grounding device, which is also fraught with troubles up to and including failure of the grounding.

Let the voltage in your home network always be stable!

The effect of input voltage “sagging” below the established norm is a fairly common problem. It is more typical for power supply in rural areas, but its manifestations can often be observed by city dwellers. It is known that low voltage in the network leads to malfunctions of household appliances, a decrease in their power and premature failure. These reasons are enough not to leave things to chance and take decisive measures to eliminate or reduce voltage surges.

Causes of voltage sag

There are certain requirements for the electrical network, they are given in GOST 13109 97. It states that long-term voltage deviations from the nominal voltage are possible within 10% (-5% and +5%). In addition, short-term voltage surges of up to 20% of the nominal value (from -10% to +10%) are allowed. That is, at a norm of 220 volts, a long-term “sag” to 209.0 V will not be critical, as will a short-term drop to 198.0 V. A voltage drop beyond the specified limits (for example, to 180 Volts) indicates that the network parameters are not meet established standards.

It is important to establish the nature of voltage sags, otherwise eliminating the consequences will be ineffective. Problems with the electrical network may be due to the following reasons:

In the first three cases, it is not possible to eliminate the cause on your own, but you can file a complaint with the energy supply company against the electricity supplier (this will be discussed in detail in another section). Paragraphs 4-6 indicate malfunctions in home electrical networks, so such problems are solved by electricity consumers on their own or by hiring specialists for this purpose.

The influence and consequences of low voltage on electrical appliances

Low voltage affects household electrical appliances as follows:

Based on the foregoing, it can be stated that those devices whose design includes an electric motor or compressor are most susceptible to the harmful effects of low (low) voltage. These include most household power tools, refrigeration units, pumping equipment, etc. The built-in protection of such equipment may not allow the devices to be turned on if the voltage fluctuates or is significantly below normal. Abnormal operating modes reduce equipment resources, which leads to a decrease in service life.

Equipment equipped with switching power supplies with a wide range of input voltages is less susceptible to influence. The “subsidence” is practically not reflected in the heating equipment; the only thing that is observed is a decrease in power compared to normal voltage. The exception is electronically controlled devices.

Ways to solve the problem

It is necessary to start by identifying the reason that led to the “subsidence” of electrical energy. Let us describe in detail the algorithm of actions:

If the voltage is within normal limits without load, but after connecting the internal network it sags, then we can state that the problem is local in nature and will have to be solved on its own. First of all, it is necessary to check the input circuit breaker, since a weak contact at its input or output can cause a voltage “sag”.

As a rule, in cases with poor electrical contact, a lot of heat is generated in the problem area, which leads to deformation of the AB housing. In such cases, it is necessary to replace the protective device. Since there is a high voltage at the input of the device, such work must be performed by a specialist with the 3rd clearance group; replacing it yourself is dangerous to life.

If everything is in order with the AV and no defects are found, you should check the compliance of the cross-section of the input cable. For this purpose, you can use the table shown in Figure 2. If necessary, replace the wire.
In the event that checking the cable and AV does not produce results (the circuit breaker is normal and the cable corresponds to the load), the outlet should be checked. A melted body or sparking when connecting a load indicates unreliable contact, therefore, it is necessary to reconnect.

Please note that all installation work “before the meter” must be carried out by specialists from the service provider (if the contract is concluded directly) or the management company.

Everything is much more complicated when there are external causes. Upgrading the line or transformers at a substation can take years. In such cases, installing a stabilizer will help raise the voltage to an acceptable level.

The voltage stabilizer shown in the figure has an operating range from 90.0 to 270 Volts and is designed for loads up to 10.0 kVA. Devices of this type are installed on the entire house or apartment, that is, there is no need to protect each household appliance separately. The cost of electronic voltage stabilizers is about $200-$300, which is definitely cheaper than buying new equipment to replace broken ones.

You can also raise the voltage to the required level by connecting your home network through a step-up transformer. This method of solving the problem is unsuccessful, since normalizing the electrical system will lead to overvoltage, which, at best, will trigger the protection in household appliances. For the same reason, it is not recommended to use a step-up autotransformer.

Sometimes they try to solve the problem by installing a voltage relay. The effectiveness of this solution is zero; the device simply turns off the power to the network when the voltage goes out of the permissible range. As a result, there is no current in the sockets until the situation returns to normal.

Where to call and complain about the power supply?

Calls cannot solve the current problem; it is necessary to file a claim for inadequate quality of services provided. That is, write a statement to the company providing electricity supplies (if the contract is concluded directly) or file a complaint with the management company. The application must be registered or sent by registered mail (mailing address is indicated in the contract).

If the above measures do not help, you can contact the prosecutor's office, Rospotrebnadzor, the district administration, the public chamber, as well as the district court.

Please note that collective complaints are more effective, so if neighbors or other residents of a house (district, village, etc.) are faced with a low voltage problem, then it is better to involve them in the process.

If, due to voltage deviations from established standards (due to the fault of the service provider), household appliances fail, you can demand compensation for the damage. To do this, you must follow the following algorithm:

You should contact the service provider so that its representatives record that the accident occurred and draw up a corresponding report.
A conclusion is taken from the service center, which indicates the reason for the failure of the household appliance.
A claim is filed with the service provider seeking compensation for damages.
If refused, the issue must be resolved in court.

Low voltage in the electrical network is a very serious problem, which most often occurs with the onset of cold weather. If you are faced with the fact that the voltage in the sockets is 200 Volts or lower, then you need to look for the cause of the malfunction as quickly as possible, since this is fraught not only with incorrect operation of household electrical appliances, but also with their failure. Household appliances with a motor load (refrigerator, freezer, air conditioner, washing machine) are most susceptible to the negative effects of excessively low voltage. In this article we will tell you why there may be low voltage in the network and where to call if this problem occurs.

Main causes of malfunction

First of all, we will briefly consider why the voltage in the network may be below permissible values (according to), and then we will consider what to do in each of the above cases. So, the main reasons for low voltage in a private house or apartment are:

Insufficient cross-section of the input cable branched from the main power line to your home.
Poor contact connection at the location from the power line.
Incorrectly selected cross-section of conductors, busbars for connecting protective devices and branches of wiring lines, unreliable contact of connections in the input distribution board.
Transformer overload at the service substation.
Insufficient cross-section of the main power line.
– the load on each phase of the transformer is uneven (for example, one phase is overloaded, the rest are underloaded).
Unreliable contact or on the supply line. In the event of a violation of the integrity of the contact connection of the neutral conductor of the main power line or its complete break, a significant voltage imbalance will be observed in the network: some consumers will experience excessively high voltage, while others will experience lower than permissible values.

These are the most common causes of very low voltage in the network of private houses and apartments. As you understand, the first 3 reasons apply only to you, and you will have to solve the problem yourself. As for the latter situations, they need to be resolved collectively with neighbors, by writing complaints to the relevant authorities. Next, we will tell you what to do on your own and where to call so that higher authorities can help eliminate the cause of the malfunction.

Ways to solve the problem

In order to list the causes of low voltage in the network, we will also consider ways to troubleshoot the problem.

The first thing you should check is whether there is low voltage in your neighbors or whether low voltage is present only in your area. If it turns out that there are no problems in the neighboring houses (or apartments), we begin to look for a problem in the home electrical wiring.

First, you must turn off the input circuit breaker and measure the voltage value at the input: at the terminals of the circuit breaker where the input power cable is connected. If it is already below the norm at this point (according to GOST 29322-2014 (IEC 60038:2009) ±10% of the nominal - 230 Volts, i.e. 207-253 V), then you need to contact the power supply, as the problem may be in the supply network (reasons - p. 4-7). You can read more about permissible voltage deviations in the article:.

According to what was written above, there can be 3 reasons, if only you have low voltage. Start troubleshooting by checking. If the top terminal has poor contact with the wire, this may well be the cause of low voltage. Visually inspect the body of the machine; if it is melted (as in the photo below), it must be replaced. After this, do not forget to connect the new circuit breaker properly - tighten the wires in the clamps thoroughly.

Also pay attention to the cross-section of conductors and bars used in the distribution panel to connect protective devices and branch wiring lines - it must correspond to the load that flows through one or another section of the electrical circuit.

Is the machine connected correctly and there is no visible damage? Make sure that the cross-section of the input wire is sufficient for the operation of consumers in your house or apartment. We talked about this in the corresponding article. The fact is that if the cross-section of the conductors is insufficient, the voltage drops when an increased load is connected.

If the cross-section of the home wiring cable is sufficient, check how the line is branched from the main line to your input. If this is the case, then we can say with great confidence that the low voltage in the house is due to a poor-quality branch wire. With poor contact, the resistance in the problem area increases, which entails a decrease in voltage. Even if the branch is made with special clamps, inspect them too (the condition of the body). You can also check the clamps by connecting the load - if it starts to spark in this place, or the clamp body starts to heat up, you need to replace the product.

Things get worse if the low voltage in the electrical network is not your fault, but the fault of the electricity supplier. In fact, troubleshooting in this case is quite difficult. Next, we will tell you where to call and complain to solve the problem, and now we will provide a measure that will help increase the voltage in the home electrical network.

You probably know what is best, which can increase the value from 140-160 Volts to the required 220. From personal experience I can say that this is the best option for troubleshooting, because Most often, the voltage is low in the autumn-winter season due to the use of electric heaters. The stabilizer is not that expensive and can protect your household appliances even at high temperatures, which is also very important. If you have the money, we also recommend purchasing an uninterruptible power supply, which can eliminate the problem during a voltage drop, because will supply electricity in autonomous mode. Emergency power systems operate from 140 Volts, which is perfect in our case. The only drawback is the high cost. For a model with a power of 5 kW you will have to pay at least 35 thousand rubles (price for 2019).

Considering the cost of the stabilizer and the fact that at an excessively low voltage (below the operating range of the voltage stabilizer), it can quickly fail, so before purchasing it, it is better to contact the supply organization to solve this problem. Moreover, the reason may be in an emergency situation - a violation of the contact connection of the neutral wire on the main line, and this is fraught with an even greater imbalance of voltage across phases in the event of a complete break of the neutral.

The operation of the stabilizer is shown in the video:

Some experts also recommend dealing with low voltage in the electrical network using transformers or additional grounding, but we advise you to avoid such measures. The fact is that the consequences of such manipulations can be disappointing - overvoltage up to 300 Volts or!

Where to call and complain

When the reason for the low voltage is the insufficient cross-section of the main power line or the weak power of the transformer at the substation, things are worse. Millions of rubles are needed to modernize the substation and power lines, so complaints have no effect, even if they have been written for years. However, you are still required to state that you are dissatisfied with the quality of electricity in order to move the issue of reconstruction forward.

If you don’t know where to call and write a complaint if there is low voltage in the network, we recommend that you familiarize yourself with the following list:

Write a written complaint to the energy supply company.
If no action is taken within 30 days after registering the appeal you wrote, the prosecutor’s office will help you attract energy sales, which we also advise you to contact.
Rosprotrebnadzor.
Administration of the city (district or village).
Energy supervision.
Public Chamber.

We draw your attention to the fact that all these bodies have their own official websites, which are not difficult to find on the Internet. It is not at all necessary to hang around the walls and stand in queues; it is enough to simply write an email to the relevant authority that you have low voltage in the network, and that you have already tried to solve the problem with energy sales. It will be better if you present all available evidence in an email.

Another useful tip is when you write a collective complaint to the energy supply, refer to GOST 29322-2014 (IEC 60038:2009), according to which the deviation from 230 Volts should not exceed 10%.

We hope that now you know what to do when the voltage in the network is low, where and to whom you need to complain so that the fault is fixed! Once again, we draw your attention to the fact that the process of resolving a conflict with energy sales can take a long time, so you need to immediately buy a stabilizer so that all the household appliances in the house do not burn out.

question:
There is very low voltage in my apartment, electrical appliances don’t work, the lamps barely light up, we recently bought an apartment (2 months ago), but we haven’t registered with the BTI*. What to do, where to go, how to resolve this issue faster, before the snow falls.

Very low mains voltage. What to do in case of low voltage

Voltage regulator? Thank you, no need!

Who do you pay for electricity?
Whoever takes the money is responsible for the electricity supply; normal voltage must be demanded from him - the voltage from the meter. The serviceability of the electrical wiring after the meter is usually the concern of the apartment owner himself.
But!

Often, a voltage lower than normal is a fraudulent creative solution by the energy company to its problems - financial and technical:
about electric meters at reduced voltage and Ohm's law for an electric sales company.

Energy sales are not responsible for low voltage in the apartment

Just in case, it’s worth checking and testing the electrical wiring in the apartment for voltage drop: turn off absolutely all electrical loads (you can leave a 100-watt light bulb, you can’t conduct the experiment in the dark) and measure the voltage.
Quite popular about voltage drop is written on Wikipedia: http://en.wikipedia.org/wiki/Voltage_drop

Then turn on the loads at the permissible maximum (the maximum power must be indicated in the electrical design), or look at the current of the fuse (circuit breaker) - the maximum power is equal to the voltage multiplied by the maximum current through the fuse. Or turn on an active load with constant power, for example, an electric kettle of 2-2.5 kilowatts; The wiring should usually be able to withstand this load. The voltage in the network under load will drop by several volts, this is normal.

For example, now I measured the voltage in our house, 223 volts with almost all load devices turned off (2 computers, a 60-watt light bulb, a 13-watt mercury “energy-saving” lamp and computer little things - a switch and a 3G Internet “modem” are turned on). I turned on the 2.4 kW kettle. The voltage in the outlet where the electric kettle is plugged in dropped to 214 volts. This is not fatal, but it is a bit much, because... the kettle is plugged into the furthest socket along the wiring distribution, and the cross-section of the copper wire is 2.5 sq. mm - more correctly, the cross-section of the wire is 4 sq. mm.
(But it’s okay, let’s wait until the house is completely transferred to a 12/24 volt free autonomous power supply - see the Samodom website.)

But if the voltage from the kettle drops by 15-20 volts, this is definitely low voltage, due to incorrect wiring. Usually these are either abnormally thin wires, or strands in metal wires with enormous resistance*, or poor contact somewhere at the connection points.

* - I recently came across one such 15-meter extension carrier, “Made in China” - with a German European certification badge. I cut the cable and saw something terrible - the metal cores of the cable were made of something oxidized, similar to an ancient bronze product, but elastic, like the wire from which delicate metal brushes are made.

An electrician trick I heard about: in some(!) apartments, the electrical wiring is laid not with copper wire, but with aluminum wire of the same cross-section. And aluminum conducts current 60% worse.

In general, if in a new house the light bulb goes out (the voltage drops) when the electric kettle is turned on, you need to shake the normal, according to the project, electrical wiring from the builders.

Undervoltage to electric meter

A typical situation (and not only in Russia) is that residents are moved into a house that is not rented or is not permanently connected to the power grid, and... communications are connected according to construction plans.

If this is the situation, then you need to demand normal voltage from the builders, and if you pay to the electric company, then from the energy company.

The second factor is whether the voltage is constantly low or not. If the voltage in the network is constantly low, then this is how the power network is “configured”, perhaps this is a consequence of phase imbalance in someone’s favor (someone has increased voltage), or maybe the transformer is adjusted in such a way, in favor of someone’s pocket.

If this is a consequence of a “local” phase imbalance, try asking to switch your apartment to another phase, the voltage may be higher there.

And if the electricity sometimes shines brightly, but usually weakly, then this may be a consequence of chronic overload of the electrical network. More precisely, some element (cable, transformer, or substation in general) is simply not able to provide the required power. Perhaps we are talking about tens or hundreds of thousands of dollars "saved" (perhaps in someone's specific pocket) on electrical equipment.
That is, achieve recognition of the problem may mean getting someone into jail, or financial, or criminal trouble. Therefore, for safety reasons, it is better to seek improvement of power supply by a small close-knit group of victims of low voltage.

In any case, take a closer look at how the light bulbs (incandescent!) shine in other entrances, in other apartments. This will help you not to believe in the professional fairy tales of electrical bosses.

Many people advise buying a step-up transformer or an electrical stabilizer. But this is wrong for the following reasons.

1. Many types of electricity meters do not count the actual consumed electrical power, but the consumed current (almost). The lower the voltage, the more current the step-up transformer or voltage stabilizer selects from the network. The more expensive a kilowatt-hour of ACTUALLY consumed electricity is.

2. When the electrical network is overloaded, voltage surges (in percentage, relative) are higher. For example, if the normal voltage is 230 volts, a voltage drop, in the sense of a short-term voltage drop, of 5 volts means little (-2.1%), then in the case of 160 volts it is already 3.1%, that is, almost half more .

And, for example, when the electric motor of a refrigerator starts at low voltage, the light in the apartment may blink not at 5 volts, but at all 10.

An ordinary manually adjustable autotransformer will not increase this voltage dip as a percentage; it will simply produce not 220 volts, but 220 volts minus 3.1% - 212 volts. But an electrical voltage stabilizer may well produce a reverse positive surge after a voltage drop - a short-term overvoltage.

In both cases, this is not good for household electrical appliances. The likelihood of burnout increases!

3. Electronic voltage stabilizers (voltage regulator), as a rule, do not produce a normal sinusoidal voltage at all, but something in the shape of a trapezoid. Many electrical appliances react painfully to such abnormal voltage - they may overheat, internal voltage surges, additional vibrations, etc. may occur. The service life of household appliances may be significantly reduced.

4. For example, they wound a special step-up transformer at the “usual” 150 volts, or a manually regulating autotransformer was set at 150 volts at the input, and then - bam, and there was 240 volts in the network - for example, a fuse in a neighboring house tripped, the load on the quarterly transformer decreased, tension increased. Since the apartment transformer is set to 150 volts (transformation ratio 1.47), then at 240 volts it will output 353 volts into the apartment, which is an absolutely lethal voltage for all household electrical appliances. It’s good if everything burns out without an open flame, and the apartment doesn’t burn down.

And the energy sales company will not pay the victim because 231 volts in a 220 volt network is normal, within the standard. And the fact that they installed a step-up transformer in the apartment is the fault of the electricity consumer. And the fact that the subscriber chronically received 150 volts, and therefore... it is his own fault, why he did not report, etc.

In any case, collect evidence of poor-quality power supply - even witness testimony: such and such saw a dimly lit lamp in the apartment at that time, such and such an electrician measured the voltage in the apartment with a voltmeter or tester (even an uncertified one!).
Believe me, the party guilty of poor-quality power supply will become much more accommodating.

But be prepared for the revenge of the “electricians” - for minor, unprovable electrical dirty tricks.

* - BTI: Bureau of Technical Inventory (BTI) - organizations carrying out state technical accounting and technical inventory of real estate in the USSR, Russia, Ukraine. Currently, BTI operate in Russia in the form of state unitary enterprises and municipal unitary enterprises. In 1918, real estate accounting was transferred to the NKVD of the RSFSR.
(from Wikipedia)
But how does this relate to electricity???