Electrical wiring of an apartment, house It has certain period services. Aluminum wire, which was used in the mass construction of residential buildings from 1950 to 2001, has a service life of 30 years. At the end of its service life, it is necessary to replace the electrical wiring, since, over time, the wire insulation begins to deteriorate, exposing the wires, leading to short circuit. Aluminum becomes very fragile with age; at the slightest bend in the wire, for example when replacing a socket, it instantly breaks, making impossible installation sockets Also, due to strong oxidation, the resistance at the junctions of the wires increases many times, this leads to strong heating of the wires and can lead to spontaneous combustion of the electrical wiring and, possibly, to a fire in the room.

Toward reduction service life of electrical wiring leads to excess of the design load. In the 50-80s of the last century, the maximum load in an apartment was considered to be a current of approximately 10-12 Amperes, and this is achieved by turning on electrical network modern kettle with a power of 2500 watts. The load can be easily calculated using the formula: A=W:V (A - Amperes, W - Watts, V - Volts), 2500W: 220V = 11.36A. From this example it follows that when only one vacuum cleaner is plugged into a power outlet, almost the maximum permissible load to an electric wire.

Over the past 20 years, there have been tens of times more appliances in everyday life, and almost each one requires its own socket, grounding, additional line, and protective device. In order for all your devices to work properly, you must have electrical wiring in your apartment that complies with all modern standards and regulations. Such electrical wiring can only be in a new house, and even the number of sockets and their location may not match your interior.

But what about those who live in old Khrushchev-era buildings, nine-story panel buildings built in the 70s and 80s, in which there is only one outlet in the kitchen?

The most ideal moment for replacement of electrical wiring counts major renovation apartments, when you can safely hollow out all the walls, lay new wires and make repairs and live in peace. But it happens that for some reason you don’t want to do renovations in your apartment, or it’s simply unrealistic due to your accommodation big family, children, pets or just fear of a heap of dust, garbage...

Which is better - copper or aluminum wiring? This question is often raised among specialists and ordinary people who are planning to change old wires in a house, apartment or office. But to accept correct solution, it is important to know the advantages and disadvantages, operating rules, as well as the main differences between copper and aluminum switching.

Advantages and disadvantages

Aluminum wiring has the following advantages:

• Small mass. This feature is important when installing power lines, the length of which can reach tens or even hundreds of kilometers.
• Affordability. When choosing a material for wiring, many are guided by the cost of the metal. Aluminum has a correspondingly smaller value, which explains more low price products made from this metal.
• Resistance to oxidative processes (relevant in the absence of contact with open air).
• Availability protective film. During operation, a thin coating forms on aluminum wiring, protecting the metal from oxidative processes.

Aluminum also has a number of disadvantages that you need to be aware of:

• High metal resistivity and tendency to heat. For this reason, the use of wires smaller than 16 sq. mm is not allowed (taking into account the requirements of the PUE, 7th edition).
• Loosening of contact connections due to frequent heating when passing a heavy load and subsequent cooling.
• The film that appears on an aluminum wire upon contact with air has poor current conductivity, which creates additional problems at the junction points of cable products.
• Fragility. Aluminum wires break easily, which is especially important when the metal frequently overheats. In practice, the service life of aluminum wiring does not exceed 30 years, after which it must be replaced.

Rules for connecting copper and aluminum

There are situations when you need to replace only part of the wiring or add (move) several outlets in the apartment. In such a situation, the question arises. To avoid increased heating in places where copper and aluminum wiring are combined, it is worth using the following switching methods:

The considered connection methods can be used to combine wires made of various metals (not only copper and aluminum). This performance guarantees high level safety and the ability to avoid potentially dangerous twisting. But it is worth remembering the importance of periodically checking and tightening bolted connections and terminal blocks, because they tend to loosen.

Which wiring material is best?

Now let's look in more detail which wire is better, copper or aluminum. In this regard, many stereotypes and misconceptions have appeared, which we will discuss below:

• Durability. It is believed that the lifespan of copper wire is longer than aluminum. This is a misconception. If you look at a special reference book, you can make sure that the service life of cables made of both types of metal is identical. For products with single insulation it is 15 years, and for products with double insulation - 30.
• Tendency to oxidation. When using an aluminum cable, it is worth remembering its tendency to oxidative processes. Back in school, we were told that Al (aluminum) is a metal that actively interacts with oxygen, which is why a thin film appears on its surface. The latter protects the metal from further decay, but impairs its conductivity. If you isolate the wire from environment, the risk of oxidative processes is minimized. The best option- use of special terminal blocks with conductive paste. The peculiarity of the latter is to improve the quality of the contact connection between two wires and remove the oxide film from the metal. In addition, a special lubricant prevents aluminum from coming into contact with the surrounding air.
• Strength. Copper wiring considered more durable and able to withstand repeated bending. GOST states that a wire made of copper must withstand 80 kinks, and one made of aluminum - 12. If the wiring runs in the wall, floor, or is hidden under the ceiling, this feature is not so important.
• Price. The price of aluminum wire is 3-4 times lower. But when choosing, it is important to remember that a copper wire with a cross-section of 2.5 sq. mm is designed for a current of 27 Amperes. If you give preference to aluminum wiring, the thickness of the wire should be 4 square meters. mm (rated current 28 Amps).
• Resistance. When deciding whether to choose aluminum or copper wires, it is worth considering different resistivities. For copper, this parameter is about 0.018 Ohm*sq.mm/m, and for aluminum - 0.028. But it is worth considering that the total resistance (R) of the conductor depends not only on the mentioned parameter, but also on the length and area of ​​the conductor. If we take into account that aluminum wires of a larger cross-section are used for the same load, the final R of copper and aluminum products will be approximately identical. The greatest resistance occurs at the joints, but if you follow the tips discussed above, you don’t have to worry about this.
• Ease of installation. It is believed that the connection of aluminum wires is more difficult task. This is only relevant for the usual connection of wiring, by twisting. In the case of using end caps, terminal blocks or bolts, this problem disappears.

The situation that implies deserves special attention. When copper and aluminum combine at the point of contact, various processes occur, due to which the resistance increases. As a result, the junction of the two wires overheats, the insulation is destroyed and the risk of fire increases.

The feature discussed above is characteristic of all metals having different resistivities. In addition, many manufacturers do not use “pure” metals, but their alloys, which also leads to a change in the resistance parameter. To avoid problems in the future, it is better to connect the wires correctly and avoid twisting them.

In conclusion, here are a few tips that should be taken into account when organizing wiring:

1. When independent design wiring in a house or apartment, it is better to choose copper wires. With a smaller cross-section, they can withstand greater currents and are more resistant to frequent bending. No less important point- volume. Copper wires are compact, which simplifies the process of creating grooves. For example, when connecting a receiver with a power of 7-8 kW, the aluminum wire should have a cross-section of about 8 mm. The cable has three cores plus a braid. As a result, the total diameter is about 1.5 centimeters. For comparison, copper can have a cross-section of 4 sq. mm, and the overall diameter is no more than a centimeter.
2. When installing a socket, a three-core cable with a ground wire must be used. The distance of the socket from the floor is 30 cm. When organizing a lighting circuit, it is allowed to use cables with two cores (grounding is not needed here).
3. It is forbidden to hang the entire load on one pair of wires (especially if they are aluminum). The best option is to divide the circuit into several lines. For example, a bathroom is powered through one machine, lighting through another, a kitchen through a third, and so on. The wire cross-section for the kitchen and bathroom should be 4 or 6 sq. mm, and for the lighting circuit - 1.5 or 2.5 mm.

The most difficult situation is in old apartments where aluminum wires are installed, which have outlived their useful life and require replacement. Wiring with a cross-section of 2.5 sq. mm can withstand a load of no more than 20 Amps, which is not enough for modern electrical receivers. In addition, the insulation of the wires loses its elasticity over time and gradually deteriorates. In such a situation, the only solution is to completely replace the wiring with copper wires.

Read more why it is worth replacing aluminum wiring on copper in an old house, watch in this video:

Results

Which wire is better? From a performance standpoint, copper is more preferable. Based on cost, aluminum wires are cheaper. And here it is important to make a decision - to save on your safety or not.

At the moment, almost every owner of an apartment or private house has encountered the problem of replacing electrical wiring. There are a huge number of situations that can affect the replacement of wiring. Aluminum wiring is also considered common and therefore in this article we decided to consider it.

In this article, you can learn all the pros and cons that can affect the use of wiring.

Aluminum wiring and its advantages

First, you need to remember that aluminum wiring is not considered durable or of high quality. Nevertheless, this type of wiring is carried out in most apartments or private houses. The main advantages of this product include:

1. Ease. Compared to other types of wires, it is significantly lighter.
2. Corrosion resistance. Aluminum is significantly less exposed to this effect than other types of metal.

When using it, you also need to remember that the rules prohibit the installation of aluminum wiring with a cross-section of less than 16 mm. When oxidized, this indicator becomes oxidized and this can most likely be attributed to a disadvantage.

Recently, aluminum wiring has been used most often in extensive power cables. This is due to the fact that the product will be light in weight. Also in this case you can get significant savings. Typically, aluminum is used in SIP cable. For air laying it can be considered the most optimal and suitable. This type of wiring has not been used in new buildings for a long time and this is due to a number of factors.

Main disadvantages

The main disadvantages for many electricians include:

1. Fluidity of the material. In the case of a screw connection, the wires may stretch and the connection will be unreliable.
2. Aluminum fragility. During long-term use, the wires may simply break.

Important facts

If you are planning to use it in your home, then you should know the dangers of aluminum wiring. The main factors include:

1. International standards indicate that aluminum wires can be considered the most fire hazardous.
2. Cases of death due to its fire appear regularly.
3. In houses where aluminum wiring was installed, dangerous situations occurred 55 times more often.
4. This type of wiring is only available on a temporary basis.
5. Connecting copper and aluminum wiring is strictly prohibited.

It is these factors that can affect the fire of wiring in the house. In the video below you can see how dangerous this type of electrical wiring is in your home.

It is important to know! It is not recommended to use such wiring at home. It is especially prohibited to use aluminum wires when laying.

Is it worth changing the wiring?

If this wiring was installed in your home, then it urgently needs to be replaced. At the moment, the main disadvantage can be considered the load that it can withstand. IN modern world it will not withstand the load created by household appliances. A large cross section in this case will not solve this problem.

Many people want to make a replacement, but in most cases you can encounter certain difficulties. The main problem is the cost of wires. You may also need to drill through all the walls in your home while doing the replacement. If necessary, in order to completely unload your system, you can make several lines from aluminum. They are the ones who will take on the entire load. If you don’t want to spoil your interior, then the new wires can be hidden in the baseboard. Thanks to this, you can easily reduce the load on aluminum wiring.

If you cannot complete these tasks yourself, then you will need to call a specialist who will do everything himself for a certain amount. In most cases, the problem can appear at the very beginning. Installation may require an electrician's tool. If it is not there, then the purchase will cost a lot of money. Partial replacement of electrical wiring will help solve these problems.

Operating requirements

If you decide to use aluminum wiring in an apartment or private house, then try to take into account the following requirements:

1. The cross section should be 16 sq.mm.
2. During work, you need to use clamp contacts. They will ensure a reliable cross-section of wires.
3. During installation, use welding of aluminum electrical wires in junction boxes. If you cannot complete this process yourself, then you should use the services of specialists.

Below we have presented to your attention a table that will indicate the maximum loads on aluminum wires.

During installation, also try to take into account all the rules fire safety. We already have an article that will help you comply with fire safety regulations. Below you can also watch a video that will tell you the features of aluminum wiring.

This is all the information we wanted to bring to your attention about the pros and cons of aluminum wiring in a private house or apartment.

First of all this fire hazard. Secondly, it is a danger to life and health (current up to 36 volts is considered safe for humans). And thirdly, poor outdated electrical wiring means unstable operation and failure of equipment, breakdown of expensive household and lighting fixtures.

How to realize that there is old wiring in the house?

First of all, you need to pay attention to the electrical panel. Typically, this is where the electricity meter is installed. If there are still old Soviet plugs in the panel, then you have old wiring! Everything is obvious here - the wiring in the house is rotten, with aluminum wires. The second, important sign of old electrical wiring is if you are periodically shocked in the most unexpected places. Don't wait until next time - call an electrician immediately! And if possible, be sure to replace all traffic jams with automatic ones. Don't wait until they burn out next time. It is best to entrust the replacement of traffic jams to automatic machines to a professional, - call an electrician for 1 hour and the job is done! Remember! That untimely replacement can cost you significantly more.

“Fireproof” wooden panel with melting wires

What are the dangers of aluminum wiring?

The lifespan of aluminum wires is significantly less than that of copper wires. Aluminum is more susceptible to oxidation and is a less flexible and softer metal (compared to copper alloys). The problem with aluminum is especially pronounced in places of connections and kinks in the wiring. High humidity and poor contact also accelerate oxidation processes. Subsequently, this leads to overheating and burnout of the contact.

Aluminum wiring

Old aluminum wiring has single insulation, which is simply unacceptable according to modern rules! Single insulation is fraught with current leakage into walls or other structures of the house. IN modern home, you just need a double insulated wire, which is called a cable. According to the new rules, only cable is allowed to be used in apartments and houses.

This is how current passes through a person

Another disadvantage old wiring, is the absence of a third, so-called "safe" wire, known as the ground wire. In old five-story buildings, Khrushchev, Stalin, and panel houses, up to the construction of the early 2000s. — The grounding wire was simply not provided! Therefore, installing sockets with grounding, without replacing all the wires, does not make any practical sense. In special, ridiculous cases, this can even play a cruel joke if done incorrectly. installation of sockets! New rules require grounding all electrical equipment, and accordingly the presence of a safe wire in all electrical wiring. What is the term grounding and why it is needed can be read.

Solder boxes and twists

Standard location of junction boxes

Probably everyone has heard the concept of twists. In old electrical wiring, twists are normal. A good twist is no worse than, for example, a bolt clamp. The main thing and necessary condition, - all twists and connections of wires must be located in junction boxes, which serve as a place for safe switching (connection) of wires. According to the rules, it is not allowed to block access to junction boxes, cover them up or cover them with wallpaper. Typically, junction boxes with twists are located above the light switches under the ceiling.

Old twisted wires

Twisted aluminum wires in these places become unusable over time, especially when high humidity and poor quality installation. Signs of problems in the junction box are: blinking lights, electrical crackling under the ceiling, burning smells (not always obvious), or a partial absence of light in the apartment. In such cases, it is necessary to look for and open old junction boxes in order to sort through (reconnect). To do this, they unravel the old strands and place the wires on special terminal blocks, having previously treated the ends of the wires.

Terminal blocks for connecting wires

A fairly common (even too common) and unpleasant problem is the twisting of copper wires with aluminum ones. The fact that you can’t do this should probably be taught in school! And not many people know that this is one of the main causes of fire! Thin wires with a cross-section that does not correspond to the load are the second factor causing fires! Any wire that passes current through itself heats up, and it heats up in direct proportion to the load. That is, any wire can be heated like a soldering iron - just apply a good load to it! If you see that, for example, a household heater is hanging on thin wires, turn it off and immediately call an electrician, - Old electrical wiring is the most common cause of fire!!! .

Twisting - you can’t do that!

The dangers of old sockets and switches

Old electrical installation products: sockets and switches do not meet modern electrical safety standards. It is simply impossible to insert a plug into an old Soviet-style socket without additional effort, and when you try to insert it with a blow, the socket usually breaks.

The main problems in old wiring most often appear in feed-through sockets. Pass-through sockets are called sockets through which electricity flows from the source (another socket) further to the next socket or consumer. Usually, where the wires are connected in the socket, a break occurs. And the worse the contact, the higher the load on the connection point. At higher currents, overheating and even fire are possible. One outlet can carry the entire load in the apartment, and if the outlet is old and constantly in use, there is a high probability of the contact weakening in it.

It is clear why most often it is the old sockets that fail. In the best case, some of the sockets in the house stop working, but if things go wrong, they simply burn and melt. And the saddest thing is that no machine other than an RCD can save you from this.

In general, pass-through sockets are normal, and they are allowed by the rules. Not a single modern wiring can do without them. This is primarily due to the enormous cable savings. High-quality and correctly installed pass-through sockets cope with their task with a bang. The main thing is not to exceed design loads on the line with sockets.

The same, but not fully, applies to light switches. Of course, the load on switches is much less than on sockets, but they can also burn like the sockets in the photo. By the way, the switches are on a string, this is another sign of awareness that something is wrong with the wiring. The socket in the old socket box is supported by pieces of wood

Lighting. How do you know when it’s time to change everything?

It is necessary to pay attention to lighting fixtures: old chandeliers, sconces, lamps. The weak point of old lighting devices is the cartridges! Over time, the plastic of the cartridges dries out and bursts, the contacts overheat and oxidize, hence all the ensuing problems. Often, due to such sockets, light bulbs explode, or the base is left inside the socket. Replacing sockets in old chandeliers is not a cheap pleasure, as it is a very painstaking job and requires quite a lot of time. It is much easier and cheaper to buy a new lighting fixture.

Be careful with electric shock! Don't have the funds to completely replace the wiring? - Do it at least partially! Any improvement in wiring is a huge plus, which significantly reduces the likelihood of any problems with wiring and will significantly reduce energy costs.

Old pre-war wiring in a dilapidated house on Old Arbat.
Exclusive photo from our electrician

If you have questions or need professional electricians, write or call +7 495 760 36 77 !

I think all owners of apartments and houses sooner or later are faced with the question of replacing electrical wiring, its rational use, advantages, disadvantages, service life, and so on. Today we will try to explain to our readers as easily and clearly as possible all the pros and cons of using aluminum wiring, and we will also figure out whether it is worth changing it to copper or not.

Advantages

From the very beginning, it should be noted that aluminum wiring is not the most reliable and high-quality and cannot boast of any outstanding merits compared to other types. But, nevertheless, it is precisely this type of electrical wiring that is installed in most old houses and apartments (Khrushchev). So, let’s start with the advantages of this type:

• lightness (aluminum has less weight compared to other metals that are used in electricity as conductors);
• resistance to corrosion (metal when exposed to air instantly oxidizes, forming a film that protects the rest of the wire from further corrosion).

Please note that the Electrical Installation Rules (EPI) prohibit the use of aluminum wires and cables with a cross-section of less than 16 square meters. millimeters. And during oxidation, this indicator decreases significantly and the area of ​​the cable conducting current, in turn, also decreases. However, this should rather be considered a disadvantage.

Today, aluminum in electrical wiring is used most often in extensive power cables, where the weight and cost of the material are very important factors. Savings in in this case can be very weighty - aluminum is a cheap metal - and the amount of material used will still allow you to spend less compared to other types of wires. A true example of this is the enormous popularity of the wire, the cores of which are made of aluminum. For aerial cable laying, this conductor is one of the most suitable. However, aluminum wiring has not been used in new buildings for a long time, and there are reasons for this.

Flaws

There are quite a few disadvantages to this type of wire:

• fluidity of the metal (aluminum tends to stretch, this has a negative consequence in the case of screw connections of wires);
• fragility of aluminum (in the process of aging and a long service life, the wires will simply break, especially with frequent loads and overheating).

All of these shortcomings, to one degree or another, ultimately lead to the fragility of the entire power supply system and a short service life. When asked how long aluminum electrical wiring lasts, you will receive a comprehensive answer - a service life of up to 25 years.

A few important facts

So, to let you know why aluminum wiring is dangerous, we recommend that you familiarize yourself with the following facts:

1. In accordance with international standards, aluminum electrical wiring has long been recognized as a potential fire hazard.
2. Cases that have caused death have been recorded more than once.
3. In houses and apartments where an aluminum electrical network was used, fire cases were recorded 55 times more than with other electrical wiring.
4. This type of wiring is still permitted, but only on a temporary basis.
5. To prevent fire, do not connect copper and aluminum wiring together.

All these factors can cause a fire in the home network and, as a result, a fire in a house or apartment. You can clearly see how dangerous this type of electrical wiring is in the video below:

Example of a dangerous situation

Is it worth replacing the old wiring?

The answer to this question is unequivocal – Yes! One of the nuances that speak in favor of replacing aluminum wiring is the maximum load that it can withstand. Even 100% functional wiring that was used before will not withstand the loads in the modern world. And installing more powerful electrical wiring (with a larger cross-section) is prohibited, as this can lead to a fire.

Copper cable can withstand modern loads, is more reliable and fire resistant. Therefore, replacing aluminum wiring is certainly worthwhile. Especially if you choose the best option.

Another point that complicates the process may be the financial side of the issue. or an apartment can cost a pretty penny. Also for complete replacement old wiring will need to be re-drilled into all living areas. If you are not a “jack of all trades” and cannot cope with the task yourself, in this case there is a way out - you can make a couple of separate lines with a copper cable so that they take on the main load of the electrical network, and use the remaining aluminum lines only for lighting. In addition, new wires can be hidden under the baseboard or in the door jambs. This way you will reduce the load on aluminum wiring and make it safer and more reliable.

If you take on this labor-intensive process yourself, get ready for considerable expenses. Firstly, it is necessary. It’s good if you have one or your friends/relatives have one. Otherwise, it’s a waste again. Secondly, set aside time for this. In the modern world, even this can be difficult. And thirdly, be prepared for the fact that you may spend less time renovating than cleaning up after it.

But there are still life situations when complete or partial replacement of electrical wiring is impossible. In this case, you need to know the most important rules for using aluminum wiring.

Basic operating requirements

If you nevertheless decide to use aluminum wiring in an apartment or private house, consider the following requirements:

1. Cross section of at least 16 square meters. mm (we already talked about this, but it wouldn’t hurt to remind you).
2. Use clamp contacts (as well as a special lubricant that will prevent oxidation of the contacts and preserve low level transition resistance).
3. Use welding of aluminum electrical wires in junction boxes (requires a large investment of time and money, so it is rarely used). If you do not carry out the work yourself, monitor the work of electricians in your home and monitor the process to ensure that all technical aspects are adhered to.

It will also be useful for you to know the maximum load on aluminum wires of different sections. We provided all the data in the table:

And remember, regardless of the type of wiring in your home, adhere to fire and electrical safety rules, as well as operating rules. This way you can protect your family and your home from unwanted consequences and accidents. Finally, we recommend watching another useful video