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I brought in an electrician to update the electrical input to the house.
He began to insist that the connection to the house should be made only with copper wire,
proving that this is a mandatory requirement.
I have refused his services for now.
Tell me, is his requirement mandatory?
And one more thing: which wire is better: copper or aluminum?
Vistr
Such a mandatory change requirement aluminum wires for copper ones, but nowhere to be found yet.
There are only recommendations.
Most likely, this is a personal initiative of the electrician himself. Because copper wires are much more expensive
aluminum Probably, the electrician could have some kind of personal benefit.
Now about which wire is better: copper or aluminum...
Copper according to its electrical characteristics better than aluminum, i.e. her resistance is almost
one and a half times less than aluminum.
In other words: with the same wire diameter, a copper wire can transmit one and a half
times more current without heating up.
But what difference does it make to you if you use aluminum wire of a slightly larger cross-section?
In addition, copper has a very bad quality: it oxidizes strongly over time.
Therefore, the reliability of contacts quickly decreases. This will cause the wire to heat up around
contact node. Accordingly, the insulation begins to melt and a short circuit may occur.
If you still decide to use copper wires, then their ends must be well stripped
and earn money. You also need to look at all the fastening elements of the contacts.
It is desirable that they be either brass or bronze.
liquerr
Today, professionals prefer copper. Why? In open air, aluminum quickly oxidizes, forming an oxide film that practically does not conduct electric current. Aluminum is a fragile, flexible material - bent several times and it broke. With prolonged use, it literally crumbles into powder. Copper also oxidizes, but its oxide is conductive. it does not lose its electrically conductive properties. Resistant to torsion, bending, etc. Yes, it is more expensive.
But there is no point in saving money here - remember, the miser pays twice!
Vlad128
The electrician is right. Direct connection of copper (brass) parts with aluminum causes rapid destruction of the latter due to contact corrosion. Therefore, in old plugs, sockets and switches, the contacts for the aluminum wire were made of galvanized iron. Nowadays, such electrical products are practically not used. There is only one option left: a cable with a copper core.
Oleg40
My aluminum wiring has served for 30 years without any complaints, and even despite the repairs, I have not replaced it with copper. The only downside is its fragility. During this period of time, I had to change switches and sockets a couple of times. The wire sometimes broke, but since there was a reserve left in the box, this is not a problem. It's more likely fashion trend This and some advantages in installation. If you install aluminum, it won’t be a big problem; it’s more important not to make a mistake with the cross-section.
jack
In fact, there are rules and regulations that must be followed. Input into the house is regulated by the PUE, Chapter 2.1 tells us about the input and wiring in houses, Chapter 2.4 - there is about overhead lines and inputs into the house, Table 2.4.2 - here are the standards for cables and their cross-sections that can be used for input, for aluminum has its own standards for copper, and much also depends on the distance from the support to the house.
vladislavus
Copper actually has less resistance than aluminum and can withstand heavy loads well. Aluminum is a more fragile material and I myself “burned” on this.
All wiring in Soviet-built houses is made of aluminum wires. Then this was completely justified, because the load on the networks was much less. Therefore, during the repair process, the question often arises: Is it possible to connect these two wires with ordinary twisting?
When answering the question about the possibility of connecting aluminum and copper wires using conventional twisting, you can confidently answer “no” and here’s why.
Aluminum and copper are not galvanically compatible. With them direct contact when passing electric current a chemical reaction begins under the influence of water vapor, always present in the atmosphere. And a so-called galvanic bath is formed, which leads to an increase in resistance between the wires and, as a result, to corrosion. As a result, the twist will begin to heat up, and in the future may lead to a fire.
This is perhaps the most main reason on which twisting of aluminum and copper wires is not permissible. But there are also factors that negatively affect this type wire connections. 
Aluminum and copper have different coefficients of expansion when heated. When operating under or without load, the wires will expand and contract differently, causing their connections to become loose over time. And this is again overheating and a possible cause of fire. 
Another negative factor is the oxidation of aluminum. Over time, the surface of aluminum becomes covered with an oxide film with a low conductivity coefficient. In this case, a large resistance arises, which leads to weakening of the contact and heating. And there it’s not far from the fire.
Having examined in detail all the reasons for the ban on direct twisting of aluminum and copper wires, it is obvious that it is not worth risking your home. But this does not mean that there are no ways to connect these wires to each other. Now there are special adapters with which you can make a reliable and safe connection.
The simplest and most convenient way to connect aluminum and copper wires, in my opinion, are self-clamping terminals. 
The connection and disconnection of the wire is carried out using a special lever. To secure the wire, you just need to lift the lever and insert the cleaned wire into the vacated hole. Then lower the lever back, thereby fixing the wire in the terminal. The speed of installation and reusability are excellent characteristics that make you choose them.
But this is far from the only way to safely connect aluminum and copper wires; there are others.
Electrical cables differ in the type of insulation, cross-sectional diameter, material of conductive cores, area of application and operating conditions. Copper wire is widely used to transmit electricity.
Copper cable: what it consists of and what are the advantages
The working element of the cable is a conductor made of electrical copper. Inside the cable there are several insulated cores enclosed in a common inner sheath. Depending on the operating conditions, the product is additionally coated protective screen or armor.
Advantages:
High thermal and electrical conductivity. This means that for solving electrical installation problems, you can choose a copper cable with a smaller cross-sectional diameter than a cable with an aluminum core. Losses when heating the conductor will be less. The property of the cable remains unchanged even when the metal oxidizes.
Plasticity and flexibility. Copper cable is resistant to bending and twisting, which makes installation and further operation easier.
Resistance to corrosion and, as a result, long service life. Complete replacement of wiring requires a major overhaul. If you choose a copper cable, then in the next 30-35 years you don’t have to worry about replacing it.
Minimal risk of wire fire. In case of fire, combustion does not spread, but insulating material emits a minimum of smoke and gas.
Applications of copper cables
Cables with a copper core are used in power lines, which serve to transfer and distribute electricity in stationary installations. The use of copper cables is justified in industrial enterprises where there is a risk of fire or explosion. With their help, they install internal wiring in residential and office premises, industrial complexes, industrial and public buildings.
Main types of copper cable
1. Power. They are used to transmit electricity from power plants to substations, utility and transport facilities, and industrial enterprises. Power cable insulation can be rubber, plastic or paper. Inside there are up to 5 conductive wires. In armored copper cable, the covering is made of aluminum or lead. The purpose of the cable can be distinguished by the marking elements.
VVG, VVGE without marks - the cable is used for laying single lines indoors and in cable installations.
Marking ng-LS (does not propagate combustion, low degree gas and smoke emissions) - high level fire safety allows the use of copper power cables of this type in concert halls, stadiums, and metro buildings. Installation in soil is permitted and can be used at nuclear power plants.
Marking ng-FRLS (fire-resistant, flame retardant, low degree of smoke and gas emission) - power cable with copper wires Suitable for power supply of fire alarms and pumps, evacuation elevators, lights on emergency exits and escape routes. In the event of a fire, cables of this type continue to conduct current for 2-3 hours. Mark (a) - the cable does not propagate fire in a group installation due to the use of insulating materials with a reduced degree of flammability.
2. Controls. Used for connection electrical appliances, distribution devices and mechanisms. A control cable with copper conductors is installed in tunnels and channels if protection against mechanical damage is provided. Possible installation outdoors and indoors.
3. Household. May contain one or more copper wires. Single-core types are used to connect welding machines. The multicore type of cable is used to make outdoor carriers.
4. Special (signal cables). They are used to transmit signals (high-frequency cables for long-distance communication, low-frequency cables for local communication).
Features of operation
Power products of the VVG brand and their modifications are in demand among installers. This type of wire is characterized by double PVC insulation. Permissible load per cable ranges from 60 V to 600 V (depending on the cross-section diameter).
The flexible copper cable (control) is insulated with a layer of rubber. It can even be used when laying power lines for construction sites in harsh climatic conditions. To improve performance, special components are added to the cable insulating material.
For installation in tunnels, routes, in the air and in the ground, it is recommended to choose an armored cable with double insulation. The outer coating includes graphite chips, which maximizes the cable's resistance to fire and mechanical damage.
MTD "Energoregionkomplekt" is the official dealer of the Energokabel plant and offers high-quality products for sale cable products from the enterprise. From us you can buy copper cable, power wires, lighting cords and wires, as well as other types of products that meet Russian norms and quality standards.
It is impossible to build a home electrical network without an electrical cable. However, to furnish your home, it is not enough to install it correctly; you also need to correctly select the appropriate type. And for this you need to know what characteristics influence the choice. Do you agree?
We will tell you what types of products it offers modern market and what wire to use for wiring in the house. We will introduce you to the popular nomenclature and help you understand the labeling of products for laying power lines. Let us indicate what buyers and independent electricians should focus on.
In order to optimize perception, we supplemented the information presented for review with diagrams, photo selections, and video recommendations.
The main elements of any electrical cable are the cores - elements for the passage of electric current, isolated from each other by an internal sheath and enclosed in a common sheath.
They are designated by the abbreviation TPG.
In addition to current-carrying cores (1), the cable may contain such structural elements as core (3), wire or steel armor (2) and outer sheath (4)
There are two types of conductors for transmitting electrical energy:
- single-wire solid;
- stranded, consisting of large quantity thin threads.
Some people mistakenly believe that single-wire conductors and single-core cables are an identical concept. In fact, single-core products can have only one core, which, in turn, can be made of single or multi-wire.
The basis for the manufacture of current-carrying conductors can be copper or aluminum. If we compare these metals, then aluminum, although it is cheaper, loses in that it has a lower level of electrical conductivity.
This means that with an equal cross-section, a copper conductor is capable of passing more current. The only “minus” of copper is that it cannot be directly combined with other metals. Those. To connect to aluminum, you will need an adapter that eliminates the formation of a galvanic couple.
Aluminum - no the best option for wiring in the house, since it has a low level of electrical conductivity, and during operation it oxidizes faster and breaks at bends
If the connection is made by twisting, then this place will quickly oxidize, which will lead to a break in the contacts, which may result in a short circuit in the line. Ideally, you should choose the same type of wire for all lines in the apartment.
Cables for electrical signals equipped with a common protective shell.
The insulating layer can be made of:
- rubber;
- polyethylene;
- PVC plastic.
Each of these materials is characterized by high insulation characteristics. Thanks to this, they can be used in networks of various voltage classes within 500 W.
The main purpose of the outer braid is to protect conductors from moisture, which can lead to damage to the integrity of the insulation and, as a result, to clouding of optical fibers
Any cable used for indoor and outdoor cables has at least two insulating layers: the first protects the internal cores collected in a bundle, the second encircles only one core.
Types of electrical wires
There are several classifications that masters focus on when choosing.
The first sign by which cables are divided is number of cores. The operational parameters of single- and multi-core products are detailed in the table below.
Summary table of operational parameters of single- and multi-core electrical products depending on the number of threads involved. The difference exists both in the device and in purpose
Below are the four most popular types of cables used in installing indoor wiring.
Type #1 - VVG cable
When arranging indoor electrical wiring, which involves using VVG cable. It is used to transmit electric current at an operating voltage within 1000 V. The number of cores in such products can vary from one to five.
The VVG current conductor is produced in one of four versions: in the form of products with a flat or round cross-section, or triangular or square
Among the undeniable advantages of VVG products is a wide operating temperature range. It can be safely used at temperatures from -50 °C to +50 °C. The wire is famous for its high tensile strength and ability to withstand humidity up to 98%.
A product of this type can have one of three designations:
- « P" - indicates flat type sections;
- « h» - means that a rubber compound or PVC bundles are located between the TPG insulation and the outer braid;
- « ng» - indicates that the insulation does not propagate fire.
In any cables of the VVG variety, with the exception of those designated “z,” the space between the outer sheath and the insulating layer of the cores is not filled.
The outer sheath of the VVG cable is usually painted black, the internal insulation of the current-carrying conductors is marked with yellow-green, blue, red or white colors with a blue stripe
For domestic needs, a cable with a cross-section of 1.5 mm 2 is used; when arranging a private home, a product with a cross-section of 6 mm 2 is used. The bending radius of the product is determined by multiplying the smaller cross-section by 10.
View #2 - NYM cable
NYM– another high-quality power cable designed for conducting power and lighting networks with voltages up to 660V. The multi-wire conductors of the product are made of copper.
The number of conductive cores of an NYM cable can vary from one to five. The minimum parameters of the cross sections of the products presented for sale are 1.5 mm 2, the maximum is 16 mm 2.
The bending radius corresponds to four cross-sectional diameters.
NYM cable in section: copper conductors are enclosed in a PVC sheath, between which a non-flammable seal is laid; PVC insulation serves as the outer braid
The cable is double insulated:
- the outer shell is made of polyvinyl chloride;
- The inner braid is made of non-flammable PVC.
The internal space between the insulating layers is filled with filler, which is coated rubber. This solution increases the strength of the product and makes it more resistant to high temperatures.
Therefore, NYM cable is one of the moisture- and heat-resistant products. His workers temperature limits from -40 °C to +70 °C.
The only drawback of NYM cable is its vulnerability to UV rays. For this reason, when used on open area where direct rays fall, it is recommended to cover it.
If we compare NYM cable with its VVG analogue, then the first is more preferable in terms of operational parameters. But if you have a limited budget, you can always save money by using the NYM cable only to connect room and apartment panels to the floor panels, and lay VVG cable in the areas.
Type #3 - PUNP wire
Often a budget analogue is used for wiring - flat wire PUNP. It is a two- or three-core product with a cross section of 1.5-6 mm 2. Each strand of the flat wire is made of copper and is single-wire.
PUNP is used to connect permanently installed lighting systems and “power” sockets at a rated network voltage of 250V and at a frequency of 50Hz
The cable is also double insulated:
- the outer shell is made of PVC plastic;
- The inner braid is made of polyvinyl chloride.
In terms of quality, such a wire is far from the best option. In addition, as practice shows, wire insulation is very vulnerable to temperature fluctuations and quickly collapses when heated.
Type #4 - armored cable VBBShV
When arranging a lighting system for the area adjacent to the house, it is impossible would be better suited armored power cable VBBShv. It is designed to operate under alternating rated voltage conditions, the range of which varies from 660 to 1000 V.
It is convenient to install a moisture-resistant product in the ground, in reinforced concrete pipes and in corrugated pipes in the open air, provided that additional protection is created from direct exposure to light rays.
The main advantage of this cable is the presence of metallized armor, and therefore it can be safely used when arranging installation in an earthen trench
The conductive cores of the product are made of copper. The number of threads can vary from one to five, each of which can consist of one or more wire
The cross-section of VBBShV products ranges from 1.5 mm 2 to 240 mm 2. As internal insulation And outer shell polyvinyl chloride is used.
Criteria for choosing wisely
Collateral uninterrupted operation home trunk electrical system is the quality of the components. Therefore, at the stage of purchasing them, one of the key tasks is to choose a cable of appropriate quality.
Manufacturers always indicate what metals the cores are made of and what materials are included in the insulation braid; these parameters are indicated in the cable marking
To help you choose the right cable, you need to carefully study the product labeling. The cable must indicate: brand, manufacturer’s name and compliance with GOST, or technical specifications. The cross-sectional area and cable grade must be repeated at equal intervals along the entire length of the outer braid of the product.
The marking of any electrical cable is represented by numbers and three letters.
The first digit of the numerical designation determines the number of cores, the second digit – the cross-sectional area of each of them, the third – the calculated network voltage. The remaining numbers indicate the flexibility class of the cord. The first letter determines the type of material used to create the top braid of the insulation.
If you have a product in front of you that has the letter “A” in the first place in its marking, this means that the cores are made of silver metal – aluminum; if such a letter is missing, the threads are made of copper
The second letter indicates the wire type:
- « TO» — control;
- « P» - flat;
- « M» — installation;
- « Sh" or " U» — installation;
- « Mg» - mounting with flexible core.
The third letter of the marking determines the material used for internal insulation of the cores.
Options for its designation and decoding:
- « P» — insulation is made of polyethylene;
- « IN" or " VR» — the braid is made of rubber;
- « Pv» — vulcanizing polyethylene is used;
- « Ps» — self-extinguishing polyethylene was used;
- « WITH» — the outer braid is made of lead;
Rubber insulation can be protected by a Nairite sheath " N"or polyvinyl chloride" IN».
An example of decoding the designation: VVG 4x2.5-380 - a cable with four copper cores having a cross-sectional area of 2.5 mm, designed for a voltage of 380 V, insulated with PVC braiding and enclosed in an outer PVC sheath
The following letter indicates the cable type: " NG" - non-flammable and fire-resistant, " B" - armored, " L.S.»—does not emit smoke when melting. Products with an armored shell are used where there is a possibility of mechanical damage.
Presence of the letter “ E"informs that there is filler between the cores. Letter combination " coolant" indicates that this is a single-wire conductor.
How to calculate the wire cross-section?
The cross-sectional areas of the cores are standardized. Their values are selected based on the current strength, core material and laying conditions. After all, when operating the cable to the limit of its capabilities, the cores will heat up by several tens of degrees.
And if several such cables are laid in one tray, then with mutual heating of the products, the permissible current will decrease to 30%.
The calculation is done using this formula P/V.
- R– power of devices, the parameters of which are indicated in the technical documentation;
- V– mains voltage 220 V.
The cross-sectional area is measured in square millimeters. Thus, one “square” of aluminum wire is capable of passing through itself from 4 to 6 Amperes. For the copper analogue, this parameter reaches 10 Amps.
For example, for an electrical appliance with a power of 4 kilowatts, according to this formula, the current becomes equal to 18.18 A = 4000 W/200V. To power such a device, you will need to lay wiring with copper threads with a cross-section of 1.8 mm 2.
As a safety net, it is better to additionally multiply the resulting value by 1.5. Therefore the most perfect option to power such a powerful device - copper wire with a cross section of 2 mm 2. If we consider the option of installing an aluminum analogue, then you will need a cord whose thickness is 2.5 times greater.
The table below will help simplify the task.
Important point! Designing hidden wiring, the data from the table must be multiplied by a factor of 0.8.
If open, it is capable of installation in the same private house; in any case, for reliability, it is better to use a wire with a cross-section of 4 mm 2 and higher, giving preference to products with high mechanical strength.
In terms of the cross-sectional plane, the installation cable for entry into the house should be one step higher than that required for servicing the most installed electrical appliances.
To save money, such a wire can only be used for entry into the house and connected to the terminal block, and lines of the required cross-section can be routed through the machines.
About what cable should be used for electrical wiring in wooden house, learn from our other site.
Conclusions and useful video on the topic
Before choosing and practical application wires, it’s better to remember the theory again by watching useful videos.
Video #1. How to choose the right wire:
Video #2. Expert advice on which wire is better for the home:
The price range of electrical cables on sale is quite wide. But you shouldn’t skimp on this issue. A reduced price may indicate that low-quality materials were used in the production of the cable product, or that the wire has a cross-section smaller than the declared one.
When purchasing products from Chinese manufacturers, be prepared for the fact that in an effort to save money, many of them use copper-plated conductors instead of copper ones. aluminum wires. Externally, they are practically no different from their copper counterparts, but differ only in performance characteristics.