The nuances of choosing wires for wiring in an apartment. Choosing a cable for wiring in an apartment What cable is needed for wiring
When installing electrical wiring, specialists are guided by the requirements of the PUE ( Electrical Installation Rules) and SNiP ( Construction Norms and Rules). These documents are intended for trained specialists. We will not burden the reader with quotes from these smart documents, but will simply give recommendations that are consistent with the regulatory framework.
Almost always, hidden electrical wiring is installed in apartments. Previously, flat aluminum wire in vinyl insulation APPV with a cross section of 2.5 mm 2 was mainly used for these purposes. Currently, such wire is not used for hidden wiring. To lay electrical wiring under plaster, in channels (grooves), in plastic pipes under floor screed, double-insulated electric cable is used.
Criteria for selecting cable products for hidden electrical wiring
You need to understand well that hidden wiring must last for several decades and all this time must work reliably and be safe. When choosing cables for hidden electrical wiring, you need to pay attention to the following parameters
- Cable core material (aluminum, copper);
- Number of cable cores;
- Section of veins;
- The material from which the cable insulation is made.
Properties of aluminum and copper
The cable cores can be made of aluminum or copper. Both materials are suitable for electrical wiring. Aluminum cable is slightly cheaper than copper cable. However, the electrical conductivity of aluminum is 38% lower than that of copper. Therefore, aluminum wires must be thicker than copper wires designed for the same load. The cross sections of wires and cables are standardized. In everyday life, wires from the series 1, 1.5, 2, 2.5, 4, 6, 10, and 16 mm 2 are usually used. When choosing an aluminum cable, it is necessary to use a cross-section one step higher than if using a copper cable. That is, if copper with a cross-section of 1.5 mm 2 is suitable for a given consumer, then the aluminum cable should have a cross-section of 2 mm 2.
There are differences in other properties of the materials. For example, copper wire is more resistant to repeated bending. This is why flexible (stranded) wires are made only from copper. Aluminum is a more fluid material than copper. Therefore, it is necessary to “maintain” the contacts with the aluminum wire more often, periodically “tightening” the screw terminals with a screwdriver or wrench. If this is not done, heating may occur in places of poor contact. Also, copper wire is less susceptible to oxidation and its aging occurs more slowly than aluminum.
In modern practice, experts give preference to copper wires and cables. When choosing a copper cable, you should pay attention to the rigidity of the conductors. Cores that are too soft indicate poor quality of the material, and copper cable that is too hard is more difficult to work with.
Number of cable cores
Most houses use single-phase input into the apartment. For single-phase input, the Rules require electrical wiring to be carried out with three wires. This means that in addition to the phase and neutral wires, a protective grounding wire must be connected to sockets and electrical appliances. Its main purpose is to protect people from electric shock. This wire may be present in the power cable or laid separately. The first option is more convenient when all three wires are laid from one place, for example, from a lighting panel. The second option is used if the grounding line is located in a different location.
The cable cores must be color coded. The protective ground wire should be yellow-green in color. The neutral wire is painted blue or white with a blue longitudinal stripe. Phase wires are usually painted black, brown, orange, white or red.
Above we looked at the number of cores in the cable; it should not be confused with the number of wires in the core. Copper cable can have single-wire and multi-wire cores. Cables with stranded cores are flexible. They are a little easier to install. However, it is impossible to connect them directly to the often used self-clamping spring terminals, and also to screw terminals. The ends of the multi-wire cable must be either tinned or lugs pressed onto them. Therefore, the use of flexible cables for hidden electrical wiring is not recommended.
Selection of cable cross-section
We have already mentioned that the cable cores have standard cross-sections. The choice of cable cross-section is determined by the maximum load current that will be connected to it. The cross-section is calculated based on the material of the cable cores and the maximum permissible heating for a given cable brand. In this case, the number of cable cores, the installation method, the number of adjacent cables, and the ambient temperature are taken into account.
In order not to bore the reader with complex calculations, let’s say that for lighting loads for hidden wiring, a copper cable with a core cross-section of 1.5 mm 2 is suitable. Such a cable can power a load consuming current up to 15A. This is 3.7 kW of electrical power in a 220V network. This cable cross-section is quite sufficient to illuminate any room and even most apartments. To power the sockets, you can use copper with a cross section of 2.5 mm 2. A cable with a hidden cross-section can withstand a current of 25A, or 5.5 kW. To power an oven, hob or electric stove, depending on their power, cables with a cross-section of 4 - 6 square are suitable. Electrical input into the apartment, depending on the total power of all electrical equipment, is usually carried out with a cable with a cross-section of 10 or 16 mm 2. Let us remind you that if the electrical wiring is carried out with an aluminum cable, then its cross-section should be one step higher.
Before purchasing, it’s a good idea to make sure that the cross-section of the cable’s cores corresponds to its brand. Many practical electricians say that they have encountered a discrepancy between the cable cross-section and its markings. Let us recall that the cross-sectional area of a round conductor is calculated by the formula:
The diameter of the conductor can be measured using a caliper or micrometer. It is better to take measurements in several places of each core.
Cable insulation material
For hidden wiring, vinyl-insulated cables (polyvinyl chloride, polyvinyl chloride) are best suited. This material “works” in a wide temperature range: -50 o +50 o C. It is resistant to various environmental factors. The operating voltage can be 660V/1000V. The guaranteed service life of vinyl insulated cables is 30 years.
In recent years, the industry has begun to produce vinyl-insulated cables with improved characteristics. In the cable markings you can find the indices “ng”, “ls”. The index “ng” means that the cable does not support combustion when laid alone. In other words, a cable with the index “ng” does not burn in the absence of an external heat source. The index “ls” (from English low smokin) means low smoke emission.
To summarize, we can say that the widely used three-core cables of the VVGngls and AVVGngls brands of the appropriate cross-section are ideal for installing hidden electrical wiring in an apartment.
A large assortment of electrical products is presented on store shelves. There is no exception for electrical wiring. It is difficult for an untrained user to understand which cable to use for wiring in an apartment.
Many people consider the above concepts to be synonyms. Products can be identified by manufacturer's markings. Mostly, a cable is meant to be covered with durable two-layer insulation, one of which covers the conductive cores, and the second covers the entire complex.
The wire is characterized by lighter insulation, giving a weakened structure to this element. Sometimes it is double, but in its open form it is characterized by instability under conditions of aggressive influence. It is not resistant to prolonged loads and is easily flammable. When deciding which wires are best to use for wiring in the house, it makes the most sense to choose cables.
The buyer must understand that cross-section and diameter are different concepts. The first is the area of the circle, calculated as 0.785 square of the diameter. This figure is always rounded up when purchasing.
Popular brands for electrical wiring
GOST 31565 regulates the use of fire-resistant electrical wiring. It allows the following types of cables to be used when making internal wiring:
- ng-LS - having a slight gas and smoke emission;
- ng-HF - do not emit halogens during smoldering and gas-based products during combustion.
The variety is classified as type 1, and variety as type 2.
Below we consider non-flammable wiring cables of the VVG and NYM brands. The advantages of using them include:
- a large assortment;
- high fire safety;
- convenient installation;
- high-quality execution;
- high durability;
- low smoke and self-extinguishing.
VVG cable
For many experts, the question of how to choose a wire for laying in a residential area is not worth it. They use the VVG brand. Single-core copper conductors are used here. It has become widespread in buildings with normal or high humidity. The maximum permissible voltage is 660 V. 1 element contains 1-5 cores, cross-section 1.5-240 mm². Conductors vary in shape: from triangular to flat.
Several models are produced, differing in insulation parameters:
- VVG - with insulation and vinyl sheath;
- similar with the index “ng” - equipped with insulation with a self-extinguishing function;
- “ng” - variety with the continuation -LS - similar non-flammable insulation of cores with low smoke emission from the shell;
- VVGng FR-LS - in addition to the advantages of the previous modification, it has additional fire protection in the form of a mica tape.
All “ng” varieties are suitable for mounting in bundles (1 carrier). They are also used for electrical wiring in the country.
Read more about this in our article.
NYM cable
Was created in Germany. Produced in the Russian Federation. Copper conductor is used. Adherents of European goods are better off using these cables for wiring in the apartment. Similar in design to VVGnm. It can be single-wire, with a cross-section of 1.5-10 mm², and multi-wire - from 16 mm². The composition includes a rubber filler that provides non-flammability and is located between the core insulation and the sheath. The cable for sockets is used with a cross-section of 3x2.5, for switches - 3x1.5.
You can find out more about it in our article.
Which wires are not suitable?
Carrying out electrical wiring in an apartment not with a cable, but with a wire, even multi-core or double-insulated, is not a good idea. They are highly flammable with prolonged use. The wires do not meet the requirements of the PUE for residential buildings. Therefore, if there is a choice and opportunity, then when asked which wire to use for wiring, you need to answer that a cable is used.
Extension cords are made from it and household electrical appliances are connected to home wiring. The work is carried out up to 380 V, the number of conductors is 2, the cross-section of the stranded core is 0.75-10 mm². Copper conductor wrapped in vinyl materials is used.
Wiring is of low quality. The cost is low, but it is offset by the increased price of work:
- the connecting ends must be tinned and soldered;
- has an increased risk of fire due to the stranded core;
- does not imply their presence in 1 device.
Wires and cords ShVVP, PVVP
Copper conductors, single- and multi-wire. Connect household electrical appliances. There is no non-combustible insulation. The service life is short. Not used for fixed wiring.
Wire PUNP
Due to its unreliability, this wire has been banned from electrical wiring since 2007. Was allowed in the USSR. Today, due to the use of high-power equipment, it is not able to withstand increased loads. Has poor insulation.
Currently, for the installation of home electrical wiring, wires and cables are used exclusively with copper conductors. Wires and cables with aluminum conductors cannot be used for internal electrical wiring.
Wires and cables can be single-core or multi-core. Multicore wires and cables have two or more cores reliably insulated from each other in a common sheath.
Example - wire brand PRTO(wire with copper core with rubber insulation, braided with cotton yarn , impregnated with anti-rotten composition).
The cores of single-core and multi-core wires and cables can be made single-wire and multi-wire.
Cables and wires differ from each other in the type of sheath and names. The sheath of wires and cables serves to protect the insulation of the cores from exposure to light, moisture, various chemicals and prevent them from mechanical damage. The cable may include armor, and the sheath allows it to be installed in more adverse environmental conditions.
Wires can only be laid in a hidden way, and only in boxes. Cables can be laid openly.
The most popular cable for use in home electrical wiring is VVGng; NYM cable and PUNP wire are less commonly used.
To connect to the floor panel, it is best to use an NYM cable. The same cable is used to connect the floor panel with the apartment or room panels (provided that they exist). Usually such shields are organized in private cottages. It can also be used for individual connection of powerful consumers. You can use this cable to do everything in an apartment or house, but since it costs more than VVGng cable and PUNP wire, it is used less often for these purposes.
VVG - unarmored protected cablewith copper conductors, polyvinyl chloride insulation, in a polyvinyl chloride sheath. The cable can be used in dry and damp areas.
The VVG cable is not designed for tension. The insulated cores of the VVG cable are twisted and have a distinctive color. The inner shell does not contain filling in the intervein space.
Rice. 1. VVGng cable
ABOUT The designation “ng” in the name of the cable (VVGng) means that it does not propagate combustion when laid in bundles (a composition based on fire-resistant plastic is used). If VVG cable is used instead of VVGng cable, then if one of the cables catches fire, the flame will spread to other cables instead of localizing the fire.
The VVGng cable has a wide variety of shapes. It is most convenient to use a VVGng flat cable. In addition, it can also be round, square, sector, and even triangular.
NUM cable (NYM) - produced according to German standard DIN 57250. The cable can be used indoors for hidden and open installation. Cable NYM Can be used outdoors, only out of direct sunlight. Cable NYM has reduced flammability and gas and smoke emissions, which is especially important for residential premises.
Figure 2. NYM cable
NYM cable consists of copper cores, an intermediate sheath of chalk-filled rubber and a sheath of flame retardant polyvinyl chloride insulation. The use of an intermediate sheath in the cable design makes it easy and convenient to cut the cable during installation, increases its fire hazard and increases flexibility.
PUNP - installation flat wire. This is the cheapest wire of all cable and wire products used for installing electrical wiring in the home. PUNP wire is produced with two or three single-wire copper cores and polyvinyl chloride insulation in a PVC sheath. The veins can be painted in different colors.
Rice. 3
PUNP wire is only available flat. These cable and wire products are used for both power and lighting networks. In the second case, wires of smaller cross-sections are used.
I do not recommend using PUNP wire when laying home electrical wiring, since the insulation of this wire is made of cheap materials and very quickly loses its properties when heated. When choosing a cable for electrical wiring, give preference to cables of the VVGng or NYM brands.
Much less often in home electrical wiring, rubber-insulated wires of the PRN, PRI, and PRTO brands are used. The PRTO wire is intended for laying in fireproof pipes, PRI - can be used for laying in dry and damp rooms, PRN (protected wire) - in the open air, PRD, PRVD (two-core twisted wire) - only in lighting networks of dry rooms.
For open wiring, it is convenient to use a flat wire with copper conductors and polyvinyl chloride insulation with a dividing base of the PPV brand, as well as a wire with polyethylene insulation PPP. There is a flat wire without a dividing base - PPVS, but it is not very convenient to use.
Previously used wires with aluminum conductors (APR, APV, APRTO, APPV) are now not used in the construction and modernization of home electrical wiring.
Wire with copper core and polyvinyl chloride insulation PV. PV wires can be single-wire or multi-wire. Wires are available with different insulation colors. In household electrical wiring The base wire PV1 in yellow-green coloring is used for the potential equalization system (PSUP).
Rice. 4.
Wires PV2, PV3 and PV4 are used for internal installation in electrical panels. Wires PV3 and PV4 are usually more expensive , because have a more flexible shell. They are used where wire bends are necessary.
To power street lamps, underground they use armored cable VBBShv, or cable with aluminum conductors AVBbShv. This cable is protected by steel tape under a layer of polyvinyl chloride insulation.
Rice. 5. Cable VBBShV
The VBBShV cable is available with three, four and five conductor cores. Previously, cables with copper conductors in a polyvinyl chloride sheath VRG and armored cables with aluminum conductors of the AAShv, AAB, AVVB and AVRB brands were used for these purposes.
For air branches in our time the most popular. There are a large number of varieties of such cables: SIP-2A, SIP-3, SIP-4. The cable has high-strength steel-aluminum cores. The cores are insulated with special light-stabilized, weather-resistant polyethylene, which does not collapse in the open air.
Earlier for making air branches AVVG cables with conventional polyvinyl chloride insulation were widely used, which quickly became brittle and destroyed under the influence of adverse environmental factors. The use of self-supporting insulated SIP cable solves this problem.
When choosing wires and cables, you must follow PUE requirements for insulation painting.
The insulation of the neutral working conductor should be blue, the neutral protective conductor should be yellow-green. The color of the insulation of phase conductors must be different from the color of neutral conductors. There are many options here - brown, red, grey, white, black, etc.
Rice. 6. Color options for wires and cables
It is also very convenient to use a different color of phase conductors for each section of electrical wiring, as well as different colors of core insulation for power and lighting wiring.
If you choose and then install electrical wiring with a wire or cable without complying with the requirements for the colors of the wires, then in the future this will lead to significant difficulties in maintaining and repairing such electrical wiring, and the installation process itself can be very complicated, especially when using a large number of switches and sockets. In addition, the use of wires and cables with insulation of the same color is a violation of the PUE.
The modern market offers a wide selection of cable and wire products from various manufacturers and brands, each of which serves to perform specific tasks (power supply or operational part of electrical equipment, connecting a TV or the Internet, etc.).
In this article we will look at the most popular brands of cables for installation in a home or garage.
How to choose the right electrical cable for wiring
In most cases, VVG (VVGng) 3*2.5 mm cable is used for installation (the “ng” marking in the name indicates that the product does not support the spread of combustion).
This is a single-core vinyl-insulated cable with a cross-section of 2.5 mm, which can withstand currents of up to 21 A (4.6 and 7.9 kW, respectively, with single-phase and 3-phase power).
This type of cable is ideal for powering household equipment, sockets, small heaters, coffee makers, washing machines, etc.
Cable for connecting an electric stove or oven
If you need to power a modern electric stove or oven (with a power of up to 7 kW), then such a cable will no longer be enough. For such needs, with single-phase “power supply” it is necessary to use a cable with a minimum cross-section of 4 mm2 (for example, PVS 3x4 or VVG 3x4).
The main difference between these cable brands is the design of the supply core.
To make it clearer, the VVG cable is made of one solid core with a cross-section of 4 mm2 and is intended for permanent installation, while the PVS cable is a flexible multi-core cable that is used for temporary installation.
Lighting cables
In most cases, to power the lighting network of a house or garage, it is enough to lay a VVG 3x1.5 cable. Since the lighting network consumes a small current, this cross-section will be quite sufficient.
In combination with it, for reliable protection of the lighting network, it is also necessary to install an additional circuit breaker with a rating of 10A.
However, if you have a converter that converts alternating current 220 V into direct current with a nominal value of 12 V, often used in bathrooms for safety, then you need a larger cross-section (for example, VVG 3x2.5).
Garage power cable
Since garages often use a 3-phase power supply system, it is no longer appropriate to use a regular VVG 3x2.5 cable.
For these purposes, the best option is VVG 5x2.5. This is a 3-phase wire with a neutral and grounding conductor.
However, if your garage is equipped with powerful equipment, such as pumps, various machines, high-power welding transformers, etc., then you simply need to increase the cable cross-section to 6-10 mm2.
How to decipher the markings on the cable
For example, let's decipher the name of the most common cable VVG3x2.5.
- B - vinyl;
- B - vinyl;
- G - flexible;
- 3 - number of cores;
- 2.5 - core cross-section.
That is, it is a vinyl 3-core copper cable with a cross-section of each core of 2.5 mm2. If the name of the cable is preceded by the letter A, for example, AVVG 3x2.5, this will mean that it is an aluminum cable.
Which cable is better to use when supplying electricity to a house or garage?
There is, of course, no clear answer to this question, since there is no single correct solution.
Some specialists use flexible cable PVS, others VVG, but there are still craftsmen who use aluminum cable AVVG due to its low cost. But such cable and wire products have the following disadvantages:
- It has low electrical conductivity (high resistance);
- Short service life;
- Increased fragility (with 5-6 bends it breaks);
- For laying around the apartment when using a copper cable, 2.5 mm2 is sufficient; in the case of installing AVVG, its cross-section must be at least 4 mm2.
What cross-section should the entrance to the apartment house be?
If you need to lay a cable from the distribution panel to the apartment, then the best option is VVG 3x6.
Also, do not forget that when laying such a cable, it is necessary to install an appropriate circuit breaker to protect against short circuits.
If the input is made of a cable with a cross-section of 6 mm2, the machine must have a current cut-off of 80A.
If you have a private house, for electrical installation you need to use a special 4x16 SIP wire (self-supporting aluminum wire), which is recommended for laying along the supports and walls of the building.
conclusions
A properly selected cable will allow you to protect your equipment, household electrical appliances and ensure trouble-free operation for many years.
The choice of cable must be made in accordance with technical specifications. conditions and characteristics of a particular situation. The ideal option is to entrust this task to professionals, but if you want to save money, it is better to read a couple of dozen articles about “how to choose the right cable for a garage or home” before starting work.
Because in case of poor-quality installation or violation of the requirements of PTEEP, PTB or PUE, you put yourself, your loved ones and neighbors at risk. After all, 70 percent of all fires are caused by electrical short circuits.
It is important to select all components for electrical installation work, including cable products. Much will depend on the cross-section, brand and even manufacturer, from the durability of the home electrical network to the safety of its use. In this article we will try to explain in detail how to choose a cable for electrical wiring in an apartment and a house (including a wooden one).
Cable or wire?
The first thing you need to understand is that you need to use an electric cable to distribute electrical wiring throughout your living space. There are several reasons why you cannot select a wire for electrical wiring:
- Electrical wires can be laid either in a hidden way inside the walls, or when wiring in the floor. Moreover, the conductor must be placed in a corrugated or HDPE pipe.
- Wires are less resistant to prolonged heating; moreover, they may have single insulation, and therefore their protective properties are not sufficient, and the likelihood of fire is many times higher.
- The cables have better performance characteristics, including service life (30 years compared to 10).
As you can see, there are quite good reasons (and this is not all) why it is better to choose a cable rather than a wire for electrical wiring. That is why further we will talk specifically about the rules for choosing cable products for distributing electricity around the house and apartment.
Criterias of choice
To select the correct cable for wiring, consider the following recommendations:
The conductor must be three-wire(as in the photo below) , because Today it is very important to do grounding in residential buildings. Even if you don’t have one yet, but plan to replace the electrical wiring in the apartment, it is better to choose a three-core conductor and simply temporarily not use the yellow-green wire (insulate it).
Core material - required copper. Aluminum wiring is no longer used and is also prohibited by the rules of the PUE. You can read about it in our separate article.
It is very important to choose the right section cable for wiring. To do this, you need to know the total power of all electrical appliances or perform a more accurate calculation of the cross-section - based on the current load. Knowing the current strength, just use the table below and select the appropriate core size. You can learn more about it in our article. If we talk about standard sections, then for lighting they use 1.5 mm2, and for the power line (socket) you need to choose 2.5 mm2. To connect an electric stove and other household appliances where electricity consumption is high, the cross-section of the electrical wiring must be at least 4 mm2. The values are for copper conductor.
Also, one of the most important criteria for choosing a cable for electrical wiring is its brand. Since there are quite a lot of different product names on the cable market, you need to study the characteristics of the commonly used ones and choose the appropriate option for your own conditions. For home wiring, we recommend using, or (the last two conductors do not propagate combustion, so they are best chosen for electrical wiring in a wooden house and a dressing room in a bathhouse). VVG can be used for electrical wiring in an apartment, as well as in outbuildings, for example, in a garage. It is recommended to use heat-resistant ones directly in the steam room. On the street, it is better to stretch it from the pole to the house.
Well, the last thing you should pay attention to when choosing is manufacturer cable products. Beware of fakes and unverified brands, because in this case, for reasons of economy, the plant can save on the cross-section of conductors, the thickness of the insulation and the quality of the insulating layer itself. As a result, this may lead to adverse consequences, for example, overheating and fire of the electrical wiring when connecting the load for which it should have been designed. ABOUT
