Cables used to build computer network infrastructure are available in a wide range of varieties. Among the most popular are coaxial, twisted pair, and optical fiber. What are the specifics of each of them? What are the features of installing the most common type - twisted pair?

Cable types: coaxial

Among the historically earliest types of cables used in network connections is coaxial. Its thickness is approximately the same as that of a computer power supply, designed to work with a 220 V outlet.

The structure of the coaxial structure is as follows: in the very middle there is a metal conductor, it is wrapped in thick, most often plastic, insulation. On top of it is a braid of copper or aluminum. The outer layer is an insulating shell.

The connection of the network cable of the type in question can be done by:

BNC connector;

BNC terminator;

BNC-T connector;

BNC barrel connector.

Let's consider their specifics in more detail.

The BNC connector is supposed to be placed at the ends of the cable and is used to connect to T- or barrel connectors. A BNC terminator is used as an isolating barrier that prevents signal movement along the cable. Correct functioning of the network without this element is in some cases impossible. A coaxial cable requires the use of two terminators, one of which requires grounding. The BNC-T connector is used to connect the PC to the main line. There are three slots in its structure. The first one is connected to the computer connector; the other two are used to connect different ends of the line. Another type of connector for coaxial cable is the BNC barrel. It is used to connect different ends of a highway, or to increase the radius of a computer network.

Among useful features coaxial designs - no problem deciding how to connect two network cables of this type. It is enough to ensure reliable contact of the conductive cores, of course, subject to the technology of pairing the insulation and the screen mesh. However, coaxial cable is quite sensitive to electromagnetic interference. Therefore, in the practice of building computer networks, it is now used quite rarely. However, it is indispensable in terms of organizing the infrastructure for transmitting television signals - from dishes or cable providers.

twisted pair

Probably the most common network cables for computers today are called “twisted pair”. Why this name? The fact is that the structure of this type of cable contains paired conductors. They are made of copper. A standard cable of the type in question includes 8 cores (thus, 4 pairs in total), but there are also samples with four conductors. The so-called pinout of a network cable of this type (correlating each core with a particular function) involves the use of insulation a certain color on each conductor.

The external insulation of the twisted pair is made of PVC, which provides sufficient protection of the conductive elements from electromagnetic interference. There are the types in question - FTP and STP. In the first, the foil performing the corresponding function is located on top of all the cores, in the second - on each of the conductors. There is an unshielded modification of twisted pair - UTP. As a rule, cables with foil are more expensive. But it makes sense to use them only if there is a need for high-quality data transfer over relatively long distance. For home networks, an unshielded twisted pair version is quite suitable.

There are several classes of the corresponding type of structure, each of them is designated as CAT with a number from 1 to 7. The higher the corresponding indicator, the better materials, providing signal transmission. Modern network cables for computers for data exchange via Ethernet in home networks require elements to comply with CAT5 class. In connections that use twisted pair, connectors are used that would be correctly classified as 8P8C, but there is also an unofficial name for them - RJ-45. It can be noted that cables that meet at least the CAT5 and CAT6 classes can transmit data at speeds close to the maximum for the type of structure under consideration - up to 1 Gbit/s.

Optical fiber

Perhaps the most modern and fastest network cables for computers are fiber optic cables. Their structure contains light-conducting glass elements, which are protected by durable plastic insulation. Among the key advantages of these network cables for a computer is high immunity to interference. Also, data can be transmitted over a distance of about 100 km via optical fiber. The connection of cables of the type in question to devices can be carried out using various types connectors. Among the most common are SC, FC, F-3000.

What does this high-tech network cable for a computer look like? Photo of the fiber optic structure below.

The intensity of practical use of optical fiber is limited by the fairly high cost of the equipment necessary to transmit data through it. However, recently many Russian providers have been actively using this network cable for the Internet. According to IT experts, with the expectation that the corresponding investments will pay off in the future.

Evolution of cable infrastructure

Using the example of the three noted types of cables, we can trace some evolution in the aspect of building computer network infrastructure. Thus, initially, when transmitting data via the Ethernet standard, coaxial structures were used. At the same time, the maximum distance over which a signal could be sent from one device to another did not exceed 500 meters. The maximum over coaxial cable was about 10 Mbit/sec. The use of twisted pair cables has significantly increased the dynamics of file exchange on computer networks - up to 1 Gbit/sec. It also became possible to transmit data in duplex mode (one device could both receive signals and send them). With the advent of optical fiber, the IT industry was able to transfer files at speeds of 30-40 Gbit/sec or more. Thanks largely to this technology, computer networks successfully connect countries and continents.

Of course, when working with a PC, many other types of cables are used that are used in the installation of computer networks. Theoretically, for such purposes, you can use, for example, a USB cable, although this will not be very effective, in particular, due to the fact that within the USB standard, data can be transferred over a short distance - about 20 m.

How to connect twisted pair

Twisted pair, as we noted above, is today the most common type of cable in the design of computer networks. However, its practical use is characterized by some nuances. In particular, they reflect such an aspect as the pinout of the network cable, which we mentioned above. It is important to know how to correctly position the wires in the area where they come into contact with the RJ-45 connector. The procedure by which a twisted pair is connected to the corresponding element is called crimping, since during its implementation a special tool is used that involves force on the structure.

Nuances of crimping

During this procedure, the connectors are securely fixed to the ends of the twisted pair. The number of contacts in them corresponds to the number of cores - in both cases there are 8 such elements. There are several schemes within which twisted pair cables can be crimped.

Next we will look at the relevant specifics. But first, the person working with the cable needs to properly hold the connectors in their hands. They should be held so that the metal contacts are located on top.

The plastic latch should be directed towards the person doing the crimping. In this case, the 1st contact will be on the left, and the 8th contact will be on the right. Numbering is an extremely important aspect of working with twisted pair cable. So, what crimp schemes are used by network infrastructure specialists?

First, there is a network cable design called EIA/TIA-568A. It assumes the arrangement of the cores in relation to the metal contacts of the connector in the following order:

For 1 contact: white-green;

For the 2nd: green;

For the 3rd: white-orange;

For the 4th: blue;

For the 5th: white and blue;

For the 6th: orange;

For the 7th: white-brown;

For the 8th: brown.

There is another scheme - EIA/TIA-568B. It assumes the arrangement of the cores in the following order:

For 1 contact: white-orange;

For the 2nd: orange;

For the 3rd: white-green;

For the 4th: blue;

For the 5th: white and blue;

For the 6th: green;

For the 7th: white-brown;

For the 8th: brown.

You now know how to connect a network cable to a connector. But it is useful to study the specifics regarding various schemes connecting twisted pair cables to certain devices.

Crimping and connection type

So, when connecting a PC to a router or switch, you should use the direct connection method. If there is a need to organize file exchange between two computers without using a router, then you can use the cross connection method. The difference between the marked schemes is small. At direct method connections, the cable must be crimped using the same pinout. When crossed, one end is according to circuit 568A, the other is according to 568B.

High-tech savings

Twisted pair is characterized by one interesting feature. With a direct connection scheme, the device can use not 4 pairs of conductors, but 2. That is, using one cable it is permissible to connect 2 computers to the network at the same time. This way you can save on cable costs or make a connection if you really need to do this, but you don’t have extra meters of twisted pair at hand. True, in this case the maximum data exchange speed will not be 1 Gbit/sec, but 10 times less. But for organizing homework, it is acceptable in most situations.

How to distribute the cores in this case? In relation to the contacts on the connection connectors:

1 contact: white-orange core;

2nd: orange;

3rd: white-green;

6th: green.

That is, 4, 5, 7 and 8 cores are not used in this scheme. In turn, on the connectors for connecting a second computer:

1 contact: white-brown core;

2nd: brown;

3rd: white-blue;

6th: blue.

It may be noted that when implementing a crossover connection scheme, you must always use all 8 conductors in a twisted pair. Also, if the user needs to implement data transfer between devices at a speed of 1 Gbit/sec, the pinout will need to be carried out according to a special scheme. Let's consider its features.

Gigabit speed cross-connect

The first cable connector should be crimped according to diagram 568B. The second assumes the following comparison of cores and contacts on the connector:

1 contact: white-green core;

2nd: green;

3rd: white-orange;

4th: white-brown;

5th: brown;

6th: orange;

7th: blue;

8th: white and blue.

The circuit is quite similar to the 568A, but the position of the blue and brown wire pairs has been changed.

Compliance with the marked rules for matching the colors of cores and contacts on the 8P8C connector is the most important factor in ensuring the functionality of the network infrastructure. The person designing it must be careful when installing the relevant elements. It happens that the computer does not see the network cable - this is often due to incorrect crimping of the twisted pair cable.

How to crimp a cable correctly

Let's look at some technical nuances. The main device that is used in this case is a crimper. It is similar to pliers, but at the same time it is adapted to work specifically with computer cables of the appropriate type.

The design of the crimper requires the presence of special knives designed for cutting the structure. Also, sometimes crimpers are equipped with a small device for stripping twisted pair insulation. In the central part of the tool there are special sockets adapted to the thickness of the cable structure.

The optimal algorithm for the actions of a person crimping a twisted pair cable may be as follows.

• First of all, it is necessary to cut a section of the cable of suitable length - thus, precise measurements will be required.
• After this, the outer insulation should be removed - approximately 3 cm at the end of the cable. The main thing is not to accidentally damage the core insulation.
• Then you need to arrange the conductors in relation to the connection diagrams to the connector discussed above. Afterwards, trim the ends of the cores evenly, so that the length of each of them outside the outer layer of insulation is about 12 mm.
• Next, you need to put the connector on the cable so that the wires remain in the order that corresponds to the connection diagram, and each of them fits into the desired channel. You should move the wires until you feel resistance from the plastic wall of the connector.
• After the cores have been properly positioned inside the connector, the PVC sheath should be positioned inside the connector body. If you can't do this, you may need to pull out the wires and shorten them a little.

Once all the structural elements are positioned correctly, you can crimp the cable by inserting the connector into a special socket on the crimper and smoothly pressing the tool handle until it stops.

Major home renovations necessarily include replacement of electrical wiring. There are two main reasons for this action.

The first is the age of this wiring itself. As a rule, major or any serious repairs are carried out 15-20 years after the apartment is handed over. During this time, even a properly made home electrical network ages and wears out. This means it potentially becomes a source of danger for the inhabitants of the home.

The second reason is redevelopment and big renovation separate rooms with the addition of new electrical appliances. Tie-ins and other connections of new wiring with old are extremely undesirable. Due to a mismatch in the characteristics of the cable or materials in it.

So, the question of whether to change the electrical wiring is considered resolved; it remains to deal with its practical implementation. And you need to start with choosing a cable.

Cable for electrical wiring in an apartment - 300 brands and 5000 varieties

Which side should we start with? A person who is far from electrical installation will grab his head. And there is something to grab onto. Because there are not just a lot of cables and wires, they literally cannot be counted, like Don Pedro in Brazil. Even professional electricians sometimes get overwhelmed and confused by the abundance of manufacturers and products.

The choice of wire for electrical wiring in an apartment is not only a question of the cost of repairs. A much more important point is that the wiring must ensure the “delivery” of electricity to any corner of the apartment and be safe, that is, not “bite” with current. And also be fire resistant and reliable.

Attention! The key to reliable electrical wiring is finding the right electrician. A specially trained technician must do electrical work and select cables for wiring in an apartment! Who has access to electrical installation work and practical experience.

We will briefly talk about cables and wires, their cross-section, markings, materials and types. We will explain what is suitable for home wiring and what cannot be used. So that you are aware of what your electrician is doing and why.

Characteristics of wires and cables that you should pay attention to when choosing

Let us immediately clarify that we are talking about a household power cable or wire with a voltage of 220/380 V for transmitting electric current in a home network. We are not currently considering all other types such as heating, television, computer and others.

The general list of characteristics looks like this:

• core material;
• design;
• section;
• thickness of conductor insulation;
• shell thickness;
• marking;
• core color;
• package;
• certificate;
• product condition.

1. Material and design

According to the composition of the vein, cable products are divided into copper and aluminum. Copper products are more reliable, the resistance is lower, the current is higher, and the heating is less when compared with aluminum of the same cross-section. In addition, copper oxidizes less and is more ductile, which means the cable lasts longer without loss of properties and characteristics.

Attention! Do wiring in the apartment aluminum cable prohibited according to the requirements of the PUE (electrical installation rules).

By design single-core (single-wire) and multi-core (multi-wire) cables and wires are produced. Single-core varieties are more rigid and inflexible, especially with a large conductor cross-section.

Answering the question “which wire to use for wiring under plaster,” we can say that theoretically a single-core single-wire copper cable is also suitable. Plaster will create additional protection for such a conductor. But in fact, no one lays a single-wire home electrical network.

Multi-wire single-core cable is softer and more flexible. It tolerates bends and turns well and is suitable for both open wiring and hidden wiring under plaster. It is the three-core single-wire that is now used for laying in apartments.

Attention! Do not confuse cables in which each core consists of one conductor with wires where the core is made of several conductors. Multi-wire cable products are prohibited for permanent installation in an apartment due to the high fire hazard. Read more about them in the block“which wires should not be used for electrical wiring in an apartment”

2. Cable cross-section for wiring in an apartment

It is measured in “squares”, that is, square millimeters and shows the throughput. For a copper cable, one “square” carries 8-10 Amperes of current, for an aluminum cable only 5 A. For safe operation, the conductor should be selected with a reserve of carrying capacity, which ensures heating of the wire within the permissible value, or, more simply, so that it does not “float” under the load. insulation. In addition, with hidden wiring, it must be taken into account that it is cooled less efficiently, which means that the cross-sectional reserve must compensate for this.

Attention! Do not confuse the cable cross-section with its diameter, these are two big differences! The diameter can be measured with a ruler, or better yet, with a caliper. And then substitute it into the formula and calculate the cross-sectional area.

Also remember that the choice of cable for wiring in an apartment is always rounded up. If the calculation results in 2.3 “squares”, a two and a half cable is selected, not two “squares”.

Ideally, the cross-section should match the marking on the cable tag, but in fact it often differs to a smaller extent. Small discrepancies are acceptable because the cable is certified by resistance, not by wire cross-section. If the discrepancies are significant, it is a marriage. An experienced electrician will see it visually, and you can measure the diameter of the core and calculate the cross-section for interest or to help a friend who independently decides to buy a cable for apartment wiring.

Some electricians advise using a cable with a rating higher than the calculated one. For example, 4 “squares”, instead of 2.5, to cover the “shortage” of the section, if there is one. But then you will have to calculate the wiring protection accordingly and install the correct machines and RCDs.

Advice! For electrical wiring in an apartment, we recommend a cross-section of copper wires from 1.5 to 2.5 square meters. mm. Allow two and a half “squares” for sockets and one and a half for lighting.

3. Wire insulation thickness

Each core in a multi-core or single-core cable has insulation made of PVC plastic of the usual type or with reduced flammability; polymers and cross-linked polyethylene are also used. The thickness of the insulation is regulated by GOST standards and it must be sufficient. For household cables (rated voltage up to 660V) with a cross section of 1.5 and 2.5 mm 2 the thickness of the insulating layer according to the standard is 0.6 mm. Deviations are allowed, but the insulation should not be thinner than 0.44 mm.

Simply put, there is a range of thicknesses where the insulation must “fit” so that the wiring serves reliably and there are no problems during installation. Whether the manufacturer violated the technology cannot be determined without a micrometer unless you tinker with the cables every day. Therefore, if there is no experienced electrician nearby, you should only buy cables from well-known brands in trusted stores.

4. Shell thickness

The sheath encloses the cable over the insulated cores, secures them and protects them. It is made, like the core insulation, from PVC plastic or polymer, but is thicker. For multi-core cables, the thickness is 1.8 mm, for single-core cables - 1.4 mm. Deviations in a smaller direction are also possible, but insignificant.

The insulating shell is a mandatory element. For any residential wiring cable, even with minimal power, double insulation is prescribed. That is, first on the core, and then on top of it. This ensures the safety of people and protects the conductor itself from damage.

5. Marking

This is the inscription on the cable sheath for installing electrical wiring in the apartment. It contains everything necessary information for selection. The inscription is printed or extruded during the manufacture of cable products. It should be clear, contrasting, and easily readable.

The labeling indicates:

• Brand of product (cable or wire), which encodes the main properties and characteristics.
• Manufacturer's name.
• Year of issue.
• Number of cores
• Section.
• Voltage rating.

The inscription is applied along the entire length of the conductor at small intervals.

On the price tag and in catalogs of online stores, they usually do not indicate the year of manufacture and manufacturer and write the marking in the form VVGng(ozh)-0.66 kV 3x1.5 or VVG, VVGng cable 3x1.5.

It stands for three-core copper cable with a core cross-section of 1.5 “square” (3x1.5), single-wire core design (ozh). Insulation and sheath made of PVC compound (VV), flexible cable (G), non-flammable (ng). Rated voltage 660 Volts.

Remember! The letter designation of the cable brand begins with the core material; for aluminum the letter A is always used, for copper — the letter is not indicated, therefore all VVG brand cables of all modifications have a copper conductor.

6. Core colors

What you need to know about the color is that it is either a solid color or a stripe is applied to the sheath along the entire cable, approximately a millimeter wide. This is the standard. Everything else, in the form of smears, spots, stripes across it, is from the evil one. And he says that strange people were making the cable in some basement.

There is a table for the colors of the cores that any experienced electrician knows. It describes what shade the main conductors are denoted by - phase, neutral, grounding. This was done for convenience during installation, in order to see where to connect which conductor. Phase and working conductors may differ in color, but the “ground” is always “painted” yellow-green.

7. Packaging

Standard for all types is a coil or drum. The coils are sold to stores and wound onto drums for wholesalers, builders and other large buyers. In any case, a label with a description is attached to the cable.

The contents of the tag repeat the information on the inscription on the shell with some additions. It states:

• plant name or manufacturer's trademark
• product brand (designation)
• GOST or TU
• Date of issue
• number of segments with their length
• drum number
• conductor weight
• conformity mark
• OK mark.

If you come to buy a cable for wiring in an apartment in a whole bay of 100 m, you will receive a tag along with it. But if they cut off a piece for you, they won’t give you the label, you can just look at it.

8. Certificate

Needed to confirm that the cable is of high quality. Typically, products have 2 documents - a certificate of conformity, which is responsible for the suitability of the cable as an electrical installation material, and a certificate fire safety. You can ask the seller for them to review. Documents must be filled out indicating GOST standards for the cable and have a valid period, for example, until the end current year. As a rule, the documentation indicates specifications ( technical specifications) according to GOST and for cable products this is equivalent to compliance with GOST.

9. Condition

This appearance power wire. Pay attention to how the cable looks, because bruises, strong kinks, and compression hide an internal defect. The veins may be broken and even shorted to each other. It is clear that such material cannot be laid, therefore, do not be lazy to inspect the cable in the store, even before paying for your own purchase.

What cable is needed for wiring in an apartment?

We have already said that electrical wiring in an apartment “requires” 2 cable sections.

For sockets you need to take a cross section of 2.5 mm 2, because the switched load can reach 3-4 kilowatts. And a cable of two and a half “squares” is designed for a maximum power of up to 5.9 kilowatts and a current of up to 27 Amperes. This does not mean that you need to “load” the cable line to its limit. The choice always comes with a margin of one third of the planned load. Moreover, the cable lying under the plaster is cooled less efficiently and this is also taken into account when selecting.

For the lighting circuit, a cross section of 1.5 mm 2 is used. The load here is much less, but even if you decide to arrange illumination in the apartment, there will be plenty of current and power reserves.

Important information! Since modern electrical safety rules require grounding household electrical appliances and installing special sockets, then a three-core cable is used for installation. In which there is a working phase conductor, a working zero and a protective zero.

Which cable does the online store website recommend for hidden wiring in a house or apartment?

Let us remind you that the marking contains the main characteristics of cable products. Letter designations indicate the materials of conductors, insulation, sheathing and flexibility, digital designations indicate the number of conductive conductors and their cross-section.

VVG cable

The most common domestic cable for electrical installation in an apartment. It has single-core copper conductors, insulation and a sheath made of PVC plastic, and is used in rooms with normal and high humidity. Designed for voltages up to 660 Volts. Refers to flexible, unarmored power cables. It can include from 1 to 5 cores, with a cross-section from one and a half to 240 “squares”. The conductor shape is round, flat or triangular.

VVG cables are available in several modifications:

• VVG - basic type with vinyl insulation and sheath;
• VVGng is a non-flammable power wire, the insulation of the cores is self-extinguishing, that is, combustion does not spread;
• VVGng-LS - also has self-extinguishing non-flammable core insulation (ng) and a low smoke emission sheath;
• VVGng FR-LS - in addition to non-flammability and low smoke emission, this type of cable received additional fire protection from mica tape.

All brands with the ng prefix can be mounted in bundles, that is, several cable lines can be laid in one corrugation, pipe or pit.

For sockets	For switches
VVGng 3x2.5	VVGng 3x1.5
VVGng-LS 3x2.5	VVGng-LS 3x1.5

Conventional VVG is cheaper, but is not suitable for bundle laying and the shell is less fire-resistant and smoke-resistant. And the VVGng FR-LS brand is professional and is used in conditions of increased fire hazard in enterprises and is much more expensive.

NYM cable

European standard copper cable developed in Germany. Produced in Russian factories and complies with EU standards and GOSTs. The design is similar to the VVGng cable, rated voltage 660 V. Single-wire multi-core NYM cable with a cross-section of 1.5-10 mm2 and multi-wire with a cross-section of 16 mm2 are available. The number of cores is 1-5, the insulation and sheath are made of PVC, non-flammability is provided by the rubber filler between the core insulation and the cable sheath.

Note! In stores you can find cheap cables marked NUM. This “typo” says that this is a copy with reduced characteristics. By purchasing it, you risk receiving low-quality products. We advise you to refrain from dubious savings on security.

VVGng and NYM cables have similar characteristics and advantages of use:

• High quality performance. The cores, insulation, and sheath comply with GOST and this makes the cable reliable.
• Convenient installation and easy cutting. The round cable is easy to install due to the absence of twists and is easier to seal when inserting.
• High fire resistance and safety. Compliance with standards ensures safe work cables under load, and special insulation allows them to be laid in bundles, without the risk of fire from mutual heating.
• Self-extinguishing and low smoke. The shell material is self-extinguishing and slows down combustion. It also provides low smoke without dangerous halogens. If the protection works slowly, the damage from the fire will be minimal.
• Wide range of options in brands at a price to suit any budget.

Which wire is not suitable for wiring in an apartment?

And one more important point. We understand that for most people, “wire” and “cable” are synonymous. In fact, these are different types of cable products. The main difference is that the cable always has a very strong two-layer insulation, with the first layer on top of the conductive cores and the second covering the entire bundle. Even if the cable has one core, the insulation is always double. The wire is a weaker structure with light insulation.

Note! Wiring your apartment with wire, even stranded or stranded, is a very bad idea.

The main problem with wires is their poor resistance to prolonged heating under constant load and their high flammability. Therefore, they do not comply with the requirements of the PUE for wiring in residential premises.

PVS wire

PVS

This is a copper connection wire with vinyl insulation and sheath. Used to connect household electrical appliances to the home network and to make extension cords. The number of conductors is 2-6, the core design is multi-wire, cross-section 0.75-10 mm2. Designed for a voltage rating of 380 V.

Attention! There is no need to take PVS wire for wiring on the advice of friends or to save money.

• Firstly, PVA have a multi-wire core structure. This means that all ends for connection must be tinned and soldered. It takes a lot of time and requires high quality processing of cores and extensive experience of the electrician.
• Secondly, the multi-wire construction of the core is a factor of increased fire hazard. Such a wire heats up more, which means the insulation wears out faster, which is dangerous and can result in a short circuit.
• Thirdly, the PVS wire cannot be laid in a bundle, like a cable. Only with the distance between the threads. That is, ditch the walls for each line separately.

So, the savings are very dubious and symbolic. The low price of the wire will be “eaten up” by the high cost of installation. And the quality of the wiring leaves much to be desired.

ShVVP and PVVP wire

ShVVP, PVVP

Installation cords or cables with single and multi-wire copper conductors. Used to connect electrical equipment and household appliances. They have a short service life; the stranded type requires processing of the ends and soldering during installation. They are not suitable for fixed wiring due to the lack of non-flammable insulation and poor characteristics.

Wire PUNP

Attention! PUNP has been banned for use for wiring since 2007 due to its unreliability.

Although there are “craftsmen” both among clients and among would-be electricians who use it. Motivating this by the fact that “all old apartments have this one.”

But “citizens” forget that since the times of the USSR, the equipment of household electrical equipment has changed greatly and its power has increased. That’s why PUNP was banned - it is low-power, has poor insulation and does not support modern loads.

cable VVGng FR-LSNYM cable

The online store site offers only high-quality cables for electrical wiring in an apartment or house. Full list brands and types in the section:

Come in and choose your cable!

And also ask any questions. Funny and naive first of all! They are the most correct! Because it’s better to make electricians laugh than firefighters, wouldn’t you agree?

We always answer questions and talk about all the intricacies of installation. We quickly select full set for installing apartment wiring from cables to sockets and switches. We take into account your wishes and budget.

Call and ask! Phones

The modern industry producing electrical products is ready to offer consumers a huge assortment of cable products. Each type electric cable or the type of wire is used to solve a specific professional task of electrifying a facility. Any person who decides to install electrical wiring on a personal summer cottage, in his own city apartment or private house will soon understand that copper conductors are most often used for such work and aluminum conductors are much less often used. There are simply no other options, although there are quite a lot of metals with low current resistance.

Why copper and aluminum? Yes, everything is very simple! These are the cheapest non-ferrous metals, optimally suited for the production of wires due to their technical and design characteristics. Of course, it is quite possible to make a cable from gold, but the price of this product will be prohibitive!

Cable products and wires for installation electrical wiring in residential and other facilities are divided into several types and types: powerful power cables, special self-supporting cables, electrical wires for hidden and open wiring, installation conductors and so on.

The range of basic characteristics of such electrical products is varied. All cable electrical products are divided into categories not only according to their purpose, but also according to the type of insulating layer, the structure of current-carrying conductors and the metal from which they are made, design features and other parameters. This article will discuss the main types and types, technical parameters and other characteristics electrical wires and cables that are used when performing work on installing electrical wiring and connecting private houses, apartments, cottages and other real estate to power networks.

Attention! Choosing the right electrical cable or wire is a very important matter, on which the safety of your property and your own health depends. Therefore, for those who do not want to face such catastrophic events as a short circuit, fire or electric shock, we recommend that you carefully select electrical products that meet the requirements of the Electrical Installation Code (PEU).

Power cables

A power cable for power lines is a single-core or multi-core electrical product designed to supply electrical energy to stationary consumers, such as a private house, apartment, cottage or mobile equipment. The power cable connects the main distribution panel or power line to the end user. Regardless of the field of use and technical characteristics, its design consists of the following mandatory elements, which are its basis:

• one or more metal conductors designed to transmit current;
• an insulating layer that provides protection for conductive elements;
• outer sheath, which serves to protect the entire cable structure as a whole.

In addition to these main structural parts of power cable products, they can include a variety of additional elements, such as external belt insulation, a shielding layer, and armor with a cushion under it. The design of the power cable depends on its purpose, scope of use and operating conditions. All these factors are reflected in the color markings and names of the products.

Important! When choosing a power cable, it is necessary to take into account many factors: operating conditions, type and type of installation, as well as compliance with PES standards. This is because various brands Cable products have both advantages and disadvantages that need to be taken into account when purchasing.

Power cable - marking features

Properties and design features power cables, as well as the scope of application are determined by the marking of cable products. Today, there are two types of marking of such products: color or letters. IN Russian Federation alphabetic is used, where each character and its location has a specific meaning. The first character indicates the material of the core and if it is “A”, then it is made of aluminum, and if there is no letter, then it is made of copper. The table below shows the order of marking signs, their letter designation and decryption.

Sign number in the marking power cable	Purpose of the symbol	Decoding the symbol
1	Current-carrying material	A - aluminum No sign - copper
2	Insulating layer material	B - polyvinyl chloride C - impregnated paper NR - non-flammable rubber P - thermoplastic polyethylene
3	Type of outer sheath	C - lead alloy A - aluminum alloy O - separate sheath for each core P - polyethylene or polymer B - polyvinyl chloride
4	Armor protection	B - two coated steel strips BN - the same with non-flammable coating BBG - profiled steel strip K - round galvanized wire P - the same with flat wire
5	Shielding	E - copper over an insulated core EO - common copper for three cores d - water-swelling tape ha - polymer-aluminum tape
6	additional characteristics	ng - does not light ng LS - does not burn, low smoke emission G - flexible cable

If any of the elements are missing from the marking, it means that it simply is not on the power cable. Let's say you don't see the armor designation, which means it's missing. The presented letter marking is relevant not only for power cables, but also for other types of wires, with minor changes and additions. Below we will look at the main and most popular brands of power cables produced by the electrical industry.

VVG cable

The main purpose of the VVG power cable is the electrification of facilities with a network voltage of up to 1 thousand volts. This brand is especially popular for indoor electrical wiring. If you refer to the marking table presented above, then VVG is a copper cable with core insulation made of polyvinyl chloride and external insulation in the form of a cambric made of the same material, and the letter “G” indicates that it is flexible. The number of cores of the product can be from two to five. The service life of these products can reach over 30 years.

The VVG power cable is produced in different versions: AVVG - with current-carrying conductors made of pure aluminum, VVGng - in a protective casing made of fire-resistant material, VVGp - product flat look and others. The color of the external insulation for most products is black, and each core has its own color scheme, corresponding to the marking according to the standard: yellow with a green stripe for PE conductors, blue or white with a blue stripe for N cores, and absolutely white for phase cores. The VVG power cable almost completely corresponds to its imported analogue, produced according to the foreign DIN standard, the technical parameters of which are presented in the following section.

NYM cable

NYM power cable is used for installation work when laying lighting and power networks in both residential and industrial premises. The maximum voltage at which this product can be used should not exceed 660 volts. The cable can be used in open spaces, but it should be taken into account that its insulation is subject to destruction under the influence of sunlight. Therefore, the NYM cable must be protected with a special corrugation or other protective sheath. Main feature This product is that it is equipped with a special filler inside the outer shell, which ensures complete sealing of the cores.

Unlike the domestically developed VVG power cable, NYM wire is produced only in a round version with solid copper conductors. This fact gives it an advantage in conventional electrical installation, but it is very inconvenient to install it in hidden wiring grooves. In all other respects, the NYM cable is a complete analogue of the VVG. The external and internal insulation of the product is made of heat-resistant PVC (polyvinyl chloride). Its color for the outer sheath is mainly black, and the insulation of the current-carrying conductors has the following colors: black, yellow with a green stripe, brown, as well as gray and blue. In Russian, the product does not have a letter designation.

SIP cable

Power is a self-supporting electrical wire with reliable core insulation, the very name of which speaks of its specific properties. Its main feature is that it can withstand large mechanical loads. In addition, the insulating layer of the product is made of stitched polyethylene, which withstands exposure to sunlight and high humidity. Based on these properties, SIP is excellent for installing power lines in open spaces and branches from them for the electrification of various objects, such as residential, as well as small industrial and commercial. This type of cable products is gradually displacing from the market aluminum wires without insulation of grades “A” and “AC”, which were widely used for laying overhead power lines in the recent past.

Available only with pure aluminum cores, which do not have an additional common insulating layer. The cross-sectional area of ​​the product conductors can be from 16 to 150 square meters. mm. The marking of this cable is not directly related to the number of current-carrying wires. For example, SIP-1 is a three-core cable, the neutral current-carrying conductor of which is also load-bearing. The designated product number encrypts all information about the product. SIP power cable is a rather specific cable product. When installing it, it is necessary to use special fittings: specialized anchor brackets, special clamps for connection, and so on. Without these additional elements it is impossible to carry out installation work.

Cable VBBShv

This product refers to power cables with armor and current-carrying conductors made of copper, which are produced in both monolithic and stranded versions. The cable design can consist of from 1 to 6 current-carrying cores, each of which is enclosed in its own PVC insulation, and on top they are covered with a common sheath of the same material. The cross-sectional area of ​​the conductors ranges from 1.5 to 240 square meters. mm. The main feature of VBBShv is the presence of an armor layer made of two steel strips between the outer protective shell and the current-carrying conductors.

This cable is designed to operate over a wide temperature range from -50 to +50 °C with humidity environment up to 98%. The insulation of the product is resistant to moisture and aggressive environments. Armored cable VBBShv is intended for installation of electrical networks both underground and outdoors in protective sheaths to eliminate the negative effects of sunlight. VBBShv can be operated in networks with a maximum AC voltage of up to 6 thousand volts.

Attention! At the top of the article, we looked at the most common types of power cables that are present on the modern market. In addition to these products, for the full installation of electrical networks it is necessary to use another type of electrical products, which can be called electrical wires, although this is a purely conditional division. Below we will look at non-power cables, wires and cords intended for electrical wiring and other purposes.

Types of electrical wires and cords

For many consumers, the terms cable and wire are synonymous, but this is not entirely true. A cable is a complex electrical product, usually with several layers of insulation and a separate sheath for current-carrying conductors. Electrical wires and cords are much simpler in their design characteristics. Most often they have one layer of insulation, rarely two, and sometimes they are produced without an insulation layer at all. The purpose of these two types of products is also different. The cable is designed to transmit high power current. The wires are used in networks and devices with a voltage of no more than 380 V, although they can withstand higher values.

Among the variety of such products, the following brands have gained the greatest popularity among consumers: PBPP, PBPPg, APUNP, PPV, APV, PVS and ShVVP. These electrical wires are used for various purposes: installation of internal electrical networks, connecting devices and equipment, grounding and in many other cases. Below we will look at the design features and areas of application of these most popular brands of electrical products today.

PBPP wire

This is a flat electrical wire with two or three solid copper cores. The outer protective layer and conductor insulation are made of PVC. The cross-sectional area of ​​the conductors is from 1.5 to 6 square meters. mm. The operating temperature of the product is from –15 to +50 °C with a network voltage of up to 250 V. The electrical wire PBPP (PUNP) is used when installing lighting systems and power outlets. There are modifications of this product: PBPPg and APUNP. The letter “g” in the marking means that this wire is flexible and its current-carrying conductors are multi-wire. The modification with the first letter “A” is a wire with aluminum conductors.

PBPP wire has become very widespread, as it is excellent for connecting lighting, installation electrical outlets and switches, as well as for solving other electrical problems. This product is truly a universal conductor. electric current, which is highly popular due to its excellent quality. The PBPP wire is recommended for use during electrical installation work in a private house, apartment or country house.

Important! Basically, PBPP brand wires of all modifications are used in home and household networks. They are great for installing indoor wiring, but should not be used as a replacement for power cables. When purchasing these products, be careful, as mislabeling of wires of these brands is quite common!

PPV and APV wire

PPV wire is a flat electrical product with monolithic copper cores in PVC insulation with jumpers between the conductors. The number of current-carrying conductors is two or three with a cross-sectional area from 0.75 to 6.0 square meters. mm. The operating temperature range of the product is from –50 to +70 °C with a network voltage of up to 450 V and air humidity of up to 100%. The wire can be used in lighting networks, as well as in power lines. A modification of this electrical product is the APPV electric wire with aluminum cores.

APV is the most popular aluminum wire with one core in PVC insulation round shape with a cross-sectional area from 2.5 to 16 sq. mm for a monolithic core and from 25 to 95 sq. mm for stranded. Moisture-resistant, has increased strength and is resistant to any mechanical loads.

PVS wire

PVA cord is the most popular electrical product designed for connecting lighting equipment, household appliances and other devices that consume electricity to electrical networks. The wire structure is multi-core, containing from 2 to 5 conductive copper conductors. The cores of the product are multi-wire, which gives it excellent flexibility. They are covered with an insulating layer of PVC and placed in a molded sheath of the same material, which hermetically fills the internal volume between the cores.

PVA wire is round with a dense texture. The cross-sectional area of ​​the conductors is from 0.75 to 16 square meters. mm. The mains voltage is up to 380 V, and the operating temperature is from –20 to +40 °C. The shell of the product is usually white, and the insulating layer of the current-carrying conductors is colored. Due to its exceptional flexibility, PVA cord has high resistance to mechanical bending loads. A modification of the product marked PVS U is designed for use in low temperatures down to –40 °C.

Recommendation! PES standards do not prohibit the use of a PVA cord for laying hidden electrical wiring, organizing grounding and connecting electrical outlets. But if you decide to use this wire specifically for such purposes, then you should know that it cannot be used in open space and, of course, laid in the ground.

ShVVP wire

The SHVVP cord is designed for connecting household appliances and devices to electrical network. Its main function is a cord for connecting low-power equipment through an outlet to the network. The shell of the product is made of ordinary vinyl, and the insulating layer of each current-carrying core is made of the same material. Current conductors are multi-wire, copper with a cross-sectional area from 0.5 to 0.75 square meters. mm., there are two or three of them. The cord insulation does not have high strength, so it is better not to use it under high loads. The ball screw is flat in design, the shell is absolutely white or black, the insulation of the current-carrying conductors is colored. Operating temperature from –25 to +70 °C.

In addition to connecting low-power household appliances and making simple extension cords, the ShVVP cord is often used in control and automation systems to power low-current circuits. The flexibility of the product is a very important parameter, which allows the wire to be used in a variety of areas. In addition, SHVVP is resistant to aggressive environments and can withstand air humidity up to 98%, making it moisture resistant.

Important! The cross-sectional area of ​​wire strands for installing electrical wiring and connecting household appliances depends on the strength of the current flowing through them when maximum load. This value must be calculated and the conductor with the nearest larger cross-sectional area must be selected.

Conclusion

In this article, we examined the main types of cables and wires for transmitting electrical energy both in everyday life and on other real estate objects. Of course, this is only a small part of the entire range of cable and wire electrical products, but the most popular on the market. It is simply impossible to list all the types and types of wires and cable products in the limited space of the article, but the most popular brands, their markings and specifications you now know what will certainly help you when choosing such products!

Video on the topic

In fact, all these electrical products are created to perform a common task: transmitting electricity from a voltage source to a consumer. They must perform their functions for a long time and reliably without creating emergency situations and malfunctions.

Wires and cables work in all branches of practical human activity, when it is necessary to create a closed circuit for the passage of electric current and eliminate its loss through unexpected leaks.

Due to the similarity of the issues being solved, many simple people their differences are not distinguished; they are classified into one category.

However, cables, wires and cords operate under different operating conditions and are used on various areas electrical mains differ in purpose. Therefore, they have different internal structure and design.

In electrical transmission lines, there are cases where electrical power is transmitted sequentially through overhead wires and cable, as shown in the photo below.

A cable branch on an overhead power line is created to perform specific tasks required by local conditions.

Electric wire

Compound

It has the simplest design, consisting of two parts:

1. a metal core that serves to create a path for electric current;

2. a layer of insulation that prevents the flow of currents in an undesirable direction.

Insulation functions can be assigned to the air surrounding the metal, and not to a special shell of polymers and dielectrics. In this case, the wire core is made bare, and the contact points of the wires with the fastening elements to load-bearing structures create with dielectric properties. They are called insulators.

Materials for the conductive core are most often created on the basis of:

copper and its alloys;

aluminum

A promising design is considered to be a composite one, created for effective use the best performance characteristics of the above metals.

To solve specific problems, conductive cores made of steel alloys, nichrome, other metals and even silver or gold can be used.

Core design

It can be created from:

1. a solid conductor of a certain length;

2. or twisted from thin wires working in parallel. Solid wires are easier to manufacture. They are the most rigid, used for transmitting electrical energy when mounted in a stationary manner, and transmit direct and low-frequency currents well.

Stranded strands are more flexible and work better at high frequencies.

Typically, the term wire refers to a product made from a single wire. In fact, they can be twisted or mounted with multiple strands. Examples include double telephone wires of the “noodle” type and other designs.

All of them are designed to work in light operating conditions and in most cases require additional mechanical protection from external influences.

Electrical cable

Its more complex design is created to ensure reliable operation when exposed to destructive environmental factors.

The number of current-carrying cores is determined by operating conditions. They are insulated among themselves by various dielectric layers. Additional cable elements can be:

protective outer shell made of plastic, steel or wire armor;

aggregate;

core;

Each of these parts performs protective functions for specific conditions.

The main groups of cables for electricians are:

power, operating in electrical installations up to and more than 1000 volts;

control rooms transmitting status information various elements systems;

controls used to transmit commands entered manually or by automatic systems;

communications based on the exchange of signals of different frequencies.

A separate group includes special purpose cables:

radiating, used for transmitting high-frequency radio signals;

heating, converting electrical energy into heat.

Conductors

They are made according to the same principles as wires. They can be created from different materials with a stranded or solid conductor. Covered with a dielectric layer.

Based on the degree of flexibility of cable design, they are divided into seven groups. The difficult-to-bend category No. 1 includes monocore. The most flexible and, accordingly, expensive is No. 7.

During installation, stranded wires of flexible cables are connected through special tubular lugs called terminations. There is no need to install them on a monocore.

Shell

Protects conductors and their insulation from mechanical damage, seals them from the penetration of moisture and foreign impurities. May contain reinforcing and shielding layers.

The most common shell materials are:

plastics;

• reinforced rubber grades;

Plastic materials can perform the following tasks:

1. provide an insulating layer with high dielectric properties;

2. create a sealed hose that protects the structure placed in it;

3. serve as a screen through the use of semiconductor properties.

Impregnated cable paper is used in high-voltage products up to 35 kV inclusive.

Cross-linked polyethylene is used to ensure the dielectric properties of cables operating in electrical installations with voltages up to 500 kV with high reliability and durability.

For high-voltage circuits 110÷500 kV inclusive, until 2005, oil-filled cables were produced, consisting of shielded conductors mounted inside a sealed sheath with oil. With the massive introduction of insulation based on cross-linked polyethylene, their design has lost its relevance.

Safe working conditions

All cable products are assessed for:

1. behavior during a short circuit in the cable channel;

2. ability to withstand long-term overloads;

3. spread of open fire at high heat;

4. release of toxins during combustion.

Short circuit danger

When a short circuit occurs between the wires, a temperature of up to a thousand degrees is created. It is transmitted to nearby cables with small losses, heats them up, and can involve them in combustion. The resulting gases create high pressure, which depressurizes the cable channel and provides an influx of fresh air with oxygen, which supports the development of the fire.

Long-term overloads

Excessive currents heat up the metal of the conductor and the insulation layer with the sheath. Under the influence of extreme temperatures, chemical reactions decomposition of the insulation layer, gases are released. They begin to mix with air and ignite.

Spread of combustion

A conventional shell made of PVC plastics and certain types of polyethylene can transmit the combustion process further, which contributes to the development of fires. A particular danger is created when cables are installed vertically.

According to this indicator, cable products are divided into:

• flame retardant in a single gasket: vertically and horizontally;

  flame retardant in group laying: vertically and horizontally;

  fire resistant.

The main indicator of this process is specific heat combustion of electrical wiring or cable line, determined experimentally.

Ability to release toxic substances

This takes into account the reaction of the cable sheath to an external fire affecting its structure. Insulation compounds, even non-flammable, can release dangerous toxins when exposed to significant heat.

Such cables are prohibited from being used in places with large crowds of people in subway transport and similar facilities.

Requirements for cable products

To improve operational reliability and safety, modern cables are rated by:

fire resistance;

resistance to dielectric heating and fire resistance;

methods of cutting ends - ending;

protection against moisture penetration.

Each of these parameters has analysis methods and criteria for evaluating the results obtained.

Electrical cord

Its design is somewhere between an electrical wire insulated with several cores and a cable. It is created by special technological methods to impart properties of increased flexibility, providing long-term operation when creating frequent, numerous bends.

Purpose of the electrical cord: providing connections between the voltage source and mobile electrical appliances.

To highlight the neutral or middle conductor, use a light blue color. Phase conductors are usually designated in black, brown and gray.

The marking methods given as examples reflect the principles for determining the design of cables and wires. But they don't contain full list all information about them, which is published in detail in special reference books.

During the development of local networks, quite a lot of types of cables have appeared, and all of them are the result of increasingly complex standard requirements. Some of them are already a thing of the past, and some are just beginning to be used, and thanks to them, it has become possible to achieve the high data transfer speed that we need so much.
In today's article I will talk about main types of cables And connectors, which have become widespread in the construction of wired local networks.

Coaxial cable

Coaxial cable- one of the first conductors used to create networks. Coaxial cable consists of a central conductor enclosed in thick insulation, a copper or aluminum braid and an outer insulating sheath: To work with coaxial cable, several different types of connectors:

Installed at the ends of the cable and used to connect to the T-connector and barrel connector. . It is a kind of tee that is used to connect a computer to the main line. Its design contains three connectors at once, one of which is connected to the connector on the network card, and the other two are used to connect the two ends of the trunk. . With its help, you can connect the broken ends of the trunk or sharpen part of the cable to increase the radius of the network and connect additional computers and other network devices. . It is a kind of stub that blocks further propagation of the signal. Without it, the functioning of a network based on coaxial cable is impossible. A total of two terminators are required, one of which must be grounded.

Coaxial cable is quite susceptible to electromagnetic interference. Its use in local computer networks has long been abandoned.
Coaxial cable has become mainly used to transmit signals from satellite dishes and other antennas. Coaxial cable received a second life as a backbone conductor of high-speed networks that combine the transmission of digital and analog signals, for example, cable television networks.

twisted pair

twisted pair is currently the most common cable for building local networks. The cable consists of pairs of intertwined copper insulated conductors. A typical cable has 8 conductors (4 pairs), although cables with 4 conductors (2 pairs) are also available. The colors of the internal insulation of conductors are strictly standard. The distance between devices connected by twisted pair cable should not exceed 100 meters.

Depending on the presence of protection - an electrically grounded copper braid or aluminum foil around the twisted pairs, there are types of twisted pair:

Unshielded twisted pair (UTP, unprotected twisted pair). Apart from conductors with their own plastic protection, no additional braids or grounding wires are used: Foiled twisted pair (F/UTP, foil twisted pair). All pairs of conductors of this cable have a common foil shield: Shielded twisted pair (STP, protected twisted pair). In a cable of this type, each pair has its own braided shielding, and there is also a common mesh screen for all: Screened Foiled twisted pair (S/FTP, foil shielded twisted pair). Each pair of this cable is in its own foil braid, and all pairs are placed in a copper shield: Screened Foiled Unshielded twisted pair, unprotected shielded twisted pair). Characterized by a double shield of copper braid and foil braid:

There are several categories of twisted pair cables, which are marked from CAT1 before CAT7. The higher the category, the higher quality the cable and the better performance it has. Local computer networks of the Ethernet standard use twisted pair cable of the fifth category (CAT5) with a frequency band of 100 MHz. When laying new networks, it is advisable to use an improved cable CAT5e with a frequency band of 125 MHz, which better transmits high-frequency signals.

To work with a twisted pair cable, an 8P8C (8 Position 8 Contact) connector is used, called RJ-45:

Fiber optic cable

Fiber optic cable– the most modern data transmission medium. It contains several flexible glass light guides protected by heavy plastic insulation. The data transfer speed over optical fiber is extremely high, and the cable is absolutely free from interference. The distance between systems connected by optical fiber can reach 100 kilometers.

There are two main types of fiber optic cable - single-mode And multimode . The main differences between these types are associated with different modes of passage of light rays in the cable. There are many connectors and connectors used to crimp a fiber optic cable. different designs and reliability, among which the most popular are SC, ST, FC, LC, MU, F-3000, E-2000, FJ, etc.:
Application of fiber optics in local networks limited by two factors. Although the optical cable itself is relatively inexpensive, prices for adapters and other equipment for fiber optic networks are quite high. Installation and repair of fiber optic networks requires high qualifications, and cable termination requires expensive equipment. Therefore, fiber optic cable is used mainly for connecting segments of large networks, high-speed Internet access (for providers and large companies) and data transmission over long distances.