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Yellow green stripes. Color marking of wires and cables

Wiring in buildings consists of insulated aluminum and copper wires. For convenient wiring, as well as for further cable maintenance, manufacturers use different colors to mark current-carrying cores in an electric cable.

Mounting wire

What colors are found

According to the Electrical Installation Rules (PUE), the insulating wiring material must have a color and be easily recognized by the master. The electrical cable usually has a three-core structure (phase, zero, ground), each wire is painted in a certain color. Now it is hard to believe that not so long ago the insulation of cable cores had only two colors: black and white. But, fortunately, with the introduction of new rules, the color design has changed dramatically. Basically, the following colors are used for electrical wiring: white, black, red, blue (blue), yellow-green, brown shades. Let us consider in more detail which conductor corresponds to a particular color.

An illustrative example of colors for electrical conductors.

neutral

The neutral conductor (neutral) is usually blue or blue. In the junction box, this wire is connected to the zero bus, which is marked with the Latin letter N. All blue wires are connected to this bus. It should be noted that the zero wire combines two functions: working and protective zero. The protective wire zero is also blue, and at the ends, i.e. at the joints, there are yellow-green stripes. Connects to the bus marked REN. It should be noted that generally accepted rules allow green stripes throughout the wire with blue terminations.

Scheme of a closed electrical circuit.

Ground wire

The ground conductor is yellow or green, or marked with stripes of that color throughout the cable. Such a conductor is connected in the switchboard to the ground plate. In the junction box, the ground conductor is connected to ground wires coming from sockets and electrical appliances, such as lamps, for example. The earth conductor is not connected to the residual current device.

What does the ground wire look like?

Wire phase

The core responsible for the phase in the electric wire is painted in different colors. It can be: black, brown, red, gray, purple, pink, white, orange, turquoise. Each manufacturer of electrical wires has the right to designate a phase conductor in one of these shades. Simply put, the main task of an electrician during the installation of the wiring of the room is to first determine the neutral wire and the ground wire, and the remaining wire will be the phase. In order to avoid electric shock, an electrician must check the wires with a special probe, most often it is presented in the form of a screwdriver.

What color are the wires in the cable?

How to color-code wires yourself

There are times when the wires have a non-standard color that differs from those listed in the PUE. In such situations, you can independently color-code the cable cores. To do this, we use colored electrical tape, which we mark the ends of the wires in the switchboard. Also for such purposes there is a special heat shrink tube, it is sometimes called cambric. After that, do not forget to write down your designations so that there is no confusion in the future.

Colored electrical tape to identify wires.
Heat shrink tube for wire insulation.

Video. What does a junction box look like in a residential area. How the color marking of wires has changed since the times of the USSR

Comments:

Colors of tires and wires for three-phase alternating current.

At power plants and substations in three-phase networks, high-voltage wires and tires are painted in this way: phase "A" - yellow; phase "B" is green and phase "C" is red.

What is the color of the "+" and "-" wires in the DC network:

In addition to AC networks, DC circuits are also widely used. DC circuits are used in:

1. In construction, when using forklifts, electric trucks and electric cranes, as well as in industry.

2. In electric transport - trams, trolleybuses, electric locomotives, motor ships, etc.

3. At electrical substations - to supply energy to automation.

In a DC network, only 2 wires are used, since in such networks there is no phase or neutral conductor, and there are only positive and negative buses (+ and -).

According to regulatory documents, wires and tires with a positive charge (+) are painted red, and wires and tires with a negative charge (-) are marked in blue. The blue color indicates the middle conductor (M).

The positive conductor of a two-wire network is marked with the same color as the positive conductor of the three-wire network to which it is connected, only if the two-wire DC network is created through a branch from the three-wire DC network.

The color of the wire in the wiring: earth, phase and zero.

To eliminate confusion and simplify installation work when laying AC power networks, use multi-core wires in multi-colored insulation.

Color coding of wires it is especially important when wiring is done by one person, and maintenance or repairs are done by another. Otherwise, he will have to constantly check where the phase is, and where is zero with the help of a probe. Those who have worked with old wiring know how annoying it can be, because before in everyday life there was only white or black insulation. Since the days of the USSR, the color designation of wires has constantly changed until a special standard was defined. Now each color of the conductor defines its purpose in the wire.

At present, the normative document is PUE 7, which regulates the color marking of insulated or non-insulated conductors, where, according to GOST R 50462 “Identification of conductors by colors or digital designations”, only certain designations and colors should be used.

The main purpose of marking electrical wiring is the ease and speed of determining the purpose of the conductor along the entire length, which in fact is one of the main requirements of the PUE standards.

Below we will consider what colors the conductors of AC electrical installations should be, with voltages up to 1000V and with a grounded neutral (for example, wiring of administrative buildings or residential buildings).

Colors of zero working and zero protective conductor.

Zero working conductors (N) are indicated in blue. Zero protective conductor (PE) is marked with yellow-green transverse or longitudinal stripes. This combination must necessarily be used exclusively for marking earthing conductors.

Combined zero working and zero protective conductors (PEN) - blue color along the entire length of the cord with yellow-green stripes at the junctions or at the ends. It is important to mention that GOST today allows the reverse coloration, that is, yellow-green stripes with blue at the junctions.

To summarize, then wire color should be distributed like this:

1. Combined (PEN) - yellow-green with blue marks on the ends;

2. Zero working (N) - blue (blue) color;

3. Zero protective (PE) - yellow-green.

Colors of phase wires.

According to the PUE, when marking phase conductors, preference should be given to the following colors: turquoise, black, orange, brown, white, red, pink, gray or purple.

It is known that a single-phase electrical circuit can be created by branching from a three-phase circuit, in which case the color of the wire of the phase of the single-phase circuit must match the color of the phase conductor of the three-phase circuit.

Color designation of the insulating coating of conductors must be carried out in such a way that the color of the phase conductor is easily distinguishable from the color of the N, PE or PEN conductors. In the case of using an unmarked wire, colored identifiers are placed at the junctions or at the end.

In electrical installations and household electrical networks, conductors are used for various purposes. The main ones used for the transmission of electrical energy are phase voltage conductors, zero working and zero protective.

All of them must be identified. Otherwise, even if there are circuit, wiring or single-line diagrams explaining which contacts of electrical devices they are connected to, it will be impossible to figure it out. And the need for this arises constantly.

Another important reason requiring the identification of conductors is electrical safety. Touching any live parts, even those not under a life-threatening potential, is prohibited without checking the absence of voltage on them. But sections of the circuit containing both dangerous and safe potentials must be clearly marked. This is one of the many components of the organization of the safe operation of electrical installations.

Identification of conductors of power electrical circuits is carried out by two methods:

conductors are painted in colors corresponding to their purpose;
at the ends of the conductors or along their entire length, letter designations are applied that unambiguously determine the functional purpose.

The rules for applying color and letter marking to conductors used in power electrical circuits are detailed in GOST R 50462-2009. Despite the fact that it has the status of the national standard of the Russian Federation, it completely repeats the IEC 60446-2007 standard. Thus, the rules for marking wires in Russia are brought into line with European standards. The relevance of this is dictated by the fact that Western equipment is supplied to Russia, manufactured according to European standards, and therefore, for its correct operation, our own rules must be brought into line with IEC.

So, now let's figure out what colors the wires and cable cores are for use in various circuits.

Marking of phase conductors

All electrical networks can be divided into:

single-phase;
three-phase;
DC networks.

Each of them has its own rules for marking conductors. Let's start with phase.

In single-phase circuits, all phase conductors according to GOST must be brown. However, this does not mean at all that such wires should be used when installing a single-phase switchboard. Their color may not necessarily be brown, but any, but not blue or yellow-green. Additionally, the ends of the conductors can be marked with the letter L1, L2 or L3, indicating which phase of the three-phase network this shield is connected to.

However, if this single-phase circuit branches off from a three-phase one as part of a device or shield, then the color of its conductors must match the color of the wires of the phase to which it is connected: brown, black or gray.

Brown, blue and yellow-green colors are used for the cores of cables intended for the installation of single-phase networks.

Phase wires in three-phase networks were previously marked with letters: A, B and C. In addition, the tires were painted in the appropriate colors for identification:

phase A - yellow;
phase B - green;
phase C - red.

Now GOST prohibits the use of green and yellow for marking, as they can be confused with yellow-green, which has a different purpose, which will be discussed later.

It was not customary to mark the wires at all. A good example of this is the access switchboards. All the wires in them: both phase and zero are the same. An attempt to determine their purpose is fraught with some difficulties: after all, even to conclude that the conductor is connected to the phase of the mains, it is possible with certainty only when there is voltage on it, and you have an indicator in your hands. You can never be sure that the conductor is zero.

Therefore, GOST for phase conductors prescribes the following marking.

phase wire	Letter	Colour
Phase A (Phase 1)	L1	brown
Phase B (phase 2)	L2	black
Phase C (Phase 2)	L3	grey

It is allowed to mark wires in any of two ways or both at once. In the first case, tags with a letter designation are attached to the ends of the wires, in the second, the corresponding coloring of the current-carrying parts is used. Strictly speaking, it is not at all necessary to use wires that have brown, black and gray colors in switchboards during installation. Color binding is more relevant for cable lines, as their cores are painted in brown, black, gray, blue and yellow-green. When connecting cables to terminal blocks, consumers or to the outputs of electrical devices, it is necessary to comply with the requirements of GOST.

For the assembly of panel products, the installation of phase circuits is allowed to be carried out with single-color wires, while observing the conditions:

blue color cannot be used;
yellow-green color cannot be used;
marking with letters applied to the beginning and end of the wire is required.

Western manufacturers do not paint tires in brown, black, gray, as well as blue and yellow-green, marking them with letter markings. At the same time, the cost of assembling panel products and complete switchgears is slightly reduced. But in return, there is a drawback: in order to find out the purpose of the tire, you need to find the nearest marking plate on it or use the knowledge of the Electrical Installation Code, which indicates the requirements for the relative position of the tires. But there are electrical installations in which the phase sequence cannot comply with the PUE. Therefore, when marking tires, it is necessary to stick the plates as often as possible. GOST prescribes marking at least twice within a panel or shield: at the bus inlet to the panel and at the output, or at its beginning and end.

Marking conductors "ground" and zero

Here, the labeling requirements are much more stringent, as this is directly related to electrical safety.

Protective zero (or earth), as well as live parts intended for the potential equalization system, are marked with alternating yellow and green stripes. For tires, this is a uniform alternation of yellow and green stripes, while wires and cable cores are colored appropriately at the factory.

It is prohibited to use yellow-green, as well as blue for marking other circuits, as well as marking the protective zero with other colors.

For the letter marking of the “ground” wire, the designation PE is provided, for the potential equalization conductor - GNYE.

Working zero is marked using only blue. Other markings, as well as the use of blue for other purposes, are prohibited. Working zero is denoted by the letter N.

It is a little more difficult to mark the zero combined, which is assigned the designation PEN. Since it combines the functions of a ground conductor and a working zero, this is also taken into account when marking. It is permissible to use two methods similar to each other: either take a wire that has a blue color and apply yellow-green markings at its ends, or apply blue markings at the ends of a yellow-green wire. This can be done either with insulating tape or heat shrink tubing.

Busbars for identification do not need to be painted over the entire length, since this method is difficult for these chains. On the tires designed to connect the conductors "ground" and zero, many holes are made for their connection, which makes solid coloring difficult, and at times impossible. It is allowed to apply colored stripes that have blue or yellow-green colors along the edges of the tire.

Almost everyone who has dealt with electrical wiring has noticed that wires in insulation can have a different color. But few people know that this action makes it easier to install electrical wiring, and there are even special rules for electrical installations, following which you can significantly reduce the risk of tragic consequences when working with electricity. So what is the essence of color designations and what they mean - the answers to these questions will be given below.

The main task of marking wire insulation

First of all, the wires are marked with certain colors to ensure safety during work. In assigning a color for each wire, PUE standards (electrical installation rules) and international European standards are applied. Each electrician can easily distinguish, what voltage is(or not) each wire, and also determine where the phase, zero and ground are located.

Of course, if we take the connection to the network of a single-gang switch as an example, it will not be difficult to determine the purpose of each wire without color marking. But if we consider the connection of the switchboard, then here we cannot do without special designations. Indeed, in the event of an incorrect connection of current-carrying parts, a short circuit may occur, the wiring will begin to heat up (and, as a result, a fire will occur), and in the worst case, human electric shock installer or people in the vicinity.

In the modern edition of the PUE, it is proposed to maintain not only a color designation, but also an alphabetic one, which greatly facilitates work in electrical installations.

The concept of phase and zero in electrics

Before considering color coding, you must first understand the concepts of phase and zero in electrical wiring.

Letter designations are used on electrical diagrams.

For the correct conduct of electrical work, it is necessary to impeccably follow the rules for connecting current-carrying parts, respectively, all wires of the circuit must differ markedly from each other. The question becomes reasonable about what color the phase and zero in electricity are indicated. Below are descriptions of each case separately..

Wire colors phase, zero, ground

As mentioned earlier, the coloring of wires in electrics at manufacturing plants is carried out in accordance with the PUE.

Ground wire designation

Ground wire usually denoted by yellow, green and yellow-green colors. Manufacturers can apply stripes of yellow-green color - both in the longitudinal and transverse directions. In addition, lettering is recommended. However, the applied letter marking does not exclude color marking. Color designation, according to the PUE, is mandatory. On the example of a switchboard, this wire is connected to the ground bus, housing or metal door.

Zero wire

Speaking of zero, it should not be confused with grounding. Designated in blue or white-blue. But in some cases, the ground wire is aligned with zero. Then it is dyed green-yellow, and there is always a blue braid at the ends. In both single-phase and three-phase circuits, only one neutral wire is used. This is due to the fact that in a three-phase circuit, the maximum shift of one phase can be 120 °, which allows you to use one neutral wire.

Phase wire designation

Depending on the type of wiring, an AC circuit can be either single-phase or have three phases. Let's consider both of these cases separately.

Single phase wiring

It is used in networks with a voltage of 220 W. Most often, the phase wire is painted black, brown or white, but you can also find other wire markings: brown, gray, purple, pink, orange or turquoise. It is also customary to letter L. This is necessary not only on the diagrams, but also in poor lighting conditions or if the wires were covered with dust.

Due to the fact that it is the phase that poses the greatest danger during work, it is these parts that have the brightest color for quick identification and subsequently more accurate actions with them.

Three phase wiring

It is used in networks with a voltage of 380 W. Previously, all wires and buses in a three-phase network were painted yellow, green and red (G-G-R), which respectively designated phases A, B, C. These designations were difficult due to the similarity yellow-green marking of ground wires. Therefore, according to the PUE, from January 1, 2011, new standards were introduced, where the phases are designated L 1, L 2 and L 3, while each has brown, black and gray colors (K-Ch-S).

On the example of a three-wire wire. Three-core cable wire colors: blue, brown and yellow-green. Brown is phase, blue is zero, and yellow-green is ground.

These were the color options for AC networks.

Coloring of wires in DC networks

In networks with direct current, a different color and letter marking of wires and tires is used. The fundamental difference here is the absence of zero and phase in the usual sense. This wiring uses a positive conductor, indicated in red and a “+” sign, and a negative blue conductor with a “-“ sign, as well as a blue neutral bus, which is indicated by the Latin letter M.

Not all people who carry out work on the installation of electrical networks follow the established marking rules. Therefore, before proceeding with the installation, you should first check the presence of current in the wires with a multimeter or a conventional indicator screwdriver. In the future, mark the wires with the required color using colored electrical tape or special heat crimps. There are also special devices that allow letter marking.

When working with electricity, a large number of cables of different sizes and colors are used. To always select the right product, there is a marking of wires by color. So, individual cables are always marked with the same color for easy use. For example, the color of the ground wire is always made in green-yellow insulation, and the color of the phase is green. This allows you to determine the purpose of the wire without tests and do it with another branch if necessary.

In the event that there are several phases and neutral wires in the network, they are marked with colors in accordance with the set of rules for working with electricity. Usually these are colors that are close to the main color, but depending on the network, they may differ.

electrical safety

Alternating electric current with a voltage of 220 V or 380 V is dangerous for humans. Careless touching of bare wires or metal parts of electrical equipment that may be energized can result in severe burns or death!

For this, the PUE gives an answer not only to the questions: what color is the ground wire, or what is PEN, but what it is for.

grounding;
protective zeroing;
separation of networks by a transformer.

To ensure safe operation in existing electrical installations up to 1 kV, five grounding systems are used: TN-C, TN-S, TN-C-S, TT, IT with different methods of grounding, grounding and network separation.

TN-C, where the working zero N and grounding PE conductors are combined in one PEN wire. It is characterized by: the use of a cable with four cores in a three-phase network and a two-core cable in a single-phase network. This is the oldest electrical network device, still found everywhere, for reasons of economy, for example, in street lighting.
TN-S, where the working N conductor and the grounding PE are separated from the supply transformer to the end consumer. Such networks are made of five-core cables for a three-phase network and three-core wires in a single-phase network.
TN-C-S, where there is one combined PEN conductor of a four-core cable, from the supply transformer to a group panel at the entrance to the building, which is further divided into N and PE, respectively, into five and three-core wiring. This is the most common system for constructing power supply networks for buildings and structures.
TT, where there is only one working N conductor, and only the electrical equipment case is grounded. In such a system, four and two-wire wiring are used, respectively. So, mainly overhead power lines are arranged.
IT, where the electrical installation is separated from the supply network by a transformer and completely isolated from the ground. This is the safest system for humans, it is used for special purpose consumers only.

Thus, the color of the wires phase and zero, L and N in an electrician will help to visually determine the security system used in a given electrical network.

Specificity of different types of cable products

Before talking about marking, it is worth determining what is the difference between a cable, a wire and a cord. Various types of cables can be used not only on the surface, but also underground and in water. This is possible because one or more insulated cores are protected by a special sheath, which can be made from various materials that can withstand aggressive environmental conditions.

As for electrical wires, they also have twisted or insulated wires or cores. They are covered with a protective non-metallic sheath or winding, which does not imply their laying in the ground.

A cord is a wire in which there are flexible and insulated cores. With the help of this type of cable products, various household devices, devices that are mobile or often move from place to place are connected to the network.

Power products. These include SIP and VVG wires. The latter variety is suitable for wiring and lighting indoors, connecting electrical installations. Self-supporting insulated wire (SIP) is used in the construction of overhead power lines and the creation of branches to residential buildings and buildings. The number of conductive cores in products marked VVG varies from 1 to 6. For the SIP variety, this figure ranges from 1 to 4.
The purpose of RF cables is to transmit a signal from one device to another.
Control products are needed to power devices and are indispensable in remote control systems. GOST allows them to have a number of conductive cores from 4 to 37 pcs.
In order to coordinate the operation of instruments and devices at a distance, control wires are used along with the control view. Current-carrying conductors in such products can be from 3 to 108 pcs.
A separate type of communication cable will be required so that subscribers can exchange information at a distance. Within this group, there is a division into high- and low-frequency product types.

Why labeling is needed

Specific colors in electrics are not chosen by chance. Colored wiring is necessary for safe electrical work to avoid short circuits and electric shock. Previously, the color of the conductors was black or white, as a result, this brought great inconvenience to electricians.

When disconnecting, it was necessary to supply power to the conductors, after which zero and phase were determined using the control. The use of coloring took all that pain away because everything became very clear.

Color marking is almost always applied along the entire length of the conductor. It helps to establish the purpose of each conductor to a specific group in order to facilitate their switching. There are three types of wires in an electrician: phase, zero and ground.

To ensure clarity, simplicity and facilitate the recognition of individual parts of the electrical network in accordance with clause 1.1.30 of the Electrical Installation Code, all electrical installations must have an alphanumeric and color designation. Moreover, the presence of one of these designations does not eliminate the need for the presence of another.

Color marking

The marking of wires by color is the most visual and allows you to quickly determine the purpose of any wire. Such marking can be done by selecting wires with the appropriate color of the core insulation, by applying paint to the busbars, or by painting or using special colored electrical tape at the junctions of the cores.

Moreover, the paint on the tires can not be applied along the entire length, but only at the connection points or at the ends of the tires.

If we talk about the color designation of wires and cables, then we should start with the phase conductors. According to clause 1.1.30 of the PUE in a three-phase network, phase conductors must be marked in yellow, green and red. So, phases A, B and C are respectively designated.
The instruction for a single-phase electrical network assumes the designation of a phase wire in accordance with the color of which it is a continuation. That is, if a phase conductor is connected to phase "B" of a three-phase network, then it should be green.

Note! In a single-phase network of an apartment or house, you often do not know which phase your phase wire is connected to. In order to comply with GOST, you do not have to find out at all. It is enough to designate the phase conductor with any of the proposed colors. Indeed, for a single-phase lighting network, it does not matter at all which phase your conductor is connected to. The only exception is the lighting network, which uses two different phase conductors.

As for the neutral conductors, they should have a blue color. Moreover, the color of the zero core does not depend on whether the three-phase, two-phase and single-phase network is in front of you. It is always marked in blue.
Wire markings with a green/yellow stripe indicate a protective conductor. It is connected to the body of electrical appliances and provides safety against electric shock in case of damage to the insulation of electrical equipment.
If the neutral and protective conductors are combined, then according to clause 1.1.29 of the PUE, such a wire core should have a blue color with yellow-green stripes at its ends. In order to make such a marking with your own hands, you just need to take a blue wire and mark it with paint on its terminations or use colored electrical tape for this.
As for DC networks, the positive core of the wire or bus should be indicated in red, and the negative in blue. In this case, the designation of the zero and protective core corresponds to the marking in AC networks.

Letter marking of wires

But marking wires in color is not always convenient. In the shields, and on the diagrams, the letter designation is much more convenient. It must be used in conjunction with a color code.

The letter marking of phase wires in a three-phase network corresponds to their colloquial designation - phase "A", "B" and "C". For a single-phase network, it should be the same, but this is far from always convenient. Moreover, it is not always possible to reliably determine which phase. Therefore, the designation "L" is often used.

Paragraph 1.1.31 of the PUE normalizes not only the alphanumeric designation of conductors, but also their location. So for a three-phase network with a vertical arrangement of tires, phase "A" should be the highest, and phase "C" the bottom. And with a horizontal arrangement of conductors, the closest phase to you should be phase "C", and the most distant phase "A".

If the wires are marked in the shield, then under the symbol "N" they indicate the neutral wire.
The letter designation "PE" is used to designate the protective conductor. In addition, the ground sign is often used, but the fact is that it cannot always accurately indicate the network diagram.
The fact is that you can meet the designation "PEN". It means the combination of the neutral and protective conductor. This is possible in the TN-C-S systems that we talked about in one of our previous articles.
But the marking of electric DC wires is carried out by the symbolisms “+” and “¬―”. Which respectively means positive and negative wire. For direct current, there is another difference. The zero core is indicated by the symbol "M", which is sometimes misleading.

What do electrical wire colors mean?

Color insulation of conductors today is an essential attribute for successful and correct installation of electrical wiring. Such a solution is by no means a way to make the wires beautiful and attractive to the consumer, it is a convenient color marking, standardized and regulated throughout the civilized world, which is, without exaggeration, a necessity.

Color-coded wires give an accurate identification of each conductor. The color of the core insulation determines its purpose in a group of several conductors and facilitates the process of switching and installation.

This solution eliminates possible errors that could lead to a fatal electric shock or short circuit. Repair and maintenance of electrical networks also becomes safer if the wires are accurately marked.

The standard set out in the PUE strictly defines the colors of the marking, and thanks to this standard, it becomes possible to easily identify each conductor, each cable core in a group by color or by alphanumeric code.

As a rule, the entire conductor has a certain color, but marking only the ends of individual cores is also acceptable, at switching points where it is possible to use colored electrical tape or colored cambric. Next, we will consider in more detail how exactly such marking is performed for single-phase, three-phase current and direct current networks.

Standard color coding for busbars and wires for three-phase AC networks

Phase "A" - colored yellow;
Phase "B" - colored green;
Phase "C" is colored red.

Standard color coding for DC wires and busbars

DC circuits have only two rails: positive and negative. Here, the positive wire (positive charge bus) is marked in red, and the negative wire (negative charge bus) is marked in blue, because the neutral and phase wires are fundamentally absent here. The middle wire (M) is marked in blue.

In the case where a DC network containing two conductors is created by branching off a three-wire DC circuit, the conductors are marked in the same way as the corresponding conductors of the original three-wire circuit.

AC electrical networks are now always laid with a stranded wire in the insulation of cores of different colors, this greatly simplifies the installation process. If one installer performs, and in the future other people will carry out maintenance and repair of the network, they will no longer be forced to constantly identify “phase” and “zero”, they will simply orient themselves by color.

But in the old days, this was a real problem, because the insulation was used in one color - either white or black. Now a standard has been developed, and in accordance with GOST R 50462 “Identification of conductors by colors or digital designations”, the conductors are separate and in cables have strictly regulated designations.

The marking function is to create the ability to quickly and easily visually determine the purpose of each specific conductor for any of its sections, this is one of the main requirements of the PUE. What color, according to GOST, should conductors in AC electrical installations for voltages up to 1000 volts and with a solidly grounded neutral, which include almost all residential buildings and office buildings?

The zero working conductor (N) has a blue marking. For neutral protective conductor (PE) - yellow-green marking in the form of stripes along or across the core. Such a marking in the named combination of colors is relevant only for grounding conductors (for zero protective ones).

When the zero working conductor is made combined with the zero protective (PEN), then the marking is made in blue along the entire length of the wire, and yellow-green stripes are made at the connection points (at the ends of the conductor), or vice versa: a yellow-green conductor with blue ends.

Zero working wire (N) - blue marking;
Zero protective wire (PE) - yellow-green marking;
Zero combined wire (PEN) - yellow-green marking with blue marks on the ends or vice versa.

Phase wires, in accordance with the PUE standard, can be marked with one of these colors: red, black, purple, brown, gray, pink, orange, turquoise, or white. If a single-phase electrical circuit is obtained by branching from a three-phase network, then the phase wire of the resulting single-phase circuit must necessarily match the color of the original wire of the three-phase network from which the branch was made.

The wires are marked so that the colors of the phase wires in no way match the color of the neutral conductor. And if an unmarked cable is used, then color marks are made at the ends of the cores, at the junctions, using heat shrink tubing or colored electrical tape. But to prevent unnecessary work on the manufacture of labels, it is enough to initially choose the right color for the insulation, choosing a cable of sufficient length for your needs.

Sometimes an electrician at work has to deal with not very pleasant situations when the wiring has already been completed, and neither the connections in the shield nor the wires are marked, in this case the person has to spend time and, using a probe, identify “phase”, “zero”, and "grounding".

However, you should always remember that even if it is not possible to purchase a wire of the desired color, you can of course use a wire of any color, but then you must mark the ends of the wires with at least colored heat shrink or colored electrical tape. And always remember that when laying electrical wiring, you must be careful and always follow safety precautions.

Aluminum cable marking

APPV 2x6-380 - aluminum wire, PVC-coated, flat, has a separator (about the definition a little lower), 2 cores with a cross section of 6 mm. It should be noted that the letter designation is used mainly for high-voltage options.

Color coding helps identify the purpose of the cable. It is used for telephone cords, household appliances (fan, video camera), vehicles (VAZ and others), etc. It is this data that is most important when installing cables or.

Blue - working zero;
Green is zero protective;
Black - grounding or "ground";
White is the color marking of wires phase zero.

By the way, different manufacturers may have different types of designations. For example, a phase cable can be white, pink, yellow, orange, gray, red, so be careful when installing or removing cords. When connecting phase or socket, make sure that the colors of the connected cables match.

Labeling of individual electrical cables

Each household device uses a peculiar notation system.

Red - standard USB VDC, Defender Accord km-4810L keyboard connection wire and others.
White is for the USB D connector, while green is for D+.
Black - designed for GND input (available in headphones).

Be careful, the black and red wires are also used to connect the electrical cooler.

Black - ground or connection to the engine ground.
Red is the power cord.
Yellow - power, connects with red.
Blue (if any) - control of the antenna and other functions of the magnetic circuits.

You can buy wires of the desired type (SIP, mounting, flexible and others) in specialized stores, where the marking is also indicated in the certificate and product passport. The price depends on the type of cord.

Wiring inside the house

Wiring inside the house is carried out only with single-phase lines and copper wires. In electrical circuits used for domestic purposes, the working zero must always be blue! According to the PUE, house lines must be laid with a grounding conductor. In all three-core conductors made in accordance with GOST, suitable for interior work, the ground wire is yellow-green.

If the three-core conductor is flexible type PVS, then the phase conductor is usually brown. For in-house wiring, it is better to use wires made of cast copper. If the conductors are marked with stripes, then a conductor with a stripe of any color except blue and yellow-green is phase.

If there is no yellow-green conductor in the cable, use the conductor with a green stripe as the ground wire. The ground wire may be marked in pure yellow. In cables, the cores of which are colored entirely, the white wire is the phase wire.

Connection to the electric stove

A 220 V household electric stove is connected to a special socket that can withstand high power. The color of the cores is red, green, blue, where red is the phase, green is the earth, blue is the neutral conductor.

blue - zero;
yellow-green conductor - grounding;
black conductor - phase A;
brown conductor - phase B.

It is allowed, when connecting to a single phase network, to combine phase conductors on an electric stove under one contact clamp.

Neutral wire

A neutral conductor is a wire connected to the middle (zero) point of an electrical system. In the standard connection scheme, this is a combined zero working and zero protective conductor in a three-phase circuit. The color of the neutral wire is all blue with yellow-green ends or all yellow-green with blue ends.

Wires are marked by color, letters and numbers. Until 2009, GOST interpreted the possibilities of marking wires more widely. Starting in 2009, the standards are being revised towards a clearer classification of colors and the elimination of notes that allow conductors not to be marked.

In the national standard 2009, the terminology has been clarified and the alphanumeric classification has been supplemented. For electrical circuits until 2009, the classic color of conductors was used: yellow, green, red.

Phase A - L1, yellow - brown recommended.
Black is recommended in phase B - L2, green.
Phase C - L3, red - gray recommended.
Zero conductor - N blue.
Combined working zero with a grounding conductor - PEN, blue with yellow-green tips - yellow-green with blue tips.
Grounding conductor - PE, green-yellow.

This combination does not imply any direction of rotation or phasing.

A three-wire or two-wire wire is laid from the junction box to the switch, depending on which type of switch is installed: single-key or. The phase breaks, not the neutral conductor. If a white conductor is available, it will be the power conductor. The main thing is to follow the sequence and consistency in colors with other electricians, so that it doesn’t turn out like in Krylov’s fable: “Swan, cancer and pike”.

On sockets, a protective conductor (yellow-green), most often clamped in the middle of the device. We observe the polarity, the zero worker is on the left, the phase is on the right.

But there are surprises from manufacturers, for example, one conductor is yellow-green, and the other two may turn out to be black.

Perhaps the manufacturer decided, with a shortage of one color, to use what is. Don't stop production! Crashes and bugs are everywhere. If you get exactly the one where the phase is, and where the zero is up to you, you just need to run around with the control.

If the cable is already laid, how to mark

Very often you have to deal with such situations when you come to the object, open the shield, and there the connection is made incomprehensibly how. There is no need to talk about the correspondence of wire marking with the rules. It is not clear what color the phase is laid, and where is zero and ground.

You have to familiarize yourself with the wiring in the shield, junction boxes, etc. It all comes down to one drawback, you have to waste time. How to be in that case? Do not reconnect.

Unfortunately, even today, some electricians use outdated standards during installation work. Because of this, other specialists, during work related to the repair and maintenance of electrical networks, have to look for "phase" and "zero" using a probe.

If it is not possible to buy conductors of the desired color, cables of any color will do. The main thing is that the ends of the wires are correctly marked with heat shrink tubing or colored electrical tape.

In accordance with the rules, it is allowed to carry out color marking not along the entire length, but only at the points of attachment to the buses, that is, at the ends of the cable. To do this, you can designate the wires by color using colored electrical tape or put a heat shrink tube on the ends of the cable.

Of course, there is no need to change the existing marking of conductors, the installation of which was carried out according to the old GOST. But today, when commissioning electrical installations, only new rules should be used.

We remind you that electrical cable laying requires foresight and care from the installer. Be careful!

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