Yellow black wire. Phase and zero wire color: why marking is needed

Recently, the color marking of wires has become very great importance during the electrical work. The use of color codes for phase, zero or ground is very important, as it reduces the likelihood of correct connection wires during repair work, as well as the likelihood of injury due to electric shock.

Colors of electrical wires - how to figure it out?

There is some confusion among electricians now due to the constant change in the color marking of wires. For example, in the late 90s, the earth was designated in black, then this color began to denote zero. Now the reorientation to European designations of wires by color is in full swing. Therefore, we present them:

• Earth - indicated by a yellow-green wire (these colors can also be used separately)
• Zero - indicated in blue
• Zero, aligned with the ground - indicated by yellow-green and blue colors
• Phase - indicated by any other color, but most often white

In a three-phase network, tires and wires are marked in a slightly different way. Tires are indicated by the following colors: Phase A - yellow, phase B - green, phase C - red. Well, traditionally, the zero or neutral wire is indicated in blue, and the ground is yellow-green (in some cases, this bus can be painted black).

What color plus and minus

Another problem is determining the color marking of the plus and minus wires. In our country and in Europe, a black wire is always considered a minus, by default, respectively, white or red or any other shades are a plus. However, in the USA, the marking is completely opposite, where the white wire is a minus. Thus, if you want to determine where the plus is and where the minus is, you should look at the country of the manufacturer, or even better, ring each of the wires.

Additionally, it should be said about the modern letter and color designation of the phase, zero and earth. If you have a single-phase network, then the phase will be denoted by L by the first letter English word line. Zero is marked with the letter N (neutral), and the ground is marked with PE (Protect Erth). In cases where the neutral wire and ground are combined, it is designated PEN.

Note that color coding of wires by color throughout the entire length is not mandatory. To apply a clear marking, it is enough to mark the wire at the junction right color. This can be done using multi-colored shrink tubes, which are simply mounted and last up to 20 years.

Although there are some problems with the accurate identification of wires at this transitional stage, color coding is already useful. In the future, if everyone adheres to the uniform GOST and PUE standards, everything will become even easier. So, now you can install the wires by color, and not engage in constant ringing to determine the phase and zero.

More clearly about the disconnection of cores electrical wires and their marking, see the video:

Electric current is especially dangerous for humans, besides it is not visible. When wiring, use wires different colors for safe and fast work, letters and numbers indicate the cross section of the wire. Color and symbol designations or, in other words, markings are prescribed in the standards, you should not violate it so as not to endanger your own and others' lives.

Color coding core insulation

Visually, the wires differ from each other not only in color and diameter, but also in the number and type of cores. Depending on this characteristic, single-core and multi-core electric wires are distinguished. Their diversity finds its application in chains alternating current both in industrial three-phase networks with a voltage of 380V, and in a home single-phase network of 220V. Power circuits direct current use the same electrical wire standard.

Single-phase two-wire network 220V

Such a network includes an outdated type of wiring, where aluminum wires in a single white braid, popularly "noodles". One vein electric wire- phase conductor, the second core is zero. A single-phase two-wire network is used for ordinary household needs: simple sockets and switches.

How to properly equip the house electrical network,.

The problem with the installation of single-color wiring is the difficulty in determining the phase and neutral wires. The presence of additional measuring equipment will help to cope with the task, you can use a multimeter or a special screwdriver with an indicator, a probe, a tester, a "continuity".

The design of a single-phase two-wire network is allowed by GOST for premises with a small load on the electrical network and low safety requirements. In such cases, two single-core wires or one two-core wire with wires of different colors are used.

In the case of using a solid wire, one core has Brown color, another blue or light blue. According to the generally accepted marking, the brown core is the phase, and the blue one is the neutral conductor, it is strictly not recommended to violate this order. In practice, there are phase wires other than brown: black, gray, red, turquoise, white, pink, orange, but not blue.

The use of two independent solid wires also requires marking. You can use a colored wire along the entire length, for example, blue for zero, red for phase. It is permissible to mark wires of the same color with electrical tape or heat shrink tubes of different colors, placing the marking at both ends of each core.

The use of the tube does not involve wrapping the ends, but putting it on the wire and exposing it to hot air in order to fix the heat shrink on the wire. For home use you can use any colors of marking materials that are accessible and understandable to the wiring installer.

Single-phase three-wire network 220V and the marking used in it

Modern requirements for the installation of electrical wiring dictate the presence of a third wire - grounding. This is the difference and the main advantage of a single-phase three-wire network.

Three electrical conductors perform the corresponding functions: phase, zero and ground, protection against injury by alternating current. The marking of the phase wire remains brown, zero - blue or blue, and the ground wire must be used in a yellow-green braid.

Household appliances that comply with European safety standards require connection to sockets with grounding. Such sockets have a special contact to which a yellow-green wire is connected. It is strictly not recommended to use this color to mark the wire phase and zero in order to avoid possible unpleasant consequences.

Three-phase network 380V

A three-phase network, like a single-phase network, can be with or without grounding. Depending on this, a three-phase four-wire electrical network with a voltage of 380V and a three-phase five-wire network are divided.

A four-wire network consists of three phase conductors and one neutral working conductor; there is no protective earth conductor here. In a five-wire network, in addition to three phase conductors and one zero, there is also a ground conductor.

Similarly with two-phase marking of cores, a blue or blue core is used for the neutral conductor, yellow-green for the ground conductor. Brown is provided for phase A, black is provided for phase B, phase C is marked in gray. There may be exceptions to the rules for phase conductors, their color marking allows the use of other colors, but not blue and yellow-green, which already have their own function.

Single-phase load grouping or three-phase load connection uses four-core and five-core wires.

DC network

A DC network differs from an AC network in that it contains two conductors: plus and minus. The positive conductor conductor is marked in red, and the negative conductor conductor is marked in blue.

The practice of color separation of wires is familiar to professionals and amateurs in their field, is actively used in electrics, but still you should not blindly trust the markings. Safety net measuring instrument– thoughtful and balanced course during installation electrical networks, they should not be neglected.

If you are an electrician, your opinion about the article is useful to us. Please write your comment below.

Switching wiring in a private house must be carried out by color. The best answer on how wires are marked by color is given by GOST R 50462. But unfortunately, practice shows that electrical lines in the private sector, it is not uncommon that they perform not with the material they should, but with what they have. This article does not cover other technical aspects wiring devices. The following information gives an idea of ​​how the conductors should be color-coded correctly and how to remedy the situation in the event of a discrepancy.

The conductors may be colored in their entirety or marked with a thin strip of color along the length of the conductor's insulation. We also produce cable products that have a two-color color.

The color of the phase and neutral wires in the input cable

The supply lines leading to the house can be made in several versions. It all depends on the type of cable. If single-phase input is performed:

1. With a SIP type wire, the phase conductor will have a colored stripe (usually yellow, green or red). Zero core black.
2. Cable type AVVG or VVG, then the neutral conductor is blue, white, red or green - phase.
3. Cable type KG - phase wire brown, zero - blue.

If a three-phase input is performed:

1. A SIP-type wire and in addition to the two primary colors of red and green, blue and black wires - the neutral wire will necessarily be black.
2. With an AVVG or VVG type cable, the neutral conductor will be blue, and one of the phase conductors, in addition to red and green, will be black or white.
3. Cable type KG zero - blue, brown and two black - phase conductors.

Cable products are often produced not according to GOST, but according to specifications. Therefore, even in a two-core SIP with black and blue, the black wire will be zero. The black wire contains a steel core, which performs the self-supporting function of the wire. Connecting the input to the house from overhead lines with a VVG and KG type cable is not recommended.

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 internal works, ground wire - yellow green.

If the three-core conductor is flexible type PVS, then the phase conductor is usually brown. For inside 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 can be marked cleanly yellow. In cables, the cores of which are colored entirely, the white wire is the phase wire.

Connection to the electric stove

A 220v household electric stove is connected to a special outlet 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. There is a nuance in electric stoves and hobs, foreign-made, designed for 220/380V, the connection is made with a four-wire 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

Neutral conductor is a wire connected to the middle (zero) point electrical system. IN standard scheme connection 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.

Designation of wires phase, zero, earth

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

In the classic version of three-phase circuits up to 1000 volts, conductors are marked in the following combinations:

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

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

What color is the phase and zero

In single-phase lines without a ground conductor, the phase conductor is marked in red, the zero conductor is marked in blue. Also often there is a combination of phase - white color, neutral wire - blue. The worst combination of wire colors, phase, zero, earth found in the coloring of conductors is white, red, black.

If we take identification standards, the phase wire should be red, black - ground conductor, white - zero. But from practice it is better to make zero red, and the phase white. Visually, zero conductors will be better visible. There is a danger of mixing phase and neutral conductors made different materials! It is better to mark the ends of the conductors with insulating tape in standard colors.

Color-coded wire marking for DC lines

DC circuit conductors are recommended to be painted as follows:

• positive pole - red (recommend brown insulation);
• minus pole - blue (grey is recommended);
• ground conductor in a three-wire DC circuit - blue (recommended since 2009 of blue color).

The polarity of the wires by color can be determined more easily. Cold colors - negative terminal, warm colors- plus. If there are taps in a three-wire DC electrical circuit, then the outgoing lines must be the same color as the supply lines. What color the plus and minus wires were not painted, it is necessary to mark them with an alphanumeric marker.

Electrical wire colors

Even GOST is not mandatory. Conductors can be colored black, blue, green, yellow, brown, red, orange, purple, grey, white, pink, turquoise colors. Prohibitions on the use of yellow and green are clearly given.

The cable cannot contain a core marked with a double color, in combination with yellow or green with anything else, except for just one yellow-green conductor.

To avoid confusion, it is better to put heat shrink tubing on the ends of the conductor. classic colors. Enough 10 cm tube desired color. The opinion in this article is subjective and contains only a recommendation, based on the assumption that all other rules for the installation of electrical installations will be observed.

Video about marking wires and cable lines

For the correct connection of wires, their color marking is used, which allows you to quickly find the desired conductor in the bundle. But not everyone knows as indicated by the phase and zero in the electrician, therefore, colors are often confused, which makes future wiring repairs difficult. In this article, we will analyze the principles of color marking wires and tell you how to properly breed phase, ground and zero.

Wires must be connected to each other only in strict accordance. If mixed up, a short circuit will occur, which can lead to equipment failure or the cable itself, and in some cases even a fire.

Standard wire colors

Marking allows you to connect wires correctly, quickly find the right contacts and work safely with cables of any type and shape. Marking, according to the PUE, is standard, therefore, knowing the principles of connection, you can work in any country in the world.

Note that the old cables produced under the USSR had one conductor color (usually black, blue or white). To find the desired contact, they had to ring or apply a phase to each wire in turn, which led to unreasonable waste of time and common mistakes(many remember the freshly built Khrushchevs, in which, when you press the bell, front door the light in the bathroom turned on, and when the switch in the bedroom was pressed, the power was lost in the outlet in the hallway).

Various greatly simplified the process of creating wiring, and after a few years became the standardin Russia, EU, USA and other countries of the world.

Earth, zero and phase

In total there are three types of wires: ground, zero and phase. The coloring is applied to the entire wire, so even if you cut the cable in the middle, you can still understand where the contact is.Grounding is indicated as follows:

1. Yellow-green color (in the vast majority of cases).
2. Green or yellow.

In the wiring diagram, grounding is abbreviated as PE.

Note:in blueprints and electrician slang, grounding is often referred to as null protection. Do not confuse it with zero, otherwise a short circuit will occur.

Zero in the cable is indicated in blue-white or just blue, the designation in the diagram is the letter N. Sometimes it is called neutral or zero contact, so be careful not to confuse these concepts.

Now let's figure outis used most often. Here you will have a hard time, because there can be a lot of options. We advise you to go the opposite way - first find the yellow-green ground, then the blue zero, and the wires remaining in the cable will be the phase. It is necessary to connect them according to the colors so that there is no confusion. Most often in three-core systems they are marked brown, but there may be other options:

• the black;
• Red;
• Gray;
• White;
• pink.

On the schematic images, the phase is displayed with the letter L. You can detect it with a test screwdriver or a multimeter. When connecting wires, use special clamps or solder them offset from each other so that a short circuit or oxidation of contacts does not occur, followed by a loss of voltage.

The classic color of the wires in the cable

The difference between zero and ground

Some novice electricians do not knowand why is it even needed. Let's analyze this issue in more detail. Flows through zero and phase electricity so you can't touch them. The ground also serves to drain the voltage if it breaks through the body of the device. This is a kind of protection, which in last years became mandatory - some devices do not work if they are not grounded.

Attention:do not ignore the grounding requirement - accumulated static electricity or breakdown can damage the device or give you an electric shock.

If you are not sure which of the wires is ground and which is zero, then use the following tips. They will help you decide wire colors:

1. Measure the resistance of the wire - it will be less than 4 ohms (check that there is no voltage on it so as not to burn the multimeter).
2. Find the phase, use a voltmeter to measure the voltage between the expected zero and ground. On ground, the value will be higher than at zero.
3. If you measure the voltage between ground and a grounded device (for example, a battery in high-rise building), then the voltmeter will not detect voltage. If you measure the voltage between zero and ground, then a certain value will be displayed.

All this is true only for three- or more conductor cables. If there are only two wires in the cable, then by default one of them will be ground (blue), the second phase (black or brown).

Observe cable connection rules

Looking for a phase

You already know what color of wires phase, zero, ground. Consider the main question - how to find the phase. If you are going to connect an outlet, then you, in fact, do not care about this issue - there is no difference on which contact to apply phase or zero. But the switch is different.

Attention:in the switch, the phase always opens, and zero comes to the light bulb. This is necessary so that during the repair or replacement of the lamp you are not shocked. The phase must be started up on the lower contact of the cartridge, zero - on the side.

If there are two single-color wires in the wiring, then the easiest way is to find the phase with an indicator - when you touch a bare wire, it starts to glow. Before touching the wire, turn off the power, strip the insulation on the wire (1 cm is enough), spread the wires in different directions so that there is no short circuit. Then turn on the power and touch the indicator to the contact. Thumb hands should be placed on upper part screwdrivers, where the contact pad is located. After that, the LED on the indicator should light up. This will allow you to find the phase, but the device will not help you figure out between zero and ground. To find out what color is the ground wire in a three-wire wire, you will need to use the above methods.

You can find the phase with an indicator

Conclusion

If you are creating a new wiring, then be sure to comply with the PUE electrical wire marking - this will help you in the subsequent repair of the system, because you can easily identify the wires by color. Use green/yellow for ground, blue for neutral, brown/black/white for live. In cables with big amount phases, connect the contacts only by color, using the appropriate clamps and heat shrink. If you have to work with old wiring, where the colors do not meet the standard, then first of all look for the phase using indicator screwdriver. The contact that does not glow will be the desired zero.

When laying wires, follow the rules - they should only run horizontally and vertically. No need to try to save money by dragging them down an incline across the entire wall or ceiling - in the future you simply won't be able to find them or hook/kill them during repairs, which will lead to serious consequences. Once and for all remember colors of wires in a three-core cable - this will help you in life, because any electrician is faced with repairing sockets, switches, electrical panels, laying new lines, etc.

Today it is difficult to imagine electrical wiring without the use of colored insulation. And these are not marketing "chips" of manufacturers seeking to present their goods in paints, and unfashionable innovations that consumers strive for. In fact, this is a simple and practical necessity, which is determined by strict state standards for compliance with the correct marking. What is it for.

Wire colors in electrical connections

Color marking

All variety of colors and certain colors selected from this palette - reduced to one (single) standard (PUE). Thus, wire strands are identified by color or by letter and number designations. The adoption of a single standard for the color identification of electrical wires greatly facilitated the work associated with their switching. Each core has a specific purpose and is indicated by the corresponding tone (blue, yellow, green, gray, etc.).

Color marking of wires is done along their entire length. Additionally, identification is carried out at the connection points and at the ends of the cores. To do this, use colored electrical tape or heat-shrink tubes (cambric) of the corresponding tones.

Let's take a look at how wiring is done and the color marking of wires for three-phase, single-phase and DC networks.

Color marking of wires and buses of alternating three-phase current

The coloring of tires and high-voltage bushings of transformers in three-phase networks is done as follows:

• tires with phase "A" are painted with a yellow palette;
• tires with phase "B" - green tone;
• tires with phase "C" - in red.

Color marking of wires. Wire colors in electrical (DC busbars)

IN national economy often use DC circuits. They find their application in certain areas:

In DC networks there is no phase and zero contact. For such networks, only two contacts of different polarities are used - plus and minus. To distinguish them, respectively, two colors are used. A positive charge turns red and a negative charge turns blue. Blue color indicates the middle contact, which is marked with the letter "M".

The "old-timers" of wiring are probably familiar with the old methods of wiring and color coding of electrical wires. Primary colors electric cable were white and black. But that time is long gone. Each color now, and there are clearly not two of them, has its own purpose and dominant profile.

Contact colors in electrics indicate the purpose and belonging of the conductors to a certain group, which facilitates their switching. The possibility of an error during the installation process, which can lead to a short circuit during a test connection or an electric shock during a repair, is greatly reduced.

Color marking of wires. The color palette of the protective zero and working contact

Zero working contact is indicated blue tone and the letter N. The PE marking denotes a zero protective contact, which is painted in yellow-green stripes. The combination of such tones is used when marking pinching conductors.

A blue conductor along its entire length with yellow-green stripes at the junctions indicates a combined zero working and zero protective connection (PEN). However, GOST also allows the reciprocal opposite of this color:

1. Working zero contact denoted by the letter N and has a blue color.
2. Protective null(PE) with yellow-green color.
3. Combined(PEN) is identified by a yellow-green color and a blue mark at the ends.

Single-phase electrical circuit. Coloring of phase wires

According to PUE standards, phase contacts are usually indicated in black, red, purple, white, orange or turquoise.

Single-phase electrical circuits are created by branching a three-phase electrical network. In this case, the color of the phase contact single-phase circuit must match the color of the phase wire of the three-phase connection. In this case, the color marking of the phase contacts should not match the N - PE - PEN coloring. On unmarked cables, colored marks are placed at the junction. To designate them, use colored electrical tape or heat shrink tube(cambric).

What color is the ground wire. Wire marking by color (phase - zero - earth)

When installing lighting networks and power supply to sockets, a cable with three wires (three-core cable) is used. Using the standard color system(color of phase-zero-ground wires) significantly reduces repair time. Stranded wiring in standard multi-colored insulation greatly simplifies the laying of electrical circuits and installation work for wiring AC networks with its grounding. This is especially true when wiring and repairing an electrical system, which is done by different masters, but under the general guidance of GOST. Otherwise, each master would have to once again double-check the work of his predecessor.

"Earth" is usually indicated in yellow-green and marked PE. Sometimes there is a green-yellow color and marking "P E N". In this case, there is a blue braid at the ends of the electrical wire at the attachment points and grounding is combined with neutral.

The switchboard is connected to the ground bus and to the metal door of the switchboard. Junction box usually connected to grounded wires of lamps or grounding contacts of sockets.

Color marking of wires. Designation of zero and neutral

"Zero" is indicated in blue. IN switchboard it is connected to the zero bus and is indicated by the letter N. All blue wires are also connected to the bus. It is connected to the output using a meter or directly, without installing an automatic device.

The wires of the distribution box (with the exception of the wire from the switch) are indicated by a blue neutral palette. When connected, they do not take part in the switching process. "Neutral" blue wires are connected to sockets and contact N, which is indicated on the reverse side of the socket.

Color marking of wires. Phase color code

The phase wire is usually marked in red or black. Although its coloring may not be so unambiguous. It can also be brown, but never blue, green or yellow. In automatic shields, the "phase" coming from the load of the consumer is joined to the lower contact of the meter. The switching of the phase wire is carried out in switches. In this case, the contact is closed during shutdown and voltage is supplied to the consumers. The black wire of the phase socket is connected to the contact, which is denoted by the letter L.

Alphanumeric designation of wires by color

Knowing the elementary color markings of wires and their purpose will help any amateur electrician in installing home wiring (with grounding). If you wish, you can easily make it according to the required standards in compliance with all technical standards.