There are, in fact, not many different types of conductors and their connections. In the electrical power industry, a distinction is made between supply and protective conductors. Some have heard words such as “neutral” and “phase” wire. However, this is where questions arise. How to determine zero and phase in a real network?

What kind of conductors are there in a socket?

You can understand the question “what is phase and zero” without delving into the jungle of clarifying the structure, advantages and negative aspects of three-phase or five-phase circuits. You can practically disassemble everything on your fingers by opening the most ordinary household outlet, which is installed in an apartment or private house ten to fifteen years ago. As you can see, this outlet connects to two wires. How to determine zero and phase?

How do the wires in a socket work and why are they needed?

As you can see, there are certain differences between workers and zeros. What is the symbol for phase and zero? A bluish or blue color is the color of the phase wire, while zero is indicated by any other colors, with the exception, of course, of blue colors. It can be yellow, green, black and striped. There is no current flowing. If you take it and do not touch the worker, then nothing will happen - there is no potential difference on it (in essence, the network is not ideal, and there may still be a small voltage, but it will be measured in millivolts at best). But this will not work with a phase conductor. Touching it may result in an electric shock, even fatal. This wire is always energized; current flows to it from generators and transformers and stations. You must always remember that you should never touch the working conductor, since voltage of even a hundred volts can be fatal. And in the outlet it is two hundred and twenty.

How to determine zero and phase in this case? The socket, designed in accordance with European standards, contains three conductors at once. The first is phase, which is energized and painted in a variety of colors (with the exception of blue shades). The second is zero, which is absolutely safe to touch and is colored. But the third wire is called neutral protective. It is usually colored yellow or green. It is located in the sockets on the left, in the switches - at the bottom. The phase wire is located on the right and top, respectively. Taking into account such colors and features, it is easy to determine where the phase is, and where is the zero, and where is the protective neutral wire. But what is it for?

Why is a protective conductor needed in European sockets?

If the phase wire is intended to supply current to the socket, and the neutral wire is intended to lead to the source, then why do European standards regulate another wire? If the equipment that is connected is working properly, and all wiring is in working condition, then the protective zero will not take part, it is inactive. But if suddenly an overvoltage occurs somewhere, or a short circuit occurs on some parts of the devices, then the current enters places that are usually without its influence, that is, not connected to either a phase or a zero. A person will simply be able to feel the electric shock on himself. In the worst situation, you can even die from this, since the heart muscle can stop. This is where the protective neutral wire is needed. It "takes" the short circuit current and directs it to the ground or to the source. Such subtleties depend on the wiring design and the characteristics of the room. Therefore, you can safely touch the equipment - there will be no electric shock. The thing is that current always flows along the path of least resistance. In the human body, the value of this parameter is more than one kiloOhm. The resistance of the protective conductor does not exceed a few tenths of one Ohm.

Determining the purpose of conductors

How to determine zero and phase? Any person has encountered these concepts in one way or another. Especially when you need to fix an outlet or do some wiring. Therefore, it is necessary to understand exactly where each conductor is. But how to determine zero and phase? It must be remembered that all manipulations of this kind with electricity are dangerous. Therefore, if you are unsure of your actions, it is better to contact a specialist. If you are already approaching the outlet and the wires in it, then you must first completely turn off the power to the entire apartment. At a minimum, this can save health and life. As mentioned earlier, usually the designation of phase and zero is done using coloring. With proper labeling, distinguishing them will not be difficult. Black (or brown) is the color of the phase wire; neutral usually has a bluish or bluish tint. If a European standard socket is installed, then the third (protective zero) is green or yellow. What to do if the wiring is one color? As a rule, in this case, at the ends of the wires there are usually special insulating tubes that have the necessary color markings. They are called "cambrics".

Identifying conductors using a special screwdriver

How to determine zero and phase? To do this, it is most convenient to buy a special indicator screwdriver. The handle of such a device is made of translucent or transparent plastic. There is a built-in diode - a luminous light bulb - inside. Upper part This screwdriver has a metal one. How to determine zero and phase using this method?

The procedure for performing measurements using an indicator screwdriver:

• de-energize the apartment;
• lightly strip the ends of the wires;
• we move them apart so as not to accidentally cause a short circuit by contacting the phase and zero;
• turn on the switch and supply current to the apartment;
• We take the screwdriver by the handle, which has a dielectric coating;
• place your finger (thumb or forefinger) on the contact, which is located on the back of the socket;
• touch the working end of the indicator to one exposed conductor;
• carefully observe the reaction of the screwdriver;
• if the diode lights up, then we can confidently state that;
• By method of elimination we understand that the remaining conductor is zero.

The indicator screwdriver reacts to the presence of voltage. Naturally, it is not in the neutral wire. However, there is significant drawback such a method. By using indicator screwdriver It is impossible to understand how to determine: phase, zero, ground - where is what in the case of a European socket.

Method for determining phase and zero using a voltmeter

If the wires are not painted in the appropriate colors, and you don’t have an indicator screwdriver at hand, then you can go another way. We need a voltmeter (multimeter, tester). It is necessary to set it to the required range - over two hundred volts AC. How to determine the phase with a tester? We take one conductor that extends from the device (labeled V). We attach it to a previously de-energized conductor (any). Then we apply current (turn on the switch). And we simply record what the device display shows. After all of the above, turn off the power again and transfer the tester clamp to another conductor. If there is nothing on the display, this means that in front of us there is either a zero or a grounding protective neutral wire. However, you can use another method that answers the question: “How to determine zero and phase, as well as grounding.” To do this, we turn off the power to the apartment again and fix the V clamp on one of the wires. We also throw the second one onto any of the three conductors. The voltage turns on. If the arrow does not move, then you have chosen zero and protective. Accordingly, the voltage must be turned off again and the position of terminal V must be changed (place it on another previously unused conductor). We turn on the current again and take the appropriate measurements. Then we perform the same operation, but change the conductor again. Now you need to compare the results. If the first digit turned out to be larger, it means that we measured the voltage between the phase conductor (on which terminal V hung) and the neutral one. Accordingly, the second wire will be a protective grounding wire. This method is based on measuring the potential difference.

Exotic ways to determine phase and zero in wiring

There are also " traditional methods", which do not imply the presence of any special devices. They can be used only in the most extreme cases, since they are associated with an increased danger to health and life. For example, the potato method. To do this, put a freshly cut piece of potato on the previously de-energized conductors. It is necessary to prevent the wires from touching each other so that there is no short circuit between them. Then literally apply voltage for a couple of seconds and look at the potatoes. If one section near the wire turns blue, then a phase is connected to it.

Electrical cables produced during the USSR period had predominantly black or white insulation, which created difficulties and inconveniences during electrical work, because It was not always possible to quickly identify the purpose of a particular wire. Nowadays there are cables of various colors on the shelves. This variety has quite specific goal. Color marking of wires of each type (zero, minus, plus, ground and various phases) is primarily intended to make electrical work safer, and finding and connecting contacts easier and faster.

To avoid any discrepancies in color scheme, depending on which manufacturer manufactured this product, it is strictly standardized in the PUE (electrical installation rules) and state standards. Until 2009, GOST R 50462-92 was used; in GOST R 50462-2009, which replaced it, changes were made regarding the colors of wires in three-phase networks, the color of plus, minus and zero in DC networks; brown was recommended as the main shade for the phase in a single-phase network, the use of a combination of yellow and green for grounding is approved.
There are different types of cables:

• Black
• Brown
• Red
• Orange
• Yellow
• Green
• Blue
• Purple
• Gray
• White
• Pink
• Turquoise

The cable is marked in the right color at the ends (in other words, in the area of ​​connections), as well as along the entire length in the form of continuous colored insulation or individual marks.

Coloring of different types of cables

Three-phase networks

In a three-phase network of transformer substations with alternating current, according to GOST 1992, phase A has a yellow wire, B has a green wire, C has a red wire. According to the new GOST, it is preferable to use brown for phase A, black for phase B and gray for phase C. In conventional household cables for phase A, white is used, for phase B - black, for phase C, also red.
The ground wire is usually colored in the form of yellow-green stripes in the longitudinal or transverse direction. Moreover, each color cannot occupy less than 30% and more than 70% of the surface. Less commonly, the ground cable marking may be only yellow or only green. If such a cable is laid open method, then it is permissible to use black color as it improves corrosion protection. Also, the color black was used to indicate the ground wire everywhere before changes were made to regulatory documentation in 2009.
Zero has blue or light blue wire insulation.

Single-phase networks

In this type of AC network, the phase insulation is most often brown, gray or black, but red, purple, pink, white and turquoise are also acceptable. At the same time, in a single-phase network powered by a single-phase energy source, wires with brown insulation are usually used. If a single-phase conductor is made as a branch of a three-phase electrical circuit, then it is marked with the same color as the phase of the three-phase circuit.
The ground wires, similar to the previous case, are marked with a combination of yellow and green.
PEN conductors, in which the protective zero and working zero are connected along the entire length, are painted blue and have yellow-green markings at the ends. At the same time, GOST allows another option - yellow-green lines along the entire length of the wire and blue marks at the ends.

DC networks

If a system with a DC network was put into operation before 2009, then the zero should be light blue, the plus should be red, and the negative pole should be dark blue. According to the new GOST, brown should be used for plus, gray for minus, and blue for zero.

Labeling rules

Marking is performed on the ends of the wires, i.e. in places where they are connected to each other or to various equipment.
It is permissible to combine colors permitted for marking, but avoid confusion whenever possible. So, yellow and green can only be used in combination with each other and only for grounding, and not, for example, plus/minus.
If the wires in the system are initially marked incorrectly or not marked at all, this can be corrected:

• By applying letter, symbol or color markings with indelible markers (convenient if the wire is white or at least light)
• Sticker of polyurethane tags with inscriptions
• Using heat shrink tubing or insulating tape of the desired color

Naturally, you need to first determine which wire is positive, which is negative, etc. the purpose of each wire (in a household electrical network this can be done using an indicator screwdriver or a multimeter).
It is not always possible to create a color circuit diagram in paper version. Then, in black and white copies, letter designations are used to uniquely identify the color of each type of wire. Their full list given in GOST R 50462-2009. For marking cables containing multiple wires different types V letter designations different colors are separated by a plus sign.

Conclusion

Color marking of wires depending on the purpose of each of them allows you to make electrical installation work more convenient, reduces the likelihood of errors and emergency situations. Therefore, it is necessary to comply with it even for the individual power supply system of an apartment or house, not to mention larger industrial, commercial, public and other facilities.

Today it is difficult to imagine electrical wiring without the use of colored insulation. And these are not marketing “tricks” of manufacturers seeking to present their goods in colors, 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 correct labeling. What is this for?

Wire colors in electrical connections

Color marking

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

Wires are marked by color along their entire length. Additionally, identification is carried out at connection points and at the ends of the cores. To do this, use colored electrical tape or heat-shrinkable tubes (cambrics) of appropriate colors.

Let's look at how electrical wiring is done and color coding wires for three-phase, single-phase and DC networks.

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

Painting of busbars and high-voltage transformer bushings in three-phase networks is done as follows:

• tires with phase “A” are painted yellow;
• buses with phase “B” - green;
• buses with phase “C” - red.

Marking of wires by color. Electrical wire colors (DC buses)

In the national economy, direct current circuits are often used. They find their application in certain areas:

In DC networks there is no phase and neutral contact. For such networks, only two contacts of different polarities are used - plus and minus. To distinguish them, two colors are respectively 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”.

“Old-timers” of electrical installation are probably familiar with the old methods of wiring and color marking of electrical wires. The main colors of the electric cable were white and black. But that time is a thing of the past. Each color now, and there are clearly more than two, has its own purpose and dominant profile.

Contact colors in electrics indicate the purpose and belonging of conductors to a specific group, which facilitates their switching. The likelihood of an error during the installation process, which could lead to a short circuit during a test connection or electric shock during repairs, is significantly reduced.

Marking of wires by color. Color palette of protective zero and working contacts

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

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

1. Working zero contact is designated by the letter N and is blue in color.
2. Protective zero(PE) with a yellow-green color.
3. Combined(PEN) are identified by their yellow-green color and blue markings 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 off a three-phase electrical network. In this case, the color of the phase contact of a single-phase circuit must match the color of the phase wire of a three-phase connection. In this case, the color marking of the phase contacts should not match the N - PE - PEN colors. On unmarked cables, colored marks are placed at the connection point. To mark them use colored electrical tape or heat shrink tube(cambric).

What color is the ground wire? Marking of wires by color (phase - zero - ground)

When installing lighting networks and power supply to sockets, use a cable with three wires (three-core cable). The use of a standard color system (phase-neutral-ground wire color) significantly reduces repair time. Multi-core wiring in standard multi-colored insulation greatly simplifies the laying of electrical circuits and installation work on wiring AC networks with its grounding. This is especially true when wiring and repairing the 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 by the color yellow-green and marked PE. Sometimes there is a green-yellow color and the marking “P E N”. In this case, there is a blue braid at the ends of the electrical wire at the attachment points and the grounding is combined with the neutral.

The distribution panel is connected to the grounding bus and to the metal door of the panel. The junction box is usually connected to the grounded wires of fixtures or the grounding pins of outlets.

Marking of wires by color. Designation of zero and neutral

“Zero” is indicated in blue. IN switchboard it is connected to the zero bus and is designated 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 distribution box wires (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. The blue “zero” wires are connected to sockets and contact N, which is indicated on back side sockets

Marking of wires by color. Phase color designation

The phase wire is usually indicated in red or black. Although its colors may not be so clear. It can also be brown, but never blue, green or yellow. IN automatic shields The “phase” coming from the consumer load is connected to the lower contact of the meter. Switching of the phase wire is carried out in switches. In this case, the contact closes during shutdown and voltage is supplied to consumers. The black wire of the phase socket is connected to the contact, which is designated by the letter L.

Alphanumeric designation of wires by color

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

Those who have dealt with electrical wires at least once in their lives could not help but notice that the cables always have different insulation colors. It was not invented for beauty and bright colors. It is thanks to the color scheme in clothing that wires are easier to recognize phases, grounding and neutral wires. All of them have their own coloring, which many times makes it convenient and safe work with electrical wiring. The most important thing for the master is to know which wire should be marked with which color.

Wire color coding

When working with electrical wiring, the greatest danger is represented by the wires to which the phase is connected. Contact with the phase can be fatal, so the brightest warning colors, for example red, were selected for these electrical wires.

In addition, if the wires are marked with different colors, then when repairing a particular part, you can quickly determine which of the wire bundles need to be checked first, and which of them are the most dangerous.

Most often, the following colors are used for phase wires:

• Red;
• Black;
• Brown;
• Orange;
• Lilac,
• Pink;
• Violet;
• White;
• Gray.

It is these colors that phase wires can be painted. You can deal with them easier if you exclude the neutral wire and ground. For convenience, in the diagram the image of a phase wire is usually denoted by the Latin letter L. If there is not one phase, but several, a numerical designation should be added to the letter, which looks like this: L1, L2 and L3, for three-phase in 380 V networks. In some designs, the first phase (mass) may be designated by the letter A, the second by B, and the third by C.

What color is the ground wire?

According to modern standards, the grounding conductor should be yellow-green in color. In appearance it looks like yellow insulation, on which there are two longitudinal bright green stripes. But sometimes there is also a color of transverse green-yellow stripes.

Sometimes, the cable may only have bright green or yellow conductors. IN in this case“earth” will be indicated by this color. It will also be displayed in the corresponding colors on the diagrams. Most often, engineers draw bright green wires, but sometimes you can see yellow conductors. On diagrams or devices, “ground” is designated by the Latin (in English) letters PE. Accordingly, the contacts where the “ground” wire needs to be connected are also marked.

Sometimes experts call the grounding wire “neutral and protective,” but this should not be confused. If you see such a designation, then know that this is an earth wire, and it is called protective because it reduces the risk of electric shock.

The zero or neutral wire is marked in the following color:

• Blue;
• Blue;
• Blue with white stripe.

No colors are used in electrical engineering to mark the neutral wire. This is how you will find it in any, be it three-wire, five-wire, or maybe with even more conductors. Blue and its shades are usually used to draw “zero” on various schemes. Professionals call it a working zero because (which cannot be said about grounding) it is involved in electrical wiring with power. Some, when reading the diagram, call it a minus, while everyone considers the phase “plus”.

How to check wire connections by color

Electrical wire colors are designed to make it easier to identify wires. However, relying only on the color is dangerous, because some newbie, or an irresponsible employee from the housing and communal services complex, could connect them incorrectly. In this regard, before starting work, it is necessary to ensure that they are correctly marked or connected.

In order to check the wires for polarity, take an indicator screwdriver or a multimeter. It is worth noting that it is much easier to work with a screwdriver: when you touch the phase, the LED built into the housing lights up.

If the cable is two-wire, then there are practically no problems - you have eliminated the phase, which means the second conductor that remains is zero. However, three-core wires are also common. Here you will need a tester or multimeter to determine. With their help, it is also not difficult to determine which wires are phase (positive) and which are neutral.

This is done as follows:

• The switch is set on the device in such a way as to select a jackal of more than 220 V.
• Then you need to take two probes in your hands, and holding them by the plastic handles, very carefully touch the rod of one of the probes to the found phase wire, and lean the second one against the supposed zero.
• After this, the screen should display 220 V, or the voltage that actually exists in the network. Today it may be lower.

If the display shows a value of 220 V or something in this range, then the other wire is zero, and the remaining one is presumably “ground”. If the value that appears on the display is less, you should continue checking. We again touch the phase with one probe, and the supposed ground with the other. If the instrument readings are lower than in the case of the first measurement, then in front of you is “ground”. According to standards, it should be green or yellow. If suddenly the readings turn out to be higher, this means that you have made a mistake somewhere, and you have a “zero” wire in front of you. The way out of this situation is to either look for exactly where the wires were connected incorrectly, or leave everything as is, remembering that the wires are mixed up.

Wire designations in electrical diagrams: connection features

When starting any electrical installation work on lines where a network has already been laid, you need to make sure that the wires are connected correctly. This is done using special testing devices.

It must be remembered that when checking the phase-zero connection, the readings of the indicator multimeter will always be higher than in the case of continuity of the phase-ground pair.

According to the standards, wires in electrical circuits are color coded. This fact allows the electrician to find zero, grounding and phase in a short period of time. If these wires are connected incorrectly to each other, a short circuit will occur. Sometimes such an oversight results in a person receiving an electric shock. Therefore, you cannot neglect the rules (PUE) of connection, and you need to know that the special color marking of wires is intended to ensure safety when working with electrical wiring. In addition, this systematization significantly reduces the electrician’s work time, since he is able to quickly find the contacts he needs.

Features of working with electrical wires of different colors:

• If you need to install a new one or replace an old outlet, then it is not necessary to determine the phase. The plug doesn’t care at all which side you connect it to.
• In the case when you connect a switch from a chandelier, you need to know that it needs to be supplied with a specific phase, and only zero to the light bulbs.
• If the color of the contacts and phase and zero are exactly the same, then the value of the conductors is determined using an indicator screwdriver, where the handle is made of transparent plastic with a diode inside.
• Before identifying a conductor, the electrical circuit in a house or other room must be de-energized, and the wires at the ends must be cleaned and spread apart. If this is not done, they may accidentally come into contact and result in a short circuit.

The use of color marking in electrical engineering has made people's lives much easier. In addition, thanks to color coding, safety when working with live wires has risen to a high level.

Designations and colors of wires in electrical engineering (video)

Those who work with electrical wiring, whether they are skilled craftsmen or novice electricians, should be careful during the installation of electrical wiring and know which wire is designated as. When laying wiring and connecting contacts, always connect the conductors according to the color markings according to the new rules, and for the sake of your safety and respect for those who will work with them in the future, do not confuse them. Remember that your mistake can lead to negative and disastrous consequences.

In most modern cables, the conductors have insulation of different colors. These colors have a certain meaning and are chosen for a reason. What is color marking of wires and how to use it to determine where the zero and ground are, and where the phase is, and we will talk further.

In electrical engineering, it is customary to distinguish wires by color. This makes the work much easier and faster: you see a set of wires of different colors and, based on the color, you can guess which one is intended for what. But, if the wiring is not factory-made and you did not do it, before starting work you should definitely check whether the colors correspond to the intended purpose.

To do this, take a multimeter or tester, check the presence of voltage on each conductor, its magnitude and polarity (this is when checking the power supply network) or simply call where and where the wires come from and whether the color changes “along the way.” So knowing the color coding of wires is one of the essential skills of a home craftsman.

Ground wire color coding

According to the latest rules, wiring in a house or apartment must be grounded. Recent years all household and construction equipment Available with a grounding wire. Moreover, the factory warranty is maintained only if the power supply is supplied with a working grounding.

To avoid confusion, it is customary to use a yellow-green color for the ground wire. The hard solid wire has a green base color with a yellow stripe, while the soft stranded wire has a yellow base color with a green longitudinal stripe. Occasionally there may be specimens with horizontal stripes or just green, but this is not standard.

Ground wire color - single-core and stranded

Sometimes the cable only has bright green or yellow wire. In this case, they are used as “earthen”. On diagrams, “ground” is usually drawn green. On the equipment, the corresponding contacts are signed in Latin letters PE or in the Russian version they write “earth”. A graphic image is often added to the inscriptions (in the figure below).

In some cases, in the diagrams, the ground bus and the connection to it are indicated in green

Neutral color

Another conductor that is highlighted in a certain color is neutral or “zero”. The color blue is allocated for it (bright blue or dark blue, occasionally blue). On color diagrams, this circuit is also drawn in blue and signed with the Latin letter N. The contacts to which the neutral must be connected are also labeled.

Neutral color - blue or light blue

In cables with flexible stranded wires, as a rule, lighter shades are used, and solid solid conductors have a sheath of darker, richer tones.

Coloring phase

With phase conductors it is somewhat more complicated. They are painted in different colors. Already used ones are excluded - green, yellow and blue - and all others can be present. When working with these wires, you need to be especially careful and attentive, because they are the ones where voltage is present.

Color marking of wires: what color is the phase - possible options

So, the most common color markings for phase wires are red, white and black. There may also be brown, turquoise orange, pink, purple, gray.

On diagrams and terminals, phase wires are signed with the Latin letter L; in multiphase networks, the phase number is next to it (L1, L2, L3). On cables with several phases they have different colors. This makes wiring easier.

How to determine if the wires are connected correctly

When trying to install an additional outlet, connect a chandelier, household appliances, you need to know which wire is phase, which is neutral, and which is ground. At incorrect connection equipment breaks down, and careless touching of live wires can end sadly.

You need to make sure that the colors of the wires - ground, phase, zero - match their wiring

The easiest way to navigate is by color coding of the wires. But things are not always simple. Firstly, in old houses the wiring is usually monochromatic - two or three white or black wires stick out. In this case, you need to understand it specifically, and then hang tags or leave colored marks. Secondly, even if the conductors in the cable are painted in different colors, and you can visually find the neutral and ground, you need to check the correctness of your assumptions. It happens that during installation the colors are mixed up. Therefore, first we double-check the correctness of the assumptions, then we begin work.

To check, you will need special tools or measuring instruments:

• indicator screwdriver;
• multimeter or tester.

You can find the phase wire using an indicator screwdriver; to determine zero and neutral, you will need a tester or multimeter.

Checking with indicator

Indicator screwdrivers come in several types. There are models on which the LED lights up when a metal part touches live parts. In other models, checking requires an additional button press. In any case, when voltage is present, the LED lights up.

Using an indicator screwdriver you can find the phases. Metal part touch the exposed conductor (press the button if necessary) and see if the LED lights up. Lit - this is a phase. Does not light - neutral or ground.

We work carefully, with one hand. Second to the walls or metal objects(pipes, for example) we don’t touch. If the wires in the cable you are testing are long and flexible, you can hold the insulation with your other hand (stay away from bare ends).

Checking with a multimeter or tester

We set the scale on the device, which is slightly higher than the expected voltage in the network, and connect the probes. If we call a household single-phase 220V network, set the switch to the 250V position. With one probe we touch the exposed part of the phase wire, with the second - to the supposed neutral (blue). If at the same time the arrow on the device deviates (remember its position) or a number close to 220 V lights up on the indicator. We perform the same operation with the second conductor - which is identified by its color as “ground”. If everything is correct, the readings of the device should be lower - less than those that were before.

If there is no color marking of the wires, you will have to go through all the pairs, determining the purpose of the conductors according to the indications. We use the same rule: when testing a phase-ground pair, the readings are lower than when testing a phase-zero pair.

Color marking of wires is far from being an advertising feature of manufacturers, as some novice electricians believe. This is a special designation that allows the electrician to determine zero, grounding and phase without the use of additional measuring instruments.

If the contacts are connected incorrectly, problems may occur. unpleasant consequences in the form of a short circuit and electric shock to a person.

The main purpose of applying color markings is to reduce the time required to connect contacts and create safe conditions when conducting electrical installation work. Currently, in accordance with the PUE and European standards, each core has its own clearly defined color.

We will talk about what color the neutral wire, grounding and phase have.

Ground wire

According to standards, ground insulation is colored yellow-green. Some manufacturers apply yellow-green stripes in the longitudinal and transverse directions to the grounding conductor. Rarely, but still found, the shells are purely green or purely yellow.

On electrical diagrams“earth” is denoted by two Latin letters “RE”. Grounding is often called zero protection, but it is not a working zero and should not be confused.

Neutral wire

Both in a single-phase electrical network and a three-phase one, the neutral is painted blue or blue. On the electrical diagram, zero is indicated by the Latin letter “N”. Neutral is also called zero or neutral operating contact.

Phase wire

Depending on the manufacturer, this wire is marked with the following colors:

• white;
• turquoise;
• black;
• brown;
• pink;
• red;
• violet;
• orange.

The most common colors to indicate phase are black, white and brown.

Despite its apparent simplicity, color marking has a number of features that raise the following questions for beginners:

1.What is PEN?

2.How to determine phase, ground and zero if the insulation has custom color or completely colorless?

Let's look at each point.

What is PEN?

The TN-C type grounding system, which is outdated today, involves combining grounding and neutral. Its main advantage is the speed of electrical installation work. The disadvantage of TN-C is the high probability of electric shock damage when installing wiring in an apartment or house.

The main color to indicate the combined wire is yellow-green, but at the ends of the insulation there is a blue color characteristic of the neutral wire.

On the electrical diagram, such a contact is designated by three Latin letters “PEN”.

How to find phase, ground and zero?

There are times when, when repairing a household electrical network, it turns out that all the conductors are the same color. In this case, how can you determine which wire is which?

In a single-phase network, where there are only two wires, without grounding, you just need to have a special indicator screwdriver with you. First you need to turn off the electricity at the distribution panel. Then the wires are stripped and routed to the sides. Now turn on the electricity again and bring the indicator to each of the wires one by one. If the light on the screwdriver lights up upon contact, it means it is a phase, and the second wire is, therefore, zero.

If electrical network three-phase, then you will need more complex equipment - a multimeter with measuring probes. First, set the device to a value above 220 Volts. We fix one probe on the phase, and with the second we determine grounding and zero. When contacting zero, the tester should show a voltage of 220 Volts. The ground wire will show a slightly lower voltage.

If you don’t have an indicator screwdriver or a multitester at hand, you can determine the identity of the wire by looking at the insulation. The important thing to know here is that the blue shell is always neutral. Even with the most non-standard markings, its color does not change. The other two wires are more difficult to install.

The first method is based on associations. For example, in front of you is a colored and white or black contact. Typically, land is designated white or black. Therefore, the remaining wire is a phase.

Second way. We discard the neutral again. All that's left is red and black. According to the PUE, white insulation is a phase. Then the red conductor is the ground.

In chains with DC The color marking of minus and plus is represented by black and red insulation, respectively. In a three-phase transformer network, each phase is painted in an individual color:

• A-yellow;
• B-green;
• C-red.

Zero, as always, is blue, and ground is yellow-green. In cables designed for a voltage of 380 Volts, the wires are designated as follows:

• A-white;
• B-black;
• C-red.

Protective and neutral conductors do not differ in markings from the previous version.

We designate the wires ourselves

If there is no visual indication, after repair work You need to independently indicate the identity of the wires. Brightly colored insulating tape or heat shrink tubing is suitable for this purpose.

According to GOST, core markings must be carried out at the ends of the conductors - at the points of their contact with the bus.

Such notes will make it much easier future renovation and service.

Carrying out electrical installation work is a rather complicated task, which is best left to a specialist in this field. However, if you need to purchase cords, wires and various cables for installation, you need to understand their markings. The indication on the insulation of the products with an alphanumeric code is the marking of the wires.

IN present moment Each manufacturer designates its products with codes so that any consumer, looking at it, can understand what the product is made of, what the rated withstand voltage is, the type of cross-section, as well as its design features and type of insulation.

To comply with these parameters, all factories and enterprises engaged in the manufacture of electrical products are required to use international standard- GOST. Marking the wires also allows you to special effort determine the location of the phase, zero, and in some cases, grounding. Let's look at the main electrical products on the market.

Cables

Electrical cables come in several types depending on the purpose of use. They may also consist of copper or aluminum strands, which are collected in bundles under one or different winding materials of plastic or PVC. There is also sometimes an additional protective shell made of steel tape.

Depending on the application, the color coding of the wires may also vary. So, they distinguish:

• RF cables that transmit radio and video signals.
• Controls for transmitting a signal to one or another device.
• Power cables are used in lighting fixtures for transmitting electricity. Can be used in both internal and external electrical wiring.
• To transmit communications, cables are used that can conduct current of different frequencies.
• Automation systems use control cables that are copper conductors, located under a protective screen that removes interference and prevents mechanical damage.

Wires

A product formed from several wires or only one is called a wire. In most cases, the winding is plastic, less often wire, but it is also found without insulation at all.

At the moment, greater preference is given to wires whose cores are made of copper or aluminum. Such products are used not only in electrical installation work, but also as windings for electric motors.

They have a low cost, but a huge disadvantage is the impossibility of connecting them with others, for example, copper ones. Copper products can withstand loads well, but in the open air they quickly oxidize and are expensive.

Marking electrical wires also depends on their purpose. Installation and power are used both indoors and outdoors. Assembly ones, in turn, are used when assembling electrical circuits in switchboards or radio equipment.

Cords

The cord consists of several strands with a small cross-section, which consist of many intertwined wires. Most often, this electrical product is represented by multi-core cords, the winding of which is non-metallic.

The main use of cords is for connecting industrial and household appliances to the network.

Letter marking

Any electrical product must be marked in accordance with GOST standards. The first letter indicates the material from which the core is made. If it is copper, the letter is not assigned, if it is aluminum, then it is marked with the letter “A”.

Explanation and wires The second letter characterizes the type or material of insulation. Depending on the type of wire, it can be written as “P”, “M”, “MG”, “K”, “U”, which corresponds to flat, mounting, mounting with flexible cores, control and installation types of wire. The installation one can also be marked as “P” or “W”.

The next, third letter, means the material of the winding of the product:

• “K” - nylon;
• “C” - fiberglass;
• “BP” or “P” - polyvinyl chloride;
• “F” - metal;
• “E” - shielded;
• “R” - rubber;
• "ME" - enameled;
• “T” - winding with a supporting torso;
• “NR” or “N” - nayrite;
• “L” - varnished;
• “G” - winding with flexible core;
• “O” and “Sh” - polyamide silk as braiding or insulation.

Wire markings may also have a fourth letter, which characterizes design features electrical product:

• “K” - the wire is armored with round wires;
• “A” - asphalted wire;
• “T” - the product is used for installation in pipes;
• “B” - armored with tapes;
• “O” - the presence of a protective braid;
• “G” - for wire - flexible, and for cable - without protection.

Digital marking

The marking of electrical wires by the first number indicates the number of cores; if it is missing, the conductor has only one core. The second and third digits mean in square millimeters and the rated withstand voltage of the network.

Grounding

For the most part, color coding of wires is intended to facilitate electrical installation work and ensure safety.

According to the ground conductor insulation, it should have a green-yellow color. In some cases, the color may be exclusively green or only yellow.

For grounding, wire color markings are applied either longitudinally or transversely. On electrical circuits, “ground” is usually denoted by the letters “PE”, which is also sometimes called zero protection.

Zero

The zero working contact does not carry a voltage charge, but is only a conductor. The color marking of the wires should be bluish or blue. On an electrical diagram, zero is usually designated as “N”.

Phase

The phase wire is always energized if it is connected to the network. Phase wire color marking can be done in many ways color shades- brown, black, turquoise, purple, gray and others. But most often phase conductors are white or black.

PEN conductor

In any residential building or premises, it is always necessary to ground or ground the electrical wiring. Currently, it is important to carry out a TN-C grounding system, which includes combining the ground and neutral wires. The color marking of wires combined using this system will change from yellow-green to blue.

First, you need to divide the conductor into two buses - PE and N, which are subsequently connected to each other by a jumper in the middle or two at the edges. Then re-ground the PE bus and check the resistance.

How to determine the phase?

Sometimes during electrical repairs or upgrades, it is necessary to determine which wire means what. But it happens that marking wires by color does not help in this, since due to a long service life or in the event of a short circuit this is not possible.

This task can be dealt with using an indicator screwdriver, popularly called a “control”. This method is suitable in the case of a single-phase network, without a ground wire. First you need to turn off the electricity supply, move both conductors apart and turn them on again. After that, bring the indicator screwdriver to one of the wires. If the light on the “control” lights up, then this wire will be a phase, and the remaining wire will be a zero.

If the wiring is three-wire, you can use a multimeter to determine each of the wires. This device has two wires. First you need to set it to a rated voltage of over 220 Volts. After that, fix one of the multimeter wires in contact with the phase, and use the other to determine grounding or neutral. If the second wire detects a grounding conductor, the readings on the device will drop slightly below 220, and if zero, then the voltage will shift within 220 Volts.

The third method of identifying wires can be used if you don’t have a screwdriver or a multimeter at hand. Marking the wires can help with this; in any situation, to isolate the zero, they will be marked in a blue-blue color scheme. The remaining two contacts will be more difficult to determine.

If one of the contacts is colored and the other is white or black, then most likely the colored one will be phase. By old standards black and white designated the grounding conductor.

Also, according to the rules for installing electrical equipment, white color The ground wire is marked.

Marking in DC circuit

The marking of wires in a DC network has red insulation color for positive, and black for negative. If the network is three-phase, then each phase will have its own specific color: red, yellow and green. Zero and ground, as usual, will be blue and yellow-green.

If a cable is inserted, the phase wires will have black, white and red insulation, and the color of the neutral and ground will remain unchanged, as is the case with a 220-volt network.

Independent wire designation

Sometimes, in the absence of a suitable color, you can independently change the color of the same wire used for neutral, phase and ground. In this case, decoding the wire markings will be very useful.

You can make small notes on the wires, which can be very useful later. You can also use colored electrical tape and wrap the wires in accordance with the markings.

To date in great demand They use cambrics, which are colored plastic tubes that can be heat-shrinkable. If busbars are used, it is also necessary to mark the ends of the conductors.