Wires red yellow green. Color marking of wires and cables. How phase wires are painted

Anyone who has ever dealt with wires and electrics noticed that conductors always have a different color of insulation. It's not just done. The colors of the wires in electrics are designed to make it easier to recognize the phase, neutral wire and ground. All of them have a certain color and are easily distinguished during operation. What is the color of the wires phase, zero, ground and will be discussed further.

How phase wires are painted

When working with wiring, the phase wires are the most dangerous. Touching the phase, under certain circumstances, can become lethal, which is probably why bright colors are chosen for them. In general, the colors of wires in electrics allow you to quickly determine which of the bundle of wires is the most dangerous and work with them very carefully.

Most often, phase conductors are red or black, but there is also another color: brown, lilac, orange, pink, purple, white, gray. Here in all these colors phases can be painted. It will be easier to deal with them if we exclude the neutral wire and ground.

In the diagrams, phase wires are indicated by the Latin (English) letter L. If there are several phases, a numerical designation is added to the letter: L1, L2, L3 for three-phase network 380 V. In another version, the first phase is denoted by the letter A, the second - B, the third - C.

Ground wire color

By modern standards, the ground conductor is yellow-green. It usually looks like yellow insulation with one or two longitudinal bright green stripes. But there are also coloring of transverse yellow-green stripes.

In some cases, only yellow or bright green conductors may be in the cable. In this case, the "earth" has exactly this color. It is displayed in the same colors on the diagrams - more often bright green, but it can also be yellow. Signed on the diagrams or on the equipment "earth" in Latin (English) letters PE. The contacts to which the "earth" wire must be connected are also marked.

Sometimes professionals call the ground wire "zero protective", but do not confuse. It is earth, and it is protective because it reduces the risk of electric shock.

What color is the neutral wire

Zero or neutral is blue or blue, sometimes blue with a white stripe. Other colors in electrics are not used to indicate zero. So it will be in any cable: three-core, five-core or with a large number of conductors.

In blue, they usually draw "zero" on the diagrams, and sign it with the Latin letter N. Experts call it the working zero, since, unlike grounding, it participates in the formation of the power supply circuit. When reading a circuit, it is often defined as "minus", while the phase is considered "plus".

How to check the correct labeling and wiring

The colors of wires in electrics are designed to speed up the identification of conductors, but relying only on colors is dangerous - they could be connected incorrectly. Therefore, before starting work, it is worth making sure that you have correctly identified their belonging.

We take a multimeter and / or an indicator screwdriver. It is easy to work with a screwdriver: when you touch the phase, the LED mounted in the case lights up. So it will be easy to determine the phase conductors. If the cable is two-core, there are no problems - the second conductor is zero. But if the wire is three-core, you need a multimeter or tester - with their help we will determine which of the remaining two phases, which is zero.

We set the switch on the device so that the jackal is more than 220 V. Then we take two probes, hold them by plastic handles, gently touch the metal rod of one probe to the found phase wire, the second to the supposed zero. The screen should show 220 V or current voltage. In fact, it can be much lower - these are our realities.

If 220 V or a little more is displayed, this is zero, and the other wire is presumably "ground". If the value is less, we continue the check. With one probe, we touch the phase again, with the second - to the intended ground. If the instrument readings are lower than during the first measurement, the “ground” is in front of you and it should be green. If the readings turned out to be higher, then somewhere they messed up with and in front of you “zero”. In such a situation, there are two options: look for exactly where the wires were connected incorrectly (preferably) or simply move on, remembering or noting the existing situation.

So, remember that when the phase-zero pair rings, the multimeter readings are always higher than when the phase-ground pair rings.

And, in conclusion, let me give you advice: when laying wiring and connecting wires, always connect conductors of the same color, do not confuse them. This can lead to disastrous results - at best, to the failure of the equipment, but there may be injuries and fires.

Individual wires-cores that make up electrical cables have insulation of certain colors. GOST R 50462-2009 regulates the color of insulation, this document shows the features of n and l marking in electrics in order to simplify the work of craftsmen at large facilities and ensure safety during the repair process. Those who decide to repair electrical appliances on their own or do other similar work should also know what color the ground, phase and zero wires are.

Features of the color of the cores

To avoid errors, the requirements of the PUE describe the colors of all the main electrical wires. If commissioning was carried out by an experienced electrician, following the rules PUE and relevant GOSTs, with self repair no indicator screwdriver or other devices that determine the purpose of a particular core are needed.

Color coding in electrics according to GOST

grounding

The yellow/green wire is ground. IN circuit diagrams neutral conductors are marked with the letters PE. In some houses of old buildings, there are PEN wires in which grounding is combined with a zero core. If the cable was pulled according to the rules, wires with blue insulation were selected, and only the ends and places of twists were yellow-green (thermotubes were put on them). The thickness of the "zero" and grounding can be different. Often the thickness of these two cores is less than the thickness of the phase core, this occurs when connecting portable devices.

When it comes to laying electrical wiring in multi-storey buildings and industrial premises, the PUE and GOST 18714-81 standards come into force, prescribing the mandatory arrangement of protective grounding. Grounding must have a minimum resistance in order to compensate for the consequences of faults on the line and prevent harm to human health. That is, compliance with the color marking standards for PUE wires is of paramount importance.

"Zero"

What color is the neutral wire? Electrical standards dictate that its insulation may be blue, blue with a white stripe, or light blue. Such a marking will be present in a cable with any number of cores. In circuit diagrams, "zero" is marked with the letter N, the circuit is closed on it. Sometimes it is called "minus", and phase - "plus".

"Phase"

The color of the phase is something that is of paramount importance for an electrician: handling conductors requires care and knowledge. The slightest touch of the phase can lead to injury. There are a lot of colors for phase wires marked in the form of the letter L in the wiring, the ban applies only to the use of blue, yellow and green colors. If the cable is three-phase, the serial number of the core is added to the letter L.

When a single-phase circuit is separated from a three-phase circuit, electricians use cables with exactly the same color, watching the color of the phase and zero in the wire. Before starting work, they determine for themselves how different cores will be connected, and in the future they follow the chosen color. Sometimes thermocambrics are fused on them or several turns of colored corresponding electrical tape are wound.

According to GOST:

• black phase wires are used in power circuits operating with constant and alternating current;
• red color - used in control circuits designed for alternating current;
• With Orange color- meet with interlock control circuits powered from external sources.

How to determine the purpose of the wire - neutral or ground?

L N marking in electrics is not always observed in old buildings, so the question arises of independently distinguishing between the neutral wire and the ground wire. When the circuit is closed, an electric current passes through the "zero". The grounding wire has only a protective function, and in the "normal" mode, the current does not flow through it.

You can find out whether it is “zero” or “ground” like this:

• Use an ohmmeter, having previously turned off the voltage between the measurement points. On the ground wire, the resistance will not exceed 4 ohms.
• Use a voltmeter and measure the voltage between the "phase" and other wires in series (the method is suitable for three-core cables). The ground wire will give the highest value.
• If the colors of the “phase”, “zero” and “ground” wires are unknown, and you need to find out the voltage between the ground wire and some obviously grounded object (for example, a heating radiator), a voltmeter will also come in handy. True, when connecting the "ground" and a grounded object, it will not show anything. But a small voltage will be reflected on its indicator if you do the same with the "zero" wire.

In a two-core cable, only the phase and neutral wires will always be present.

What to do if all the cores in the cable have the same color insulation

The question of marking wires by color does not make sense when you have to work with single-color cores - for example, when repairing wiring in old houses. For such cases, there are kits that make it possible to mark the cores. Areas for fixing marking devices are prescribed by the requirements of GOST, usually they are fixed next to the connection to the bus.

How to mark a wire with two cores

If all the wires in the cable have the same insulation, and the appliance is already connected to the network, the craftsmen use indicator screwdrivers. The latter glow when the metal part touches the phase wire. To mark a two-core cable, in addition to such a screwdriver, you will need thermocambrics or multi-colored electrical tape. The designation of colors will be made only at the joints - it is not necessary to wrap the core with colored tubes or electrical tape along the entire length.

Probe screwdriver-indicator

Phase wires can be marked with any color except blue, yellow and green. If a two-core cable is connected to a single-phase network, it is customary to mark the phase wire in red.

How to mark a wire with three cores

What is the color of the ground wire in a three-wire wire? If the answer to the question is not immediately determined, all the insulation on the cores of the same color will help out the multimeter. The device is set to alternating current, and the master sequentially touches both probes first with the phase wire, then with the rest of the wires, remembering the indicators. Touching phase and zero will give more voltage than touching phase and ground.

What color is the ground wire? It has a yellow-green color. It is this thermocambric or electrical tape that must be used to mark the "earth" in a three-core cable. On the “zero” - a blue tape should be wound, on the phase - not blue and not yellow-green thermocambric.

Letter designation of phase, zero and ground

The use of different colors of wires in electrical wiring is a convenient and logical measure that simplifies repair and installation work. If wires with multi-colored conductors are laid in the house, during the repair you will not have to spend time “ringing” each of them, and, for example, a break in the phase conductor will be detected quickly. The presence of a phase and zero also matters, but working with letters and numbers is still longer than with color: just look at the cable - and the purpose of the wires immediately becomes clear.

To facilitate the work of electricians, the release of cable insulation is subject to certain color marking standards. When connecting a multi-core cable, by the color of the polymer sheath, you can identify the core and understand with which contact it should be switched.

Different colors of wires in electrics, established by the provisions of GOST, help speed up the installation process and ensure electrical safety. Agree, an understanding of color coding is useful to every home master.

We offer to understand the designations of electrical wiring, learn GOST standards and learn how to read the letter codes of wires on the diagrams. In addition, we will tell you how to check the suitability of the connected core for its purpose using an indicator screwdriver or a multimeter.

The main document that you should rely on in the production of or is GOST 31947-2012. Before its appearance, there was no uniformity and order in the field of color designation of electrical wiring.

Until now, in old houses you can find wires in the same sheath, the color of which does not determine what is connected - “phase”, “zero” or “ground”.

Now it has become much easier to identify the veins. Even without using a tester, you can determine to which contact a particular core should be connected - by the color of the polymer insulation

The above-mentioned GOST document states that the insulation of cable products should differ in color. A certain shade should cover the wire with a continuous layer - from beginning to end. It is impossible for one wire at the beginning of the bay to be blue, and at the end white; intermittent coloring is also prohibited.

Content:

Many, when purchasing electrical wiring, do not even pay attention to the color of the insulation of the cores themselves. It seems to them that it is more profitable for an apartment to purchase an ordinary white product, without external insulation - because it is cheaper. But this is fundamentally wrong, because the color marking of the veins does not exist for beauty. Rather, the coloring of the insulation is a necessity dictated by safety and convenience.

For example, if the wiring was installed in accordance with the color marking of the cores, then in order to understand where the phase wire is, and where zero or ground is, a quick glance is enough, since there are not too many of them and it is easy to remember them.

The designations of wires by color, in addition to ease of installation, also ensure the safety of the electrician. After all, looking at the wire, you can already understand whether it is necessary to remove the voltage for repairs, or you can do without it.

Now let's try to understand what color the wires of the zero and ground phases are and how this can help in the work of not only an electrician, but also a home master.

What color is the ground wire?

The color of the ground wire, according to the European standard, is yellow with a green stripe. But in domestic veins, it can be solid yellow or solid light green. Here the designation by color plays very important role. The fact is that, provided that a residual current device (RCD) is installed in the power cabinet, from where the power is supplied to the room, then if you confuse the ground wire with zero, it will permanently turn off.

It makes sense to consider an example. A three-core automatic reclosure, popularly referred to as "noodles", comes from underground in a pipe. It is unrealistic for an electrician to understand which of the cores is zero and which is grounding, since both of them behave the same during testing. When connecting one contact of the control lamp to the phase, and the second to the ground wire, it will glow in the same way as when connected to the phase and zero.

This is the plus of a separate color marking of the ground wire. If in the same situation AVVG will come, for example, 3x2.5 (that is, a three-core cable with a cross section of 2.5 sq. mm), the electrician will not even have to get a test lamp or a multimeter (although you still need to check, because it is not known who and How did you connect). Everything will be clear by the colors, where is the ground of what color is the phase wire and so on. If the wire is yellow-green, then, subject to proper connection, it will be grounding.

Neutral wire in marked cable

The color marking of the neutral core in the cable is indicated by blue or light blue. There are also options for white insulation with a blue stripe, or a blue core with a white stripe. Schematic marking - "N", that is, neutral.

Also when installing blue wire or insulation of complementary colors do not come to switches or other breakers. They go from junction box directly to the lamp.

In distribution power boards, the incoming neutral wire comes to the neutral bus either directly, or through the machine, or from the meter. Further, all the wires of blue and blue colors from the cables outgoing to the room are connected to the same bus.

Of course, if the wiring was done by other people, you cannot fully rely on their attentiveness - as they say, trust, but verify. Therefore, you should check with the indicator whether there is voltage on this wire. But already in the apartment or in the room where the wiring was installed personally, such questions will not arise.

phase wire color

The color of the phase is represented by a wider range. The thing is that at a voltage of 380 volts, there are three opposite phases in the cable. And if there is a short circuit between them, that is, a short circuit of the phase voltage is much more dangerous than a short circuit of the linear voltage (phase wires with zero).

The color of the phase wires can be as follows: black, red, brown, gray, purple, pink, white, orange and turquoise color. In fact, it is necessary to remember only three colors in such markings. These are the colors that indicate the ground and zero, that is, the neutral wire. All other colors will be phase, that is, carrying a dangerous voltage.

And if suddenly mixed colors come to the introductory machine, then it is better to stick to the correct ones during further installation - you should not hope that the wrong colors are deposited in the memory. The best option would be in which further wiring will proceed in accordance with safety regulations. This will protect you from damage. electric shock when the phase wire comes into contact with the body (after all, the voltage of 220 volts is life-threatening, not to mention 380) and short circuits during subsequent additions of cables or revisions of the electrical installation of the apartment.

An interesting fact is that the color marking of non-insulated power buses in transformer and other power plants is slightly different from the marking of insulated wires. So, in the presence of three phases:

• Phase A - yellow color;
• Phase B - green;
• Phase C is red.

D.C

Of course, everyone is used to the fact that alternating current flows in the supply network of the apartment, but when installing networks direct current there are rules that govern the color marking of wires.

It is well known that there are no “phases” and “zero” in electrical wiring of this type. In this two-wire system, only "minus" and "plus" are present. The generally accepted color is a red “plus” wire and a blue “minus” wire. Sometimes a third light blue wire may be present. This will be the zero "M" contact. Provided that a cable with three cores and a cable with two are connected, the contact “M” that goes with “minus” and “plus” is excluded, and the rest are connected exclusively in accordance with the color.

Of course, in an apartment with such wiring you can only encounter during installation LED backlight, but still this information will not be superfluous.

What to do with incorrect labeling

Of course, if it is necessary to carry out wiring repairs or additional connections, it often happens that the marking of the cores does not comply with the rules. In this case, you need to stock up on colored electrical tape and, after ringing all the wires with a multimeter, mark in the immediate vicinity of the connection in order to subsequently understand what charge the line in front of your eyes carries. Knowing its purpose, there will be no need to call. Of course, it is not so easy to distinguish the neutral wire from grounding, but this is also possible.

Having found the phase wire with a screwdriver of the indicator and marking it with the desired color of electrical tape, you need to switch to working with a multimeter. By measuring the voltage alternately on the conductors, together with the phase, it is necessary to determine the deviations. The voltage between the phase and neutral core will always be higher than between the phase and ground.

By the way, for marking the ground wire for sale on the shelves of electrical stores, there is precisely yellow-green electrical tape. It will replace the yellow-green wire in the circuit.

Afterword

If it suddenly happened that during installation a violation of color marking was noticed, there is no need to repeat other people's mistakes and continue wiring without established rules. It is better to correctly mark the incoming veins, and then lead it according to the necessary colors. This method will save, subsequently, from the troubles and inconveniences associated with the revision, repair of wiring in the apartment and will significantly reduce the time spent on these actions. After all, it is much more convenient when the fitter knows what this or that designation means and is sure that you can not be afraid of the colors meaning grounding and zero, but you should be more careful with the red wire.

Everyone may face the need to repair electrical wiring or purchase various cable products for a future new home, and the color of wires in an electrician plays an important role. The reasons for this are different, but when you start to eliminate it, you should count on one encouraging factor that there is a color marking of wires. It is worth understanding what it is and why they do it.

Basic definitions

In AC power networks up to a thousand volts, the color marking of wires and cables is strictly regulated by state regulatory documents, such as the "Electrical Installation Rules" (PUE), namely, the section of the seventh edition in Chapter 1, paragraphs 1.1.29 - 1.1.30 is responsible for this. It states that "Identification of wire cores by colors or numerical designations" must be used in accordance with GOST P 50462-92 (IEC 446-89). Marking has the main designations:

In 3-phase AC switchboards, the busbars are painted:

• yellow - L1 (phase A);
• green - L2 (B);
• red - L3 (C);
• blue - block of the zero working conductor N;
• alternating longitudinal or transverse stripes of the same width of yellow-green color - PEN grounding bus.

Important! If the body of the electrical panel serves as a grounding contact at the same time, then the place of connection of the wires is indicated by the sign (ground) and is painted yellow-green.

The PUE allows you to designate the color of the main wires of the phase, zero not along the entire length of the bus, but only to perform at the points of connection to the contacts, if the bus is invisible, it is allowed not to color it.

Important! It is necessary to use the color marking of wires and cables when installing electrical equipment located in the same building with the same color schemes.

We must not forget that the designation of wires by color, in no case, should reduce the degree of electrical safety and convenience in the repair or maintenance of electrical equipment.

electrical safety

Alternating electricity with a voltage of 380V - 220V is a dangerous factor, so if an unauthorized person touches bare wires, or metal parts of electrical equipment that may be under this voltage, it can result in severe burns or fatal injury! 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.

In order to protect a person as much as possible from possible exposure to electric current, electrical safety systems were adopted, characterized by one or more factors, such as:

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

To provide safe work in existing electrical installations up to 1 kV, five grounding systems are used: TN-C, TN-S, TN-C-S, TT, IT with different ways grounding, zeroing and separation of networks. The PUE defines each of the systems as:

1. 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.
2. 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.
3. TN-C-S, where there is one combined PEN conductor of four-core cable, from the supply transformer to the 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.
4. 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, respectively, are used. Yes, basically arranged air lines power lines.
5. 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.

DC electrical networks

Along with alternating current, direct current circuits are used, for example, in on-board networks of cars and household appliances. In such wiring there is no phase wire and zero. The wire color rule in DC electrics is much simpler, since there are only two potentials positive, denoted by electrical diagrams, both (+) and negative, having a (-) sign. The colors of such wires are easy to remember: plus - red, and minus - black.

Important! For household appliances, these colors are correct only for supply lines; in the further part of the diagram, the positive wire may have a different color.

Practice

Starting directly to electrical work or repair in electrical wiring, you may encounter non-compliance with the color regulation, which is established by regulatory documents. As practice shows, this case is not the rule, but the exception.

Eg:

• you can buy a three-core cable type BBG 3x1.5, which has cores with white, red and brown colors;
• often found cable products with white wires with a color stripe of black, gray or of blue color, along the entire length;
• in the wiring that was done before, in general, you can find a two or three-wire white wire.

Here are some practical tips:

1. When repairing in existing networks, it is necessary to use electrical safety devices, such as a voltage indicator or an indicator screwdriver. With their help, you can always determine the color of the phase wire.
2. In the absence of the correct color coding for cable products, purchase a cambric or insulating tape of the required color. The main thing is to mark the color of the ground wire with a yellow-green color, the working zero - blue color, and for phase L in electrics, you can choose any other color.
3. When laying new wiring, use a cable of the same brand so that there is no confusion with the color of the wires in the electrician.

Color coding abroad

The yellow and green marker of the ground wire PE and the blue working zero N - are designated absolutely identically in all CIS countries, while they are clearly unified with the countries of the European Union. The color designation of the phase wire is somewhat different, but this is not of fundamental importance in terms of electrical safety.

Other countries such as Brazil, USA, Canada, Australia and New Zealand the PE ground wire, along with the yellow-green color, can simply be green, and the working zero N is designated by any of black, white or blue.

In the UK, Australia, New Zealand, Canada and the US, the PE conductor may not be insulated at all.

Important! Earlier in the USSR, according to the old edition of the PUE, there was a color marking that was fundamentally different from today. So, the dead-grounded neutral and all grounding conductors were designated in black, and White color wires corresponded to the working zero.

It is worth remembering that electric installation work require an electrician to have knowledge of electrical installations and safety precautions. Clearly knowing the marking, there will no longer be a question of how to choose the right wire color during operation, and repairing electrical wiring or installing equipment will become not only safe, but also convenient.

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