What color are the wiresThe wires in the wiring are color-coded, which allows an electrician to quickly find zero, phase and ground. If these contacts are connected to each other incorrectly, a short circuit may occur, and in some cases a person is struck by an electrical current. Therefore, color marking of wires creates a safe environment for electrical work, and in addition, significantly reduces the time to search and connect contacts. Currently, according to the rules of electrical installations (PUE) and the necessary European standards, each wire must have its own specific color.


  • 1 What are colored wires for?
  • 2 What does a ground wire and zero look like?
  • 3 How does the wire phase
  • 4 How to distinguish between zero and "ground"
  • 5 How to determine the phase
  • 6 Conclusion

What are colored wires for?

Specific colors in electrics chosen by chance. Color wiring is required for safe electrical work to avoid short circuits and electric shock. Before the color of the conductors was black or whiteAs a result, electricians brought great inconvenience. When disconnected, it was necessary to supply power to the conductors, after which the zero and phase were determined using control. The use of colors has relieved all these torments, because everything has become very clear.

Color markings are almost always applied along the entire length of the conductor. It helps to set the destination of each conductor to a specific group in order to facilitate their switching. There are three types of wires in electrics: phase, zero and ground.

What does a ground wire and zero look like?

According to PUE, ground wire has the following colors:

  • yellow green;
  • yellow;
  • green.

You should be aware that manufacturers also apply yellow-green stripes on such a conductor in the longitudinal and transverse directions. On the wiring diagram, grounding is denoted by Latin letters "PE". Quite often, grounding is called zero protection, and it should not be confused with zero working.

In single-phase and three-phase mains wire zero is usually indicated by blue or blue-white color. On the wiring diagram, zero is indicated by the Latin letter “N”. Zero is also called neutral or zero working contact.

How does the wire phase

Marking the phase wire (L) is presented in the following colors:

  • Wire color and significance determinationthe black;
  • Gray;
  • brown;
  • Violet;
  • turquoise;
  • white;
  • red;
  • Orange;
  • pink.

But most often the phase conductor has brown, white and black.

How to distinguish between zero and "ground"

Zero differs from grounding by the fact that electrical current flows through it during connection of the load, and the “ground” used to protect against electric shock, which does not leak through this conductor, and is connected to the enclosures devices.

Wires "earth" and zero can be distinguished in the following ways:

  • Using an ohmmeter, measure the resistance on the "earth" conductor (which usually does not exceed 4 ohms). Before this, you should make sure that there is no voltage between the measurement points.
  • Using a voltmeter, one by one measures the voltage between the phase conductor and the two remaining wires. In this case, the "land" always has great value.
  • If it is necessary to measure the voltage between the “ground” and any grounded device (for example, a central heating battery or a switchboard housing), then the voltmeter shows absolutely nothing. And if the same way to apply to zero - there will be a small voltage.

If the wiring has only 2 wires, it will always be a phase and zero.

How to determine the phase

Phase definitionIf you need to install or replace the outlet, it is not necessary to determine the phasebecause it absolutely doesn't matter which side of her connect. It is quite another matter with the switch from chandeliersbecause it is necessary to submit to it exactly the phase, and to lamps - only zero.

If the color of the wires, phase zero is exactly the same, then the conductors are determined using an indicator screwdriver, in which the handle is made of transparent plastic, and inside is installed diode. Before determining the conductors, the room or house is de-energized, the wiring at the ends is stripped and divorced to the side, otherwise they may accidentally touch and short circuit will occur.

Thereafter connect electricity, take the screwdriver by the handle, and the index and thumb put on contact with the back of the outlet. Then it is necessary to touch the bare end of the screwdriver to the bare wire and to follow its reaction. If the bulb lights up, it means that it is a phase, if not - zero. However, such a screwdriver will not be able to identify the conductors, if there is a third wire - ground.


The use of color markings in electrics made life easier for people who, for various reasons, need to know which wires are live. However, you still need to be careful when working with electricity, so that later there will be no sad consequences.