Earth wire color in a three-phase network: international marking requirements

A grounding conductor connects an electrical device (or other metal structure) to earth, which has a negative electrostatic potential. Grounding is designed to drain current in the event of a breakdown on the device case.

The main task of the land tire is to protect the mechanism from destruction, and the person from injury. Therefore, when repairing or installing electrical networks, specialists must know the color of the earth.

Colored wires

In order for an electrical device to work, it is powered by an energy source. This is done using wires. To create a potential difference across the contacts, you will need at least two wires - zero and phase. For safe operation, a grounding bar is connected to the device.

Thus, phase, zero, ground must be connected to the electrical mechanism. The colors of the wires will indicate the purpose of each bus.

In the European Community, electrical conductors are color-coded in accordance with IEC 60445, adopted in 2010. On the territory of Russia, GOST 50462 of 2009 is in force, which fully complies with international rules.

Earth color

Modern standards require a ground bus in the network and a ground contact on the electrical device. It should be remembered that the manufacturer's warranty obligations apply only to devices that have a reliable connection to a grounded line.

The grounding cable is a yellow-green wire. Stranded wire painted yellow with a longitudinal green stripe. A single conductor conductor has a basic green background. There is a yellow line along the wire.

Sometimes there is a non-standard monochromatic color - yellow or green. According to the regulations of the International Electrotechnical Commission, the use of wires in this color version is prohibited.

On devices and wiring diagrams, "ground" is denoted by the Latin letters PE. The abbreviation corresponds to the English expression Protective Earth, which translated from English means “protected grounding”.

Phase vein

Any colors are used to paint the insulating layer of wires through which voltage is applied. The most commonly used are black, red and white., which, however, does not meet the requirements of technical standards.

In the diagrams, phase conductors are marked with the letter L. Experts decipher the meaning of the abbreviation in different ways. It can be Line, or Lead, or Live.

In networks with several busbars supplying current, each phase is designated by its own number (L 1, L 2, L 3). The color of the phases in three-phase networks can be any, with the exception of yellow, green and blue. However, European regulations establish clear color differences between phase conductors:

• L 1 - brown.
• L 2 - black.
• L 3 - gray.

If there are only three wires in the network, then the question arises about the color of the phase. A single phase 220 volt circuit uses a brown conductor.

Neutral marking

The neutral wire is painted in shades of blue. Rigid cable with one core has a dense ultramarine color. The easily bendable stranded conductor is covered with blue color insulation.

The neutral bus is designated N, which stands for Null, or Neutral.

Correct connection

When working with existing electrical networks, do not rely solely on the color difference of the conductors. Some amateur craftsmen do not take into account the coloring of cable insulation during installation. Experts recommend checking and determining the purpose of each wire. A screwdriver with an indicator and a multimeter will help you understand the electrical wiring.

With the help of an LED screwdriver, it is easy to find the phase conductor to which voltage is applied. The metal part of the device touches the bare end of the conductor. In this case, a special button is pressed. If the indicator is on, then it is a phase line. If the diode does not light up, then it is "ground" or "zero".

During operation, it is necessary to observe the following precautions:

1. Operations with a screwdriver are performed with one hand.
2. Do not touch walls or metal objects with your other hand to avoid electric shock.

It is convenient to ring the electrical wiring using a multimeter, which is equipped with probes with special clamps. Professionals call them "crocodiles" because of the resemblance to the jaw of an alligator.

Before working with a single-phase wiring with three lines, the tester is set up to measure voltage. The switch is set to 220 volts. The probes are applied to two different wires.

If the measuring device does not respond to touching the conductors, then this is a "zero" and "ground" line. One of the "crocodiles" is connected to a free wire. The multimeter will show the voltage, confirming the connection to "phase".

The next step is to define "neutral" and "ground". The probe on "phase" does not turn off. The free "crocodile" alternately closes the circuit in the remaining wires. The line where the tester reads more voltage is neutral. The other wire is grounded.

Multi-colored wires help to avoid mistakes when repairing and installing electrical circuits. Working with wires of different colors is faster. In addition, a variety of cable colors are more convenient for the electrician. It is much more pleasant to deal with conductors of different shades than to look at the interlacing of solid colored cables.