Wire colors in electrics: phase, zero, ground

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.

Coloring of phase wires

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 a three-phase 380 V network. In another version, the first phase is indicated 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.

This color can be grounding

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.

What color is the neutral wire? Blue or cyan

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.

Determining the phase wire with an indicator screwdriver

We set the switch on the device so that the jackal is more than 220 V. Then we take two probes, hold them by the 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.

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