When do we use conductor colours?

Jan Arnoldy | 28. April 2020

Clear, correct conductor colours are very important so that the individual cores can be identified precisely. The correct conductor colours help electricians connect cables correctly and avoid errors.

If we take a closer look at cores and cables, we discover that they use conductor colours. These colours are not always the same. When do we use which conductor colours?

Conductor colours

The colours of the individual cores depend on the various types of cables.

Many people are familiar with the commonly used conductor colours from building cabling. So-called NYM cables are often used to supply sockets and light switches with power.

The cables employed in buildings use standardised conductor colours according to DIN VDE 0293-308

Conductor colours for motor cables and control cables

Conductor colours are different for motor cables and control cables in industry and industrial applications.

There, cores with cross sections greater than 0.5mm² are black with white numbers, and there is also a green/yellow protective earth (PE). The primary concern in assigning the protective earth colour is conspicuousness. This allows it to be easily distinguished from the other cores.

Conductor colours for data cables

Conductor colours for chainflex data cables are according the DIN 47100. The DIN 47100 colour code is used to clearly differentiate cores and contains a defined sequence of colours.

To distinguish a number of cores or individual core groups in a cable even more clearly, coloured rings are added to the cores at defined intervals.

This is especially important for cores with cross sections of less than 0.5mm². The individual colours are easier to identify than numbers when cross sections are small.

Core designation for measuring systems and bus cables

For these two cable types, there is no single simple explanation for core designations. Designation varies according to specification. The reason is that each bus standard established a colour code individually when the bus system was developed.

These colour codes are the same all over the world for the bus systems. Examples of bus systems include CC-Link, Profibus, Profinet, CAN-Bus, Ethercat and Ethernet.

Here are a few examples of different bus cables:

left: Profinet; right: Profibus

In measuring system cables, designation varies from system to system. It is established by each measuring system manufacturer individually and standardised globally.

A well-known example of a measuring system is the Siemens DRIVE-CLiQ:

At igus, we manufacture our cables precisely according to manufacturer measuring system information and mark it accordingly.

Do you have any questions? Feel free to contact us.