Back to overview

Conductors and cables

Conductors and cables with wire marking

Conductors, cables, and wiring all serve the same purpose: to carry electrical signals or energy.

In everyday conversation, cables are often equated to wires, as both versions generally consist of several conductors that are isolated from each other. Cables, however, have increased mechanical resistance, which allows use in the ground, underwater or even unprotected outside. The conductor (also called wire) consists of a conductive core of copper or aluminum, in addition to insulation. Copper is preferred, due to its excellent electrotechnical properties.

Conductor classes according to IEC/DIN EN 60228

Conductors divided by class  

Conductor classes according to IEC/DIN EN 60228 (VDE 0295)

The IEC / DIN EN 60228 (VDE 0295) divides conductor into four classes of flexibility, which classifies the basic flexibility of the conductors. The criteria for this are the individual wire diameters and the number of individual wires. A further influence on the inherent stability is the twist pitch. The twist pitch refers to the length of an individual wire, that is required for a 360° rotation. The lower the twist pitch, the more rigid and compact the conductor is. This also increases the external diameter.

  • Class 1: single-strand    
  • Class 2: multiple strand
  • Class 5: fine-strand
  • Class 6: extra-fine-strand
Standard conductor structure  

Standard conductor structure

In the IEC/DIN EN 60228 (VDE 0295) standard, the conductor cross sections are defined by the electric conductance or resistance values. These values are the basis for determining the maximum current carrying capacity. Geometrical data, in particular cross section tolerances, are not determined here. As a result, the actual cross section can deviate substantially from the nominal cross sections.

By using copper, which today has a purity of up to 99.99%, the manufacturer is in a position to replace the actual copper cross section with one of more than 10% less. This factor presents a challenge when it comes to crimping.

The insulation serves as a permanent divider between the individual conductors as well as a protective casing against external influences. The basic requirement from the insulation material is the greatest possible electrical resistance; however, the corresponding resulting warmth can detract from this. Today, the choice of insulation is above all plastic, in all its versions. The type and properties of the plastic decide the later usage options for the conductors, cables, and wires. A further criterion is the strength of the insulation. This measure has direct influence on the mechanical and electrical loading capacity. The condition of the insulation (hardness, durability, thickness, etc.) is furthermore decisive when choosing the right stripping tool.

  1. Insulation
  2. Conductor
  3. Stripping length
  4. Litz wire
  5. Twist direction
  6. Twist pitch
Description Language Updated
Table for conductor pull-out force per cross section [PDF, 34 KB] english 25.03.2017

Back to overview
General information


C6 The Exchange
Calmount Park
Dublin 12
D12 XE18