Cable eccentricity counts
(...and is measured)

What is cable eccentricity?

In cables, eccentricity is the distance between the center of the copper conductor and the center of the insulation. The perfect eccentricity is 0mm, i.e. the center of the conductor coincides perfectly with the center of the insulation.

Why is good eccentricity important?

Good eccentricity ensures that the cable will perform reliably and will have the characteristics it was designed for.

Poor eccentricity, however, can adversely affect both electrical and mechanical characteristics of the cable

While the outside diameter of the insulation may be correct, poor eccentricity changes the distribution of the magnetic and electric fields, and modifies fundamental cable parameters such as capacitance and inductance. As a result, signal losses may increase, electromagnetic shielding may deteriorate, and insulation resistance and voltage withstand may be greatly reduced.

Furthermore, poor eccentricity downgrades cable's structural stability and compromises its ability to successfully withstand the mechanical stress and bending during the installation.

How do you measure eccentricity at Accordia?

On a produced cable sample,  eccentricity is measured with the help of a stereoscope and measuring software

But the most important thing is to be able to know the eccentricity on-line during the manufacturing process. For this reason, at Accordia we use special equipment (see photo at the top of the page) that monitors eccentricity continuously, without cable contact and gives real-time measurements on a screen and in the central data acquisition system. This is how we ensure that every millimeter (literally) of our produced cable is within our strict eccentricity manufacturing limits.