This test measures the degree to which the core conductor of a cable is off-center. In cable design, efforts should be made to ensure the conductive core of a cable is as centered as possible to ensure insulative uniformity throughout.
The sample’s outer layers are removed to the dielectric core of the cable. The thickness of the dielectric is measured very precisely (resolution of 0.0001 inch) at 45 degree increments around the sample. Of the measured thickness values, the thickest and thinnest measurement are used to mathematically determine the percent eccentricity of the inner conductor. To meet the requirements for this evaluation, the inner conductor displacement must not exceed 10% of the core radius.