What's the power cable shielding layer for?
The use of a power cable shield
Shield to uniform conductive wire core and electric insulation, 6 kV and above in high voltage power cables have commonly conductor shielding layer and the insulating shield, part of the low voltage cable shielding layer. The shielding layer has two kinds of semiconduction shielding and metal shielding.
1. Conductive shielding and conductive shield are usually set on the outer surface of the conducting wire core and outside surface of the insulating layer, called the semiconduction shielding layer inside and outside the semiconduction shielding layer.
The Semiconduction shielding layer is made up of low resistivity and thickness of thin semiconducting material. Semiconduction shielding layer is for the sake of uniform line within the core outside the surface electric field, avoid the conductor surface is not smooth and twisted line core air gap produced by the conductor and insulation caused by the partial discharge. Semiconduction shielding layer and insulating layer outside the surface contact are very good, and the potential and metal ferrule, avoid the cable insulation defects such as surface crack and partial discharge with a metal sheath.
2. The metal mask For no metal sheathed in low voltage power cables, in addition to setting a semiconduction shielding layer, and increase the metal shielding layer. Metal shielding layers are usually made of copper or copper wire around the package, and mainly have the effect of shielding the electric fields.