XLPE is an abbreviated designation of “cross-linked polyethylene”.
Cross linked polyethylene is produced from polyethylene under high pressure with organic peroxides as additives. The application of heat and pressure is used to effect the cross linking.
An important advantage of XLPE as insulation for medium and high voltage cables is their low dielectric loss.
A layer of copper wires, applied over the extruded insulation screen, as a metallic screen, provides an earthed envelope.
The cross sectional area of this metallic screen is determined in order to satisfy the phase to earth fault level in the network.