Materials

Relative permittivity

Conductivity (S/m)

Application

Copper

1

$\text{5}\text{.8}\times {\text{10}}^{\text{8}}$

Cable conductor

XLPE

2.3

$\text{1}\times {\text{10}}^{-15}$

Main insulation

Silicone Rubber

4.3

$\text{2}\text{.727}\times {\text{10}}^{-12}\times e^{9.796\times {\text{10}}^{-\text{6}}\times E}$

Joint insulation

Semi-conducting material

10

5, 10, 15, 20

Conductive layers and

stress cone