Usually, the voltage range of numerical high voltage cables is between 63 kV and 132 kV. These cables are produced in copper and aluminum types. The electric voltage in the cables of numerical transmission lines is between 230 and 500 kW and in Iran this number is between 230 and 400 kW.

High voltage copper cables or power cables are used to transmit electrical energy in systems with a nominal voltage higher than 30 kV from power plants to the central network or primary distribution networks. They are used as burial in the ground or inside the canal. The new high tension cable system is more suitable compared to the high tension cable overhead lines. New industrial methods have the ability to coordinate submarine high pressure copper cable with optical fiber and provide a flexible joint with a longer length than before.

High voltage copper cables use XLPE insulation which covers the conductor with CCV production line. XLPE insulation must have a completely uniform crystal structure without any impurities or defects. The internal and external semiconductor layers as well as the semiconductor tape are the difference between high voltage and low voltage cables as well as medium voltage cables.