Insulation is a crucial component of H.T. cables, providing electrical insulation to prevent current leakage and ensure the safety and integrity of the transmission system. Common insulation materials include cross-linked polyethylene (XLPE) and ethylene propylene rubber (EPR), both of which offer high dielectric strength and thermal stability, essential for withstanding the high voltages and operating temperatures encountered in high-tension applications.

To protect the conductor and insulation from environmental factors such as moisture, heat, and mechanical stress, H.T. cables are typically surrounded by layers of protective materials. These may include metallic shielding, such as aluminum or copper tapes, to provide electromagnetic shielding and reduce electrical interference, as well as outer sheaths made of thermoplastic or thermosetting compounds for additional mechanical strength and resistance to abrasion and chemical degradation.

H.T. cables come in various designs to accommodate different voltage levels and transmission requirements. For extremely high voltages, extra precautions are taken to minimize the risk of corona discharge and insulation breakdown, such as using special insulation designs and incorporating gas or oil-filled compartments to enhance dielectric strength.

In addition to traditional overhead transmission lines, H.T. cables are also used in underground and submarine applications, where they offer advantages such as reduced visual impact, increased reliability, and lower susceptibility to weather-related disruptions.

Overall, H.T. cables play a crucial role in the efficient and reliable transmission of electrical power, enabling the delivery of electricity over long distances while maintaining safety, stability, and environmental sustainability.