The basic structure of a power cable consists of four parts: the core (conductor), the insulating layer, the shielding layer and the protective layer. The wire core is the conductive part of the power cable, which is used to transmit electrical energy and is the main part of the power cable. The insulating layer is to electrically isolate the core from the ground and the cores of different phases from each other to ensure the transmission of electric energy, and is an indispensable part of the power cable structure. Folded shielding layer, power cables of 15KV and above generally have conductor shielding layer and insulating shielding layer. The role of the protective layer is to protect the power cable from the intrusion of external impurities and moisture, and to prevent the power cable from being directly damaged by external forces.
The rated voltage U0/U(KV) is: 0.6/1, 1.8/3, 3.6/6, 6/6, 6/10, 8.7/10, 8.7/15, 12/20, 21/35, 26/35. The maximum working temperature of the conductor is 90°C, the short-circuit temperature (the longest duration is 5S) ≤ 250°C, when the ambient temperature is ≥ 0°C during laying, (preheating is required below 0°C) ≥ 0°C when laying is allowed to bend the radius of single-core cables, and more The core cable is not less than 15 times the outer diameter of the cable ≥ 15, and the flame retardant properties conform to GB12666.5A, B or C (IEC332-3).