The following description is for the 10kV power cable.
The outermost layer of the 11kv power cable is generally rubber or rubber composite sheath. The function of this layer is firstly to insulate, but also to protect the cable from damage.
Power cables are divided into high voltage and low voltage cables. If it is high voltage, there will be a layer of resin-like filler inside, which serves as insulation. In high-voltage cables, this layer is the most important part of the insulation. The low voltage does not have this layer, and then there will be something like a ribbon wrapped inside, which is to fix each core of the cable and fill the gap in the middle.
The shielding layer is divided into two situations. The shielding layer of the 11kv power cable has two functions. One is because the current through the power cable is relatively large, and a magnetic field is generated around the current. In order not to affect other components, the electromagnetic field can be shielded in the cable by adding a shielding layer. Second, it can play a certain role in grounding protection. If the cable core is damaged, the leaked current can flow along the shielding layer like a grounding grid, which plays a role of safety protection.
Control cables are used in many places, especially the control cables of computer systems. The shielding layer here is used to shield external influences, because the current is very weak and it is very afraid of the influence of external electromagnetic fields.
The composition method of the power cable should be: conductive core, insulating layer, and protective layer. Detailed classification (not to mention high voltage and low voltage): conductive core, inner semiconducting layer, insulating layer, outer semiconducting layer, copper shielding, filler, inner lining, double steel belt protective layer, outer protective layer. The above description is for the 10kV power cable.