The basic structure of industrial control cable is as follows:
1. Conductor
It is the main component of the product to play its use function, and it is used to transmit power or information, that is, through current or electromagnetic wave on the conductor. Conductor is the basic and essential main component for the product to transmit current or electromagnetic wave information.
2. Insulating layer
It is a component wrapped around the periphery of the conductor and plays the role of electrical insulation. That is, it can ensure that the transmitted current or electromagnetic wave and light wave only travel along the wire and do not flow outward, and the potential on the conductor (that is, the potential difference formed on the surrounding objects, that is, the voltage) can be isolated, that is, it is necessary to ensure the normal transmission function of the wire and the safety of external objects and people. Wire and insulation layer are two basic components that constitute industrial control cable products. As for the varieties with only conductors but no insulation (such as ACSR, OCS conductor), in fact, it must be combined with external insulation (ground distance, space distance and insulator) before it becomes an overhead line. The names of these varieties are also slightly different, that is, they are called overhead "conductors", catenary "conductors", etc.
3. Filling structure
Many products are multi-core. After these insulated cores or pairs are cabled (or grouped into cables for many times), one is that the shape is not round, and the other is that there is a large gap between the insulated cores. Therefore, a filling structure must be added during cable forming. The filling structure is to make the outer diameter of the cable relatively round, so as to facilitate tape wrapping and sheath extrusion.
4. Shielding
It is a component that isolates the electromagnetic field in industrial control cable products from the external electromagnetic field. Some cable products also need to be isolated from each other between different wire pairs (or wire groups) inside. It can be said that the shielding layer is an "electromagnetic isolation layer". In the cable industry, it is usually used to take the shielding layer as a part of the protective layer structure.
5. Protective layer
It is a component that protects the whole product, especially the insulation. Because the insulating materials require excellent electrical insulation performance, the purity of the materials used is very high and the content of impurities is very small, so it is often unable to take into account its ability to protect the outside world. Therefore, the bearing or resistance of various external mechanical forces (i.e. installation and use occasions), resistance to atmospheric environment, resistance to chemicals, prevention of biological or harmful effects, and reduction of fire house hazards must be borne by various protective layer structures. Therefore, the sheath is a guarantee component for the long-term normal operation of industrial control cables under various external environmental conditions. If the industrial control cable is used in a good external environment, or its insulating layer material also has certain mechanical strength and weather resistance, it can have no protective layer.
