Purpose of low-voltage shielded cable and shielded cable damage and prevention methods

In the manufacturing process of the shielding layer, there are many correct or incorrect processes, one of the most important parameters is the braiding angle of the shielding layer.

In cables used in energy chains, the load on the shield of the outer diameter of the cable must be taken into account. An unreasonable shield braiding angle will further increase the tensile load, resulting in shield breakage. As a result, the shielding effect is weakened, and when the sharp cable tail pierces the wool fabric or foil gold material and contacts the core wire, it can even cause a short circuit. Here, we recommend you a useful tip: if you peel off the insulation, you can easily push the shield back into the jacket, but such a shield cannot be used in energy supply systems, moving High flexible cable. Of course, igus is able to provide direct solutions to these problems:

The braiding angle of the shielding layer determined by long-term experiments can effectively offset the tension, so it is very suitable for drag chains.

Due to the stable inner jacket, the shield will not relax and fail. In stranded wire construction, the shield itself is resistant to torsion.

Worn or damaged sheath

Any defect in the internal structure is difficult to detect from the outside, but problems with the sheath are directly visible to the naked eye. The jacket is the first layer of protection for the delicate internal structure of the cable. This is why cracked, worn and expanded sheaths are very serious quality issues. To avoid such problems, igus offers seven different material cable jackets for users to choose according to the corresponding working environment of their machinery. A shielded cable is a transmission line that uses a metal mesh braid to wrap the signal wire. The braid is generally red copper or tinned copper. The wire and cable industry is the second largest industry in China after the automobile industry, and the product variety satisfaction rate and domestic market share both exceed 90%. Worldwide, China's total output value of wire and cable has surpassed that of the United States, becoming the world's largest wire and cable producer. With the rapid development of China's wire and cable industry, the number of new companies continues to rise, and the overall technical level of the industry has been greatly improved. Shielding is to ensure the transmission performance of the system in the environment of electromagnetic interference. The anti-interference here should include two aspects, that is, the ability to resist external electromagnetic interference and the ability of the system itself to radiate electromagnetic interference. In theory, wrapping a layer of metal material shielding layer on the outside of cables and connectors can effectively filter out unnecessary electromagnetic waves (this is also the method used by most shielding systems), however, the degree of effectiveness of this method How is it?

For the shielding system, it is not enough to have a metal shielding layer, and more importantly, the shielding layer must be completely grounded, so that the interference current can be effectively introduced into the ground. However, in actual construction, the shielding system has some difficulties that cannot be ignored: due to the strict requirements of the shielding system for grounding, it is very easy to cause poor grounding, such as excessive grounding resistance, unbalanced grounding potential, etc. There will be a potential difference between the two, and then the current on the metal shielding layer will be generated, causing the shielding layer to be discontinuous and destroying its integrity.

At this point, the shield itself has become one of the biggest sources of interference, resulting in far less performance than an unshielded system. When the shielded wire transmits at high frequency, both ends need to be grounded, which is more likely to generate a potential difference on the shielding layer. It can be seen that the requirements of the shielding system itself constitute the biggest obstacle to ensuring its performance. A complete shielding system requires shielding everywhere. Once the shielding at any point fails to meet the requirements, it will inevitably affect the overall transmission performance of the system. However, few network hubs or computers on the market have shielding support themselves, so it is difficult to shield the entire transmission link.

Armor Extruded Sheath

Manufacturing processes and materials are also important factors in determining product quality. In some so-called cables suitable for drag chains, the sheath is usually tubular, so it cannot provide the necessary support for the stranded structure during long-term bending, so that the stranded structure is prone to splitting. An armor-type extruded sheath. This jacket ensures that the cores of the cable do not loosen when the cable is in motion. The reason is that the sheath is extruded through a particularly large pressure, and it acts like a guide groove, which guides the movement of the core wire and also supports the movement of the core wire. Therefore, it is very suitable for energy chains.

Summarize the quality assurance of highly flexible cables suitable for drag chains: center stress relief design; multi-strand cabling structure; armor-type extruded inner sheath in shielded cables; fully shielded insulating braided mesh; optimized shielding braid angle ; Armor extruded sheath.