A cable shielding is a cable that contains an insulated conductor wrapped in a standard conductive layer. The shield can be made of braided copper wire (or similar metal), spiral copper tape, or some other conductive polymer. The importance of cable shieldings cannot be overemphasized.
cable shieldings are usually thicker and stiffer than uncable shieldings. They also require more care when used. cable shieldings are most often found in industrial environments and installations where other equipment in the vicinity may generate electromagnetic interference (EMI).
Unshielded twisted pair cables do not have internal shielding to reduce EMI. instead, they are designed to eliminate EMI by using a pair of twisted pairs. these cables are light and thin, making them most suitable for indoor use in office environments for LAN or similar network cable systems. They are also less expensive than industrial cables. However, they are not always suitable for industrial environments that require large amounts of power or frequent use of heavy equipment.
What is the purpose of cable shieldings?
cable shieldings are used to protect data transmitted through the cable from electromagnetic interference, which is common in data centers, industrial environments, offices and other environments where computer technology, electrical equipment or electronic devices are used extensively.
EMI is generated by external sources and affects circuits through electrostatic coupling, conduction or electromagnetic induction. EMI interference can degrade the performance of a circuit or even stop it completely. As long as a data path exists, these effects can range from increased error rates to complete data loss. Both natural and artificial (man-made) sources can generate variable currents and voltages that cause EMI. Vehicle ignition and cell phones are prime examples of artificial sources of EMI. natural sources of EMI include electrical storms and the sun. EMI typically disrupts AM radios, TVs, and cell phones.
The shielding of cable shieldings reduces the volume and intensity of electrical noise, reducing its effect on signals and transmissions, as well as reducing electromagnetic radiation.
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