Search results
Results From The WOW.Com Content Network
Conducted EMI is caused by the physical contact of the conductors as opposed to radiated EMI which is caused by induction (without physical contact of the conductors). For lower frequencies, EMI is caused by conduction and, for higher frequencies, by radiation. EMI through the ground wire is also very common in an electrical facility.
Electromagnetic compatibility (EMC) is the ability of electrical equipment and systems to function acceptably in their electromagnetic environment, by limiting the unintentional generation, propagation and reception of electromagnetic energy which may cause unwanted effects such as electromagnetic interference (EMI) or even physical damage to ...
Another example of the practical use of electromagnetic shielding would be defense applications. As technology improves, so does the susceptibility to various types of nefarious electromagnetic interference. The idea of encasing a cable inside a grounded conductive barrier can provide mitigation to these risks.
In electronics, a choke is an inductor used to block higher-frequency alternating currents (AC) while passing direct current (DC) and lower-frequency ACs in a circuit. A choke usually consists of a coil of insulated wire often wound on a magnetic core, although some consist of a doughnut-shaped ferrite bead strung on a wire.
Ferrite beads prevent electromagnetic interference (EMI) in two directions: from a device or to a device. [1] A conductive cable acts as an antenna – if the device produces radio-frequency energy, this can be transmitted through the cable, which acts as an unintentional radiator. In this case, the bead is required for regulatory compliance to ...
This type of shielding helps prevent EMI from entering or exiting the cable and also protects neighboring pairs from crosstalk. An early example of shielded twisted-pair was IBM STP-A, which is a two-pair 150 ohm S/FTP cable defined in 1985 by the IBM Cabling System specifications, and used with Token Ring or FDDI networks. [7] [11]
A line impedance stabilization network (LISN) [1] is a device used in conducted and radiated radio-frequency emission and susceptibility tests, as specified in various electromagnetic compatibility (EMC)/EMI test standards (e.g., by CISPR, International Electrotechnical Commission, CENELEC, U.S. Federal Communications Commission, MIL-STD, DO-160 Sections 20-21-22).
In electronics, electric power and telecommunication, coupling is the transfer of electrical energy from one circuit to another, or between parts of a circuit. Coupling can be deliberate as part of the function of the circuit, or it may be undesirable, for instance due to coupling to stray fields .