What is electromagnetic protection?
Electromagnetic protection is an attempt to prevent electromagnetic interference in the electronic device. Electromagnetic waves that have an electrical and magnetic component can cause a failure of some devices in different ways. Metal walls can often be used to block electrostatic waves from the electric field. On the other hand, magnetic waves cannot be blocked and must be diverted around the object. Some materials can redirect the magnetic field lines around the device for this aspect of electromagnetic protection.
The first part of the electromagnetic protection is electrostatic protection. Protection against the outer electric field can be achieved with a metal box, often known as the Faraday cage. The Faraday Cages, named after English physician Michael Faraday, is a solid or network cover made of conductive material. When an external electric field reaches the walls of the Kradyský cage, electrons that act as carriers to cartridge fields. If the cage walls are ground orConnected to the outer conductive road, the electric currents in the walls are dispersed.
The Faraday Cage can also block the electric fields that are created in it. In fact, the microwave is a example of such an application. The microwave structure is made of conductive material, while the door is usually a metal network screen. Because the openings on the screen are smaller than the microwave wavelength - generally defined as between one millimeter and one meter - microwaves will not escape. For this reason, it is not recommended to remove the metal screen from the microwave.
Although the Faraday Cage can provide a lot of electromagnetic protection, it cannot block static magnetic fields - the second part of the electromagnetic wave. While the electrostatic waves are generates of stationary ammunition, magnetic fields are produced by moving charges. Electric currentIt is a collection of moving cartridges, so magnetic waves are often caused by electric currents around. Some electronic devices may be a problem with constant and slowly variable magnetic fields.
One solution for electromagnetic protection is the use of a shield that redirects the magnetic field line. Unlike the electrical fields, the magnetic field line must always return to its origin. Therefore, magnetic shielding does not attempt to stop the magnetic field lines; Rather, they try to avert them around the building. Materials that can be easily magnetized create good magnetic shields. Mu-metal-slit consisting mainly of nickel-is very effective but expensive material.