International Standards and Conformity Assessment for all electrical, electronic and related technologies
Electromagnetic Compatibility

EMC

Electromagnetic Compatibility

 

Types of disturbances

Solving EMC problems, by limiting controllable emissions and by improving the immunity of susceptible devices or systems, involves trying to identify not only the susceptible equipment but also the source and the path of the disturbance between them. In practice, clear identification of the source or the path is often difficult and sometimes even impossible, but the way in which the source and device are coupled may be described as an effect resulting from a disruptive:

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  • an electric current or voltage
  • an electric field
  • a magnetic field
  • an electromagnetic field
  • some complex combination of the above

The IEC has classified these principal EM disturbance phenomena in six categories so that its technical committees can take a systematic approach towards preparing EMC International Standards for all kinds of products and systems. For example:

  • Conducted disturbances (harmonics, surges and electrical fast transients)
  • Radiated disturbances (electric and magnetic fields)
  • Electrostatic discharge (ESD)
  • Special high-power EM transients including nuclear high-altitude electromagnetic pulse (HEMP)