The Facts About EMI


Electrically Conductive Gaskets

The Facts About Electromagnetic Interference (EMI)

  • Electromagnetic interference (EMI) is when electromagnetic energy from sources both internal and external affects equipment and the way it works. The performance of the equipment can be affected leading it to malfunction.
  • EMI can leave a source or enter vulnerable equipment through radiation, coupling, and conduction.
  • EMI is conducted via many sources. Antenna leads, power cables, ground connections, and signal lines are all potential ways for EMI to be conducted.
  • EMI is coupled between circuits, components, or equipment having mutual impedance through which voltages or currents in one circuit can cause voltages or currents in the other circuit.
  • Openings of any kind make equipment vulnerable to EMI being radiated through.
  • In order to reduce EMI, it is best to start by designing equipment so that it generates less EMI.
  • EMI can be contained within an enclosure by EMI shielding and EMI filtering.

EMI and Gasket Design

  • Gaskets are manufactured typically to seal the joints between mating surfaces that in turn prevent forcible penetration of the joint or seam.
  • Gaskets not only have to prevent fluids, vapors, and gasses from penetrating through but also EMI energy.
  • There are many materials available when it comes to gasket design, each one with a different purpose for the circumstances, which are faced.
  • When a gasket is installed and pressure is applied, the gasket conforms itself to the irregularities in both of the surfaces which seals the equipment.
  • When choosing which material to use for gasket design it is important to consider what temperatures the gasket will face as well as the chemical compounds which will be present.
  • During material selection of gasket design it is important to consider how many times the gasket will be taken off and reapplied throughout it’s life.