EMC Consideration

Overview Of EMC

Electromagnetic interference is a serious and increasing form of environmental pollution. The large number of electronic devices in common use is partly responsible for this trend. Adopting the practices of electromagnetic compatibility (EMC) controls the pollution level of electromagnetic interference.

Definitions

•  Electromagnetic Compatibility (EMC):

Ability of a product, equipment, system to operate satisfactorily in, and not overly contribute to, an electromagnetic environment.

•Electromagnetic Interference (EMI):

Electromagnetic energy emanating from one device which causes another device to have degraded performance.

•Electromagnetic Susceptibility (Immunity) (EMS):

Ability to function properly in its intended electromagnetic environment. Tolerance in the presence of electromagnetic energy.

Simply put, EMC is to design equipment that  neither generates, nor is susceptible to, interference.

The performance level and requirement of Electromagnetic Compatibility (EMC) for any electronic product or system are specified by EMC regulations. These specified levels are enforced by individual country’s EMC regulations and standards. Failing to comply with these requirements can result in forced removal of a product from the marketplace, confiscation of non-compliant product, monetary fines, and in extreme cases, imprisonment.

Countries adopt different EMC Standards. Most adopt CISPR (International Special Committee for Radio Interference) as their national EMC regulation. In the US, the body responsible for EMC is FCC (Federal Communications Commission). For military applications, the EMC standard is MIL-STD-461E. These EMC Standards specifies what facilities to be used and how measurement are to be carried out.