EMI / EMC
Electro Magnetic Compatibility
EMI stand for Electro Magnetic Interference, the property or electronics to radiate radio signal, generallly interfering with radio reception.
EMC stands for Electro Magnetic Compatibility, and describes the way electric or electronic apparatus behave (regarding Electro Magnetic aspects) in the presence of other equipment. EMC includes EMI and Susceptibility.
This discipline of EMC investigates the undesired emitted radio interferences (emissions), and unwanted susceptibility of electronics against Electro Magnetic fields. A number of associated phenomena , known to interfere with electronics in a similar way are also taken into consideration.
The goal of EMC is to create a situation where more than one piece of equipment can operate simultaneously in a common Electro Magnetic environment and avoid any mutual interference effects.
Effects to be taken into consideration as EMC are:
- Electro Magnetic fields (radio waves),
- Electrostatic Discharges (sparks),
- Fast impulses on supply and other leads (on/off switching effects),
- Lightning pulses on supply and other leads,
- Magnetic fields and their impact on electronic components,
- Common Mode Voltages and Currents on all cabling (radio signals),
- Mains Fluctuation and Harmonic Currents effects (mains pollution).
Reducing Interference, or noise mitigation and hence Electromagnetic Compatibility is achieved by addressing both emission and susceptibility issues. This is achieved by limiting the emissions of all electronic equipment, so as to enable communication receivers to operate in their vicinity, and likewise limiting the susceptibility of all equipment, so as to enable the operation of communication devices (transmitters) in their immediate vicinity.
Further reading
EMI EMC in Europe The Legal aspects
EMC tests our way of creating compliance
