EMI literal translation is the electromagnetic interference. This is a compound word, we should respectively consider “electromagnetic” and “interference”.
“Interference” refers to performance reduced of equipment after suffered the disturbance and interference sources of equipment produced interference. So EMI standards and EMI test are which parts of EMI? Of course the answer is the interference sources.
The second is “electromagnetic”. If the electric charges are static, that’s called static electricity. When different electric potentials move to consistent direction, so occur electrostatic discharge, produce electrical current, and produce magnetic field around the current. If the direction and size of current change consistent then produce electromagnetic wave. EMS literal translation is “electromagnetic sensitivity”. It is refers that due to the electromagnetic energy cause the performance degradation’s easily degree.
EMC literal translation is “Electromagnetic Compatibility.” Means of electromagnetic energy generated by the equipment is neither interfere to other equipments and nor accept the electromagnetic energy interference of other equipment. Therefore, EMC includes two aspects: On the one hand, it is refers to the equipment in normal operation process towards the environment in which the electromagnetic interference cannot exceed a certain limit; On the other hand refers to the equipment in environments where electromagnetic interference immunity, means electromagnetic sensitivity.
In fact, the EMC contains EMI (electromagnetic interference) and EMS (electromagnetic sensitivity) two aspects.