EMC electromagnetic compatibility refers to the ability that the equipment or system can meet the requirements in the electromagnetic environment

and does not produce unbearable electromagnetic interference to any equipment in the environment.

1、 Overview of EMC directive definition

EMC is the abbreviation of electrical compatibility. The definition of EMC in the International Electrotechnical Commission (IEC) standard refers to the ability

that the equipment or system can meet the requirements in the electromagnetic environment and does not produce unbearable electromagnetic

interference to any equipment in the environment. Among them, EMC includes EMI (electromagnetic interference) and EMS (electromagnetic immunity).

EMI means that the electromagnetic interference generated by the equipment in the normal operation process can not exceed a certain limit;

EMS means that the equipment has a certain degree of immunity to the electromagnetic interference in the environment, that is, electromagnetic sensitivity.

In order to standardize the management of electromagnetic compatibility of electrical equipment in EU Member States,

it is necessary for EU Member States to coordinate the laws and regulations on electromagnetic compatibility. 89 / 336 / EEC Electromagnetic Compatibility

Directive was issued on May 1, 1989 and implemented compulsorily on January 1, 1996. At present, the current directive is 2014 / 30 / EU.

2、 Similarities and differences between EMI and EMS in EMC directive

1. EMC includes EMI (interference) and EMS (susceptibility), namely electromagnetic interference and electromagnetic immunity.

2. EMI refers to the degree of electromagnetic interference, which describes the degree of electromagnetic radiation interference of a product to other products and whether it will affect the normal operation of its surrounding environment or other electronic and electrical products in the same electrical environment; EMI also includes conduction interference (CE), radiation interference (RE) and harmonic.

3. EMS, electromagnetic immunity, describes whether an electronic or electrical product will be affected by the interference of its surrounding environment

or other electronic or electrical products in the same electrical environment. EMS also includes electrostatic immunity (ESD), radio frequency immunity (EFT),

electrical fast transient immunity, surge immunity, voltage sag immunity (DIP) and other related items.

3、 Technical requirements of EMC directive

EMC EMC directive in the EU CE certification requires that all electronic and electrical products and equipment equipped with electronic and

electrical components should not emit electromagnetic waves beyond the specified limits, so as not to interfere with the normal operation of other equipment;

at the same time, it must have a certain anti-interference ability, so that the products can operate normally under normal conditions.

EMC Test is including:

1. conducted interference voltage

2. radiation field strength

3. interference power

4. antenna terminal interferes with telephone

5. harmonic current

6. fluctuation voltage

7. RF interference voltage

8. low frequency magnetic field

9. high frequency magnetic field

10. continuous interference

11. static electricity

12. transient pulse

13. RF continuous wave

14. continuous wave conduction interference

15. power frequency magnetic field

16. pulse

17. power voltage transients

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