What is EMC ?
Ever wonder why you are requested to switch off your electronics devices when you are taking a flight? This is one of the typical case of EMC of which your electronics devices may interfere with the electronics system in the aircraft.
Electromagnetic compatibility is the capability of electrical and electronic systems, equipment and devices to operate in their intended electromagnetic environment within a defined margin of safety, and at design levels or performance, without suffering or causing unacceptable degradation as a result of electromagnetic interference.
As more electronics products e.g. hand phones radio transmitters, solid state switching devices, motor drives devices are developed and push to the market, the increase of electromagnetic pollution is on the rise everyday. These devices caused emissions to the environment where it was used.
As a result of these emissions, they will affect other electronic equipment which is susceptible to these emissions. As more microprocessors are used to replace analog or mechanical means of a product, it become apparent that the issue of EMC cannot be ignored. Ignoring this will caused the product to suddenly malfunction or even caused damage to properties or lives.
In order to ensure that the equipment are designed to perform as close as possible in its environment, the European standards making body CENELEC(European Committee for Electrotechnical Standardization) has been mandated to produce standards for use with the European EMC Directive. For telecommunications equipment ETSI(European Telecommunications Standards Institute)is the mandated standards body.
There are 3 types of standards :
a) Product or product family standards, relating to a specific product or product family group. The product standards take precedence over the generic standards and are drafted to cover the particular range of product types.
These standards should refer to the Basic Standards for test methods wherever possible. It wil consist of defining what tests to carry out, what levels or limits, and what operating conditions and performance criteria to apply. These are prepared by IEC, CENELEC or CISPR.
b) Generic Standards relating to a particular environment of use. At present these are for:
(i) Domestic, Commercial and Light Industry
(ii) Industrial environment
c) Basic Standards, to provide general information and relate to the disturbing phenomena and testing and measuring techniques. Basic standards do not contain limits or performance criteria. They serve as a reference for product standards and will not normally be listed in the Official Journal, but will be referred to in product or generic standards.
List of Product Standards related to household electrical appliances
i) EN 55014 Limits and methods of measurements of radio disturbance charateristics of household electrical appliances, portable tools, and similar electrical apparatus (CISPR 14).
ii) EN 55015 Limits and methods of measurement of radio disturbance characteristics of electrical lighting and similar equipment (CISPR 15).
iii) EN 55104 Electromagnetic compatibility - immunity requirements for household appliances, tools and similar apparatus (CSIPR 14-2)
Generic Standards - Emissions
i) EN 50081 Part 1 Generic emission standard, part 1: Residential, commercial and light industry environment.
ii) EN 50081 Part 2 Generic emission standard, part 2: Industrial environment.
Generic Standards - Immunity
i) EN 50082 Part 1 Generic immunity standard, part 1: Residential, commercial and light industry environment.
ii) EN 50082 Part 2 Generic immunity standard, part 2: Industrial environment.
i) EN 61000-3-2 Electromagnetic compatibility (EMC). Limits. Limits for harmonic current emissions (equipment input current up to and including 16 A per phase)
ii) EN 61000-3-3 Electromagnetic compatibility (EMC). Limits. Limitation of voltage changes, voltage fluctuations and flicker in public low-voltage supply systems, for equipment with rated current 16 A per phase and not subject to conditional connection.
iii) EN 61000-4-1 Electromagnetic compatibility (EMC). Testing and measurement techniques. Overview of IEC 61000-4 series.
iv) EN 61000-4-2 Electromagnetic compatibility (EMC). Testing and measurement techniques. Electrostatic discharge immunity test. Basic EMC publication.
v) EN 61000-4-3 Electromagnetic compatibility (EMC). Testing and measurement techniques. Radiated, radio-frequency, electromagnetic field immunity test.
vi) EN 61000-4-4 Electromagnetic compatibility (EMC). Testing and measurement techniques. Electrical fast transient/burst immunity test. Basic EMC publication.
vii) EN 61000-4-5 Electromagnetic compatibility (EMC). Testing and measurement techniques. Surge immunity test.
viii) EN 61000-4-6 Electromagnetic compatibility (EMC). Testing and measurement techniques. Immunity to conducted disturbances, induced by radio-frequency fields.
ix) EN 61000-4-7 Electromagnetic compatibility (EMC). General guide on harmonics and interharmonics measurements and instrumentation, for power supply systems and equipment connected thereto.
x) EN 61000-4-8 Electromagnetic compatibility. Testing and measurement techniques. Power frequency magnetic field immunity test. Basic EMC publication.
xi) EN 61000-4-9 Electromagnetic compatibility (EMC). Testing and measurement techniques. Pulse magnetic field immunity test. Basic EMC publication.
xii) EN 61000-4-10 Electromagnetic compatibility (EMC). Testing and measurement techniques. Damped oscillatory magnetic field immunity test. Basic EMC publication.
xiii) EN 61000-4-11 Electromagnetic compatibility (EMC). Testing and measurement techniques. Voltage dips, short interruptions and voltage variations immunity tests.
xiv) EN 61000-4-12 Electromagnetic compatibility (EMC). Testing and measurement techniques. Oscillatory waves immunity test. Basic EMC publication.
These listings are not exhaustive but cover the basics tests needed for household appliances. When performing compliance testing, one should verify which standards are mandatory for a product along with the required test levels and performance criteria.
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