IEC 61000-4-14 pdf download – Electromagnetic compatibility (EMC) – Part 4-14: Testing and measurement techniques – Voltage fluctuation immunity test for equipment with input current not exceeding 16 A per phase
1 Scope
This part of lEC 61000 is a basic electromagnetic compatibility (EMC) publication. lt considersimmunity tests for electrical and/or electronic equipment in their electromagnetic environment.Only conducted phenomena are considered, including immunity tests for equipment connectedto public and industrial power supply networks.
This part aims to establish a reference for evaluating the immunity of electric and electronicequipment when subjected to positive and negative low amplitude voltage fluctuations.
The voltage fluctuations considered by this standard do not include flicker，which is aphysiological phenomenon due to lighting luminance fluctuations.
This standard applies to electrical and/or electronic equipment that have a rated input currentup to 16 A per phase. lt does not apply to electrical and/or electronic equipment connected tod.c. or a.c. 400 Hz distribution networks. Tests concerning these networks will be covered byother IEC standards.
The immunity test levels required for a specific electromagnetic environment，together with theperformance criteria，are indicated in the product，product family or generic standards asapplicable.However，most product groups do not have a history of being susceptible to voltagefluctuations.Consequently, testing for these phenomena is often not required.
2Normative references
The following referenced documents are indispensable for the application of this document. Fordated references,only the edition cited applies.For undated references, the latest edition ofthe referenced document (including any amendments) applies.
lEC 60050(161)，International ElectrotechnicalVocabulary (IEV) – Chapter 161: Electro-magnetic compatibility
IEC 60068-1，Environmental testing – Part 1: General and guidance
IEC 61000-2-4，Electromagnetic compatibility(EMC) – Part 2: Environment – Section 4:Compatibility levels in industrial plants for low-frequency conducted disturbances
General
3.1 Effects of voltage fluctuations
Electrical and electronic equipment may be affected by voltage fluctuations. Examples of theseeffects include the following:
degradation of performances in equipment using storage devices (e.g. capacitors);
– loss of function in control systems;
– instability of internal voltages and currents in equipment;
– increased ripple.
3.2 Sources
There is a significant number of domestic appliances in the low-voltage network. However,fluctuations caused by these appliances are not generally significant.
Fluctuations are mainly produced by
a) continuously but randomly varying large loads such as:
1 ) resistance welding machines;
2) rolling mills;
3) large motors with varying loads;
4) arc furnaces;
5) arc welding plant;
b) single on/off switching of loads (e.g. motors);
c) step voltage changes (due to tap voltage regulators of transformers).
These industrially produced fluctuations can affect a large number of consumers. Suchequipment operates continuously or infrequently.The public supply network impedance haswide variations,consequently the transmission of the disturbances will be different for differentnetworks.
4Definitions
For the purpose of this part of lEC 61000, the following definitions and terms apply. They areapplicable only to the field of voltage fluctuations; not all of them areincluded inlEc 60050(161).
4.1
immunity
ability of a device,equipment or system to perform without degradation of performance in thepresence of an electromagnetic disturbance [IEV 161-01-20]
4.2
voltage fluctuations
series of voltage changes or a cyclic variation of the voltage envelope [IEV 161-08-05]
5Test levels
This test may apply to all equipment intended for connection to public networks,industrialnetworks and electricity plants that are likely to be sensitive to this type of disturbance.
lt can be assumed that step voltage changes are the most disturbing type of voltagefluctuations.
The equipment under test(EUT) is initially operated using a steady supply voltage and is thensubjected to repetitive step voltage changes according to figure 1a.
The initial voltage is set to
Un,Un -10 % Un,Un+ 10 % Un
NOTE u is the nominal voltage.
The magnitude of the voltage steps is chosen as follows:
Class 1: no test required.
Class 2: ⊗ U = 8 % U n for equipment intended for connection to public networks or other lightly disturbed networks. This test level is specified for class 2.
Class 3: ⊗ U = 1 2 % U n for equipment connected to heavily disturbed networks (i.e.industrial networks). This test level is specified for class 3.
Classes 1, 2 and 3 are defined in annex A.
Table 1 gives the test levels for the different initial voltages:
U n , U n – 10 % U n , U n + 10 % U
IEC 61000-4-14 pdf download – Electromagnetic compatibility (EMC) – Part 4-14: Testing and measurement techniques – Voltage fluctuation immunity test for equipment with input current not exceeding 16 A per phase
