IEC 61000-6-4-2018 pdf free.Electromagnetic compatibility (EMC) – Part 4-8:Testing and measurement techniques – Power frequency magnetic field immunity test.
This part of IEC 61000 relates to the immunity requirements of equipment,only underoperational conditions,to magnetic disturbances at power frequencies 50 Hz and 60 Hzrelated to:
– residential and commercial locations;
– industrial installations and power plants;
– medium voltage and high voltage sub-stations.
The applicability of this standard to equipment installed in different locations is determined bythe presence of the phenomenon，as specified in Clause 4.This standard does not considerdisturbances due to capacitive or inductive coupling in cables or other parts of the fieldinstallation.
Other lEC standards dealing with conducted disturbances cover these aspects.
The object of this standard is to establish a common and reproducible basis for evaluating theperformance of electrical and electronic equipment for household,commercial and industrialapplications when subjected to magnetic fields at power frequency (continuous and shortduration field).
2 Normative references
The following referenced documents are indispensable for the application of this document.For dated references, only the edition cited applies.For undated references, the latest editionof the referenced document (including any amendments) applies.
IEC 60050(161),International Electrotechnical Vocabulary (IEV) – Chapter 161: Electro-magnetic compatibility
3 Terms and definitions
For the purposes of this document the following terms and definitions apply to the restrictedfield of magnetic disturbances as well as the terms and definitions from lEC 60050(161)[ IEV].
current distortion factor ratio of the root-mean square value of the harmonics content of an alternating current to theroot-mean square value of the fundamental current.
4 General
The magnetic fields to which equipment is subjected may influence the reliable operation ofequipment and systems.
The following tests are intended to demonstrate the immunity of equipment when subjected topower frequency magnetic fields related to the specific location and installation condition ofthe equipment (e.g. proximity of equipment to the disturbance source).
The power frequency magnetic field is generated by power frequency current in conductorsor，more seldom，from other devices (e.g. leakage of transformers) in the proximity ofequipment.
As for the influence of nearby conductors, one should differentiate between:
the current under normal operating conditions，which produces a steady magnetic field,with a comparatively small magnitude;
the current under fault conditions which can produce comparatively high magnetic fieldsbut of short duration,until the protection devices operate (a few milliseconds with fuses,afew seconds for protection relays).
The test with a steady magnetic field may apply to all types of equipment intended for publicor industrial low voltage distribution networks or for electrical plants.
The test with a short duration magnetic field related to fault conditions,requires test levelsthat differ from those for steady-state conditions; the highest values apply mainly toequipment to be installed in exposed places of electrical plants.
The test field waveform is that of power frequency.
In many cases (household areas,sub-stations and power plant under normal conditions), themagnetic field produced by harmonics is negligible.IEC 61000-6-4 pdf download.