IEC 61000-4-9:2001 pdf download

IEC 61000-4-9:2001 pdf download.Electromagnetic compatibility (EMC) –
Part 4-9: Testing and measurement techniques一 Pulse magnetic field immunity test.
3 General
The magnetic fields to which equipment is subjected may influence the reliable operation of
equipment and systems.
The following tests are intended to demonstrate the immunity of equipment when subjected to
impulse magnetic fields related to the specific location and installation condition of the
equipment (e.g. proximity of equipment to the disturbance source).
Pulse magnetic fields are generated by lightning strokes on buildings and other metal
structures including aerial masts, earth conductors and earth networks and by initial faults
transients in L.V.. M.V. and H.V. electrical systems.
In HV. sub-stations, a pulse magnetic field may also be generated by the switching of H.V.
bus-bars and lines by circuit breakers.
The test is mainly applicable to electronic equipment to be installed in electrical plants as well
as in telecontrol centres. It is not relevant for distribution network equlpment.
Possible other applications may be considered by the product comittees.
The test field waveform is that of the standard current pulse, waveform 6,4/16 μs.
NOTE The waveform 6.4/16 μs according to IEC 60469-1 corresponds to the 8/20 μs of IEC 60060-2 .
4 Definitions
The following definitions and terms are used in this standard and apply to the restricted field
of magnetic disturbances; not all of them are included in IEC 60050( 161) [IEV].
4.1
EUT
equipment under test
4.2
induction coil
conductor loop of defined shape and dimensions. in which flows a current, generating a
magnetic field of defined constancy in its plane and in the enclosed volume
4.3
induction coil factor
ratio between the magnetic field strength generated by an induction coil of given dimensions
and the corresponding current value; the field is that measured at the centre of the coil plane,
without the EUT
4.4
immersion method
method of aplication of the magnetic field to the EUT, which is placed in the centre of an
induction coil (figure 1)
proximity method
method of application of the magnetic field to the EUT, where a small induction coll is moved
along the side of the EUT in order to detect particularly sensitive areas
6.1
Test generator
The generator, with the output waveform corresponding to the test magnetic field, shall be
able to deliver the required current in the induction coils specified in 6.2.
The generator power capbility shall therefore be dimensioned by taking into account the coil
impedance; the inductance may range from 2,5 μH for the 1 m standard coil, to several μH
(e.g. 6 μH) for a rectangular induction coll(1 mx2,6 m, see 6.2).
The specifications of the generator are:
”current capability, determined by the maximum selected test level and induction coil factor
(see 6.2.2 and annex A), ranging from 0,87 m-1 (1 m standard coll for testing table-top or
small equipment) to 0,66 m-1 (rectangular induction coil, 1 m x 2,6 m, for testing floor-
standing or large equipment);
operability in short-circuit condition;
low output terminal connected to the earth terminal (for connection to the safety earth of
the laboratory):
precautions to prevent the emission of large disturbances that may be injected in the
power supply network or may infuence the test results.
The characteristics and performances of the current source or test generator for the field
considered in this standard are given in 6.1.1.
6.1.1
Characteristics and performances of the test generator
The test generator is a non-repetitive (single shot) pulse current generator with characteristics as follows:
A standard current pulse generator. e.g. the surge hybrid generator (waveform 1,2/50 –
6.4/16 μs) may be used.
NOTE The output current range for the standard col is from 120 Ato 1 200 A peak.
The waveform of the output current is given in figure 2.
The schematic circuit of the generator is given in figure 3.
6.1.2
Verification of the characteristics of the test generator
In order to compare the results for dfferent test generators, the essential characteristics of
the output current parameters shall be verified.
The output current shall be verified with the generator connected to the standard induction
coil specified in 6.2.1 a); the connection shall be realized by twisted conductors or coaxial
cable of up to 3 m length and suitable cross-section.