Teseq NSG 3040, Руководство пользователя

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14.4 Magnetic field options
Magnetic fields at mains frequency
Mains frequency magnetic fields simulate the kind of stray fields that occur
around current carrying power supply lines.
NSG 3040 together with MFO 6501 or MFO 6502 current sources generates
these test conditions in accordance with the IEC 61000-4-8 standard by inducing
a current into a magnetic field loop. The magnetic field produced is proportional
to the current within the loop parameters. IEC 61000-4-8 specifies a clean sine
wave to be used (THD <8%). This is met thanks to the use of a synthetic signal
generator together with an audio current amplifier. Other advantage of this solu-
tion is that both 50 and 60 Hz fields can be generated by the same instrument.
Pulsed magnetic fields
Tests with pulsed magnetic fields simulate the type of field produced surge
pulses such as those occurring during lightning strokes on buildings and other
metallic structures such as free-standing masts, lightning conductors, earth
networks, etc.
NSG 3040 generates these test signals in accordance with the IEC 61000-4-9
standard by inducing a current (generated by the surge module CWM 3450) into
magnetic field loop in which the magnetic field produced in proportional to the
current within the loop parameters.
It is recommended for the user to stay away (at least
a few meters) from the loop antenna while magnetic
fields are generated. Also keep away magnetic field sen-
sitive devices and items such as credit cards – magnetic
key cards etc… which might be influencedby the field.