Teseq NSG 3040, Руководство пользователя

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NSG 3040 EMC test system
nominal level for a relatively short time, e.g. for a few cycles, whereas an inter-
rupt means that the voltage falls to zero for a similar period.
3.4 Magnetic fields with mains frequency
Mains frequency magnetic field tests, or POWERM tests, involve the simulation
of the magnetic fields typically generated by the current flow in power supply
cables as specified in IEC/EN 61000-4-8. Such magnetic fields can affect the
operation of items of equipment that are sensitive to them. The NSG 3040
performs this test by causing a heavy current to flow in a magnetic field coil
such that the current and frequency produce a proportional field within the
coil parameters.
The magnetic field coils, available as accessories, are connected to the mag-
netic field option (MFO) which, in turn, is connected to the system.
3.5 Pulsed magnetic fields
Tests with pulsed magnetic fields, or PULSEM tests, simulate the type of inter-
ference produced by surge pulses as a result of lightning strikes to buildings
and other metallic structures such as freestanding masts, ground conductors,
grounding networks, etc. as specified in IEC/EN 61000-4-9. Magnetic fields of
this type can upset the operation of installations that find themselves within
such fields. The NSG 3040 performs this test by causing a heavy current to flow
in a magnetic field coil such that the amplitude of the pulse current produces
a proportional field within the coil parameters.
The magnetic field coils, available as accessories, are connected to the surge
pulse output socket via an INA 752 pulse shaping network.
3.6 Slow Damped Oscillatory Wave (NSG 3040-SOW only)
The damped oscillatory wave phenomena are divided into two parts. The first
part is referred to as the slow damped oscillatory wave (SOW) and includes
oscillation frequencies of 100 kHz and 1 MHz. The second part is referred to as
the fast damped oscillatory wave (FOW), and it includes oscillation frequencies
3 MHz, 10 MHz and 30 MHz.
The slow damped oscillatory wave immunity test simulates switching of dis-
connectors in HV/MV open-air substations, and is particularly related to the