Teseq NSG 3040, Руководство пользователя

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NSG 3040 EMC test system
Coupling: EC/external/manual
Pulse repetition: 10* .... 600 s (in 1 sec steps)
1 .... 10 min.
Test duration: 1 to 9999 pulses
Continuous
* Repetition rate depends on voltage:
200 to 4400 V = 10 s repetition time
4401 to 6600 V = 20 s repetition time
8.5 Dips, interrupts and variations
Dips, interrupts and variatons tests are in line with the specifications of IEC
61000-4-11.
The EUT suppy voltage (Input La), gets switched off shortly via a semiconductor
switch, in order to generate short supply interrupts.
A second switch is available in the generator, with a second input channel (Input
Lb) where a variable supply can be connected. This second switch works in
opposition with the first one, so always one of the 2 switches is closed when the
other one is open. Generally a step transformer or a variac is used as second
supply, powered by the same supply than Input La, in order to have phase
synchronisation of the 2 input sources. This setup allows “dips”, which are short
voltage variations from one supply voltage level (provided through generator
Input La), to another voltage level (provided through generator Input Lb).
EUTs with “universal” supply voltage ranges (ex: 85 to 245 VAC) need to be
tested for both extremes of supply. For this application Teseq offers a double
variac VAR 3005-D16, which allows to provide the variable voltage required for
EUT powering, as well as the variable voltage of the dip, this in one box, and
powered from a single mains.
The use of a motorised variac as VAR 3005 also allows running variation tests,
which are slower changes in EUT supply voltage.
Using DC supplies instead of AC supplies allows to test DC powered EUTs on a
similar way. This is in line with the specifications of IEC 61000-4-29