General; Coupling Modes; Coupling To Signal Lines - EM TEST coupling NX5 bs-3-480-16 Manual

EM TEST
6.

General

The coupling network has to couple the transients well defined to the lines of a power supply system. The coupling is
realized by discrete coupling capacitors, having a sufficient voltage capability and bandwidth. The specification is
given in IEC 61000-4-4, IEC 61000-4-5.
The coupling/decoupling network is divided in two parts:
- The decoupling and filtering unit
- The coupling unit
The decoupling unit has to
To decouple the low impedance power mains supply from the test setup.
-
protect other equipment which is connected to the power mains supply
-
But which is not part of the test set-up.
The coupling network superimposes the transients to the lines of a power supply system, AC as well as DC supply.
6.1.

Coupling modes

The test can be conducted with different coupling modes.
61000-4-5 Surge immunity requirements
- Line or lines to protective earth (unsymmetrical)
- Line to Line (symmetrical)
61000-4-4 Electrical fast transients
Coupling mode line, or lines to reference ground. All combinations are possible. The protective earth (PE) is
regarded as equal to all other lines and therefore is tested as all other lines
6.2.

Coupling to Signal Lines

The coupling to I/O lines is realized with other coupling
networks than used for power supply lines. The loading of
the I/O lines with large coupling capacitors is mostly not
possible. The data transmission may be disturbed
For coupling to I/O lines special couplers acc. to IEC
61000-4-5 are available, such as the DCD series and
previous CNV 504 and the CNV 508 family for eight wire
systems.
For coupling the Burst transient to signal lines, a
capacitive coupling clamp is used. The clamp is
connected and controlled via the coupling NX. Normally it
is connected directly to the coaxial output of the generator
itself.
gure 6.1: External device plug for Burst and Surge
Fi
Manual of operation
e.g. L1-PE; L1+L2+L3+N-PE
e.g. L1-L2 or L3-N
V 1.03
coupling NX
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