EM TEST CNI 501, Руководство по эксплуатации

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EM TEST CNI 501 / CNI 503
Manual of operation V 3.32 11 / 41
3. 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, IEC 61000-4-12 and ANSI.
There are different coupling network models available:
Model Burst Surge IEC Surge ANSI Ringwave
CNI 503B X X X X
CNI 503A X X -- --
CNV 503 -- X -- --
CNE 503 X -- -- --
CNI 501 X X -- --
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.
3.1. Coupling modes
The test can be conducted with different coupling modes.
61000-4-5 Surge immunity requirements
- Line or lines to protective earth (unsymmetrical) e.g. L1-PE; L1+L2+L3+N-PE
- Line to Line (symmetrical) e.g. L1-L2 or L3-N
61000-4-4 Electrical fast transients
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
3.2. Coupling to Signal Lines
The coupling to I/O lines is generally realized with other
coupling networks than used for power supply lines. The
loading of the I/O lines with big 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 CNV 504 and the
CNV 508 for four respectively for eight wire systems. For
coupling the EFT transient to signal lines the capacitive
coupling clamp is used. The clamp can also be
connected and controlled via the CNI 503 networks but
normally shall be connected directly to the coaxial output
of the generator itself.
Figure 3.1: External device plug for Burst and Surge