Surge, Telecom, ring wave CDNs for interconnection and control lines
Conducted immunity test specified in the IEC 61000-4-X series are applied to a broad series of ports/lines. The major categories in standards like IEC 61000-4-5 and IEC 61000-4-12 are: AC/DC power lines and interconnection lines.
How to choose a CDN for interconnection lines?
The major differences when applying surge, telecom surge (10/700 μs voltage waveform as per Annex A from IEC 61000-4-5) and ring wave refer to test levels, source impedance and coupling mode (differential and/or common mode).
The interconnection lines are themselves subdivided categories in function of two parameters: symmetrical/unsymmetrical and shielded/unshielded. Hence four categories of interconnection lines result, as described in the table below.
Surge 1.2/50 μs and ring wave are to be applied in differential mode and common mode on unsymmetrical unshielded lines. There are no requirements to apply 10/700 μs surge on unsymmetrical unshielded lines.
Surge, telecom surge and ring wave disturbances are to be applied only in common mode to symmetrical unshielded lines.
Finally, shielded lines do not require a CDN, as the impulses coming from generator output are applied directly on the shield.
The CDNs provided by EMC PARTNER for interconnection lines (listed in the table above) are designed to cover a broad range of applications. CDN-UTP8 ED3 for example, can be used for both high speed symmetrical (1 Gbps) and unsymmetrical interconnection lines, apply up to 6 kV surge and ring wave disturbances in both differential mode and common mode. Technical specifications can be found in the technical specifications.
|Electromagnetic compatibility (EMC) - Part 4-4: Testing and measurement techniques|
|Electromagnetic compatibility (EMC) - Part 4-5: Testing and measurement techniques - Surge immunity test|
|Resistibility of telecommunication equipment installed in a telecommunication centre to overvoltages and overcurrents|
|Resistibility of telecommunication equipment installed in customer premises to overvoltages and overcurrents|
|Resistibility tests for telecommunication equipment exposed to overvoltages and overcurrents - Basic Recommendation|