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DTI-NMSPU project on uncertainties of immunity measurements

In 2002 Schaffner EMC Systems and Elmac Services completed this project on behalf of the National Measurement System Programme. This programme is sponsored by the UK DTI to support industry through improving measurement capability. The electrical segment includes work devoted to EMC tests. The project reported here looks at the RF immunity tests of IEC/EN 61000-4-3 and IEC/EN 61000-4-6.

Areas covered by the project report include:

  • comparison of transducers for the IEC 61000-4-6 conducted RF immunity test;
  • assessment of the effects of cable layout and AE common mode impedance on the repeatability of the IEC 61000-4-6 conducted RF immunity test;
  • analysis of field uniformity data for over 40 anechoic chambers worldwide, to determine uncertainties from under-testing of RF immunity in such chambers;
  • assessment of the effects of cable layout and termination variations on the repeatability of the IEC 61000-4-3 radiated RF immunity test;
  • investigation of the non-linearity of response of typical op-amp and digital circuits to applied RF stress.

Available documents

The project deliverables are encapsulated in an 8-page Executive summary and Best Practice Guide, a 72-page Main report, and six Annexes. These can be freely downloaded as PDF files from this page. Anybody involved in the IEC/EN 61000-4-3 and -6 immunity tests should read this material.


Select the material and package you want from the diagram below or from the links to the right of it. Right-click and select "Save Link As" or "Save Target As" to save the downloaded file to disk.

Use WinZip or similar to unwrap the zipped files. The .pdf files are compatible with Acrobat 3.0 and above. Ensure you unzip and save all files to the same directory for the inter-document hyperlinks to work.

Executive summary and best practice guide
Size 42kb
Main report
Size 880kb
Main report, summary and best practice guide zipped together
Size 850kb
Annex A: conducted immunity circuit model
Size 357kb
Annex B: conducted immunity test setup
Size 240kb
Annex C: conducted immunity graph results
Size 1715kb
Annex D: details of chamber performance
Size 656kb
Annex E: radiated immunity test setup
Size 437kb
Annex F: circuit susceptibility investigation
Size 341kb
All annexes zipped together
Size 3692kb