This is a typical standards clause included in a standard by non-emc "experts".
What is a metal enclosure, and when is it not enclosure ? Metalized plastic: is not metal but might be as good Painted metal: complies but may have substantial potential difference between parts If heavy interference exists, 4 braid connection points are not enough, and inferior braided coax and signal cables is all over the market. This is an example of economic drive "fast cheap & pragmatic testing" and this exemption clause is a recipe for problems in the field. I remember a customer of mine building PA systems for a church application ( = 55103-2) Final testing was ok, and the system worked like a charm. The first Sunday in real use, the vicar got an unexpected reply on its questions to the mighty when a local 27 MHz radio amateur switched on its transmitter and "preached" : "blue angel calling red devil ".... Gert Gremmen ce-test qualified testing bv -----Oorspronkelijk bericht----- Van: John Woodgate [mailto:[email protected]] Verzonden: vrijdag 11 september 2015 16:48 Aan: [email protected] Onderwerp: Re: [PSES] RF Common Mode Immunity Test Question In message <[email protected]>, dated Fri, 11 Sep 2015, Robert Dunkerley <[email protected]> writes: >Would this not imply that nearly all types of signal cables (most are >screened this way?) would be exempt from this test, or is my >understanding totally wrong? (probably the case!) Not all products have a metal case. Not all ports meet the definition of 'screened port'. Not all cables have braided screens/shields. -- OOO - Own Opinions Only. With best wishes. See www.jmwa.demon.co.uk When I turn my back on the sun, it's to look for a rainbow John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]> - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
