In message <09b7dbfe70a9e24bbb21689dad3a06141797e...@zcarhxm1.corp.nortel.com>, dated Thu, 10 Sep 2009, RICHARD JONES <[email protected]> writes:
>I just wanted to add my two pence worth to the debate: > >EN55022 defines a telecom port as something that is "intended to >connect to wider dispersed systems" and lists common types such as PSTN >ISDN xDSL & Ethernet. > >it also states "via such means as direct connection to multi user >telecommunication networks" > >I'm surprised that Australia interpreted this into cable length, > >Ethernet is listed so a LAN cable would be tested The 'brand name' of the signalling protocol doesn't determine the emissions (or the immunity). The length of the cable does. So Australia is actually using a proper technical criterion, whereas the wording in some standards is culpably loose and misleading. Lists of examples are particularly pernicious, and I wish IEC/CISPR would ban them. However, the technical criterion must be applied to what COULD be connected, subject to any restriction imposed by the manufacturer, 'e.g. labelling a port 'Intended ONLY for connection to Unit B or C, with a cable not more than 3 m long.' -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk Things can always get better. But that's not the only option. 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.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html 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]>
