1000-4-6 models the effects of an electromagnetic field coupling to a cable at frequencies where it is difficult or impossible to adequately illuminate the cable-under-test with an actual electromagnetic field, i.e., at frequencies lower than 80 MHz per 1000-4-3.
> From: "Oliver Betz" <[email protected]> > Date: Mon, 26 Feb 2007 17:34:05 +0100 > To: [email protected] > Subject: Re: Conducted immunity lower frequency > > Ken Javor wrote: > >> I disagree with what I perceive is being stated here - that if any portion >> of a system has a connection to a long conductor, then all system-attached >> cables must be tested down to 150 kHz. > > I didn't write this. > >> The purpose of the Annex B wording is to allow for basic physics to be >> applied to the limit - short cables are inefficient pick-up at low > > "pick up" _what_ - field? > > I'm writing about galvanically coupled disturbances. > >> frequencies. It is the length of the individual cable-under-test which >> should drive the low-frequency cut-off limit. > > What about this: > > ...---long------[AE]-short-[EUT] > > > Also very popular: > > [SMPS]--short--[EUT] > | | > '--GND PLANE---' > > The SMPS itself generates strong common mode noise. > > Let it be battery powered => no long cables anywhere. > > > Strong commond mode voltages are widespread in industrial > installations - especially at very low frequencies. > > > Antitheft equipment can induce several volts in really small (1m) > loops. Well - that's usually even below 150kHz... > > Oliver > -- > Oliver Betz, Muenchen > > - > ---------------------------------------------------------------- > This message is from the IEEE Product Safety Engineering Society > emc-pstc discussion list. Website: http://www.ieee-pses.org/ > > To post a message to the list, send your e-mail to [email protected] > > 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] > > All emc-pstc postings are archived and searchable on the web at: > > http://www.ieeecommunities.org/emc-pstc > - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] 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] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________
