I have seen significant interference on magnetic pickups in a recording studio from a DC tram. The problem is the significant harmonics from the 12 pulse rectifiers which fall in the audio band. Is that what you are using for the calculation?
Best Regards John John McAuley www.cei.ie john.mcau...@cei.ie ***************************************************************** DISCLAIMER: The information contained in this e-mail may be confidential and is intended solely for the use of the named addressee. Access, copying or re-use of the e-mail or any information contained therein by any other person is not authorised. If you are not the intended recipient please notify us immediately by returning the e-mail to the originator -----Original Message----- From: John Woodgate [mailto:j...@jmwa.demon.co.uk] Sent: 24 January 2014 16:29 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Audio Frequency Induction Loop In message <beda313b3e2b304ca6a08001bd61c9c01a257...@ukmb01.mottmac.group.int>, dated Fri, 24 Jan 2014, "McCallum, Andy" <andy.mccal...@mottmac.com> writes: >Anyone aware of any interference from Trams (750V DC Overhead Catenary >Systems, max current 1000A) on AFIL systems (EN 60118-4:2006). From my >very basic calculation you need a significant separation distance (in >excess of 25m). Any previous studies or examples would be most helpful. I don't have any studies or examples, but I'm heavily involved with that standard; I'm actually editing the next edition today! Of course, the system doesn't pass DC and very low and high frequencies, so it's a question of transients, from about 20 ms down to perhaps 100 μs. If you care to tell me how you calculated 25 m, I will compare it with my calculations. Meanwhile, I'll ask around in the AFILS community. Any reports submitted here might well contribute to the next but one edition of IEC 60118-4 or a planned Technical Report covering all aspects of AFILS - purchase, design, installation, maintenance and 'care and feeding'. -- OOO - Own Opinions Only. With best wishes. See www.jmwa.demon.co.uk Nondum ex silvis sumus 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 <emc-p...@ieee.org> 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 <emcp...@radiusnorth.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com> - ---------------------------------------------------------------- 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 <emc-p...@ieee.org> 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 <emcp...@radiusnorth.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
