In message <c2b13257.58e9f%[email protected]>, dated Wed, 4 Jul 2007, Ken Javor <[email protected]> writes:
>I have no idea what is being requested here, but from a technical >standpoint it is insufficient to specify a magnetic field alone; But this is exactly what EMC immunity standards specify (either H in A/m or B in tesla). Since dB/dt is strictly proportional to d(phi)/dt in space or air, there doesn't seem to be any need to appeal to phi directly > it is important to specify over what area (magnetic flux) the magnetic >field intensity must be induced, since coupling from magnetic fields is >proportional to the time rate of change of magnetic flux (Faraday) not >the field intensity alone. The implication, surely, is that the product is subjected to a homogenous field of an area at least as large as the plane projection of the product in the direction of the field. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk There are benefits from being irrational - just ask the square root of 2. John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - 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 ______________________________________________________________________
