There are some significant difference in the history of emissions and immunity between the United Sates and Europe.
First, the power systems are different. The U.S. has more separation between residential, commercial and industrial customers. There tend to be very few customers connected to a single distribution transformer. This tends to limit problems from conducted emissions. It is unlikely that conducted noise from an industrial facility would affect residential customers. There is also significant geographic separation between industrial and residential customers. The American preference for single-family homes tends to separate a significant portion of the population from each other. Although the United States has a few areas with high population density such as New York, Chicago or Boston, the portion of the population living in a dense urban area may not be as high as in Germany. Further, it is more common in Europe to have a mix of commercial and residential customers on the same power system. You may even have some light industrial users on that power system. The chances of interference have historically been higher. The proliferation of wireless devices and electronics may change the American view of the necessity for immunity testing. But there may also be another factor at work. Many manufacturers of devices that could have immunity problems design those devices for world wide use. It is likely that the version sold in the United States has either been tested for immunity for sale in Europe, or it shares a largely common platform with a European version. As far as I know, there have been few public calls for improved immunity requirements in the United States. Ted Eckert APC-MGE http://www.apc.com/ The items contained in this e-mail reflect the personal opinions of the writer and are only provided for the assistance of the reader. The writer is not speaking in an official capacity for APC-MGE or Schneider Electric. The speaker does not represent APC-MGE's or Schneider Electric's official position on any matter. John Woodgate <jmw@jmwa.demon.c o.uk> To Sent by: emc-p...@ieee.org emc-p...@ieee.org cc Subject 05/02/2008 07:38 Re: FCC Immunity Requirements AM In message <2a93eb060805020512se98e1d4x8d63d1a2a755f...@mail.gmail.com>, dated Fri, 2 May 2008, Grace Lin <graceli...@gmail.com> writes: >Last March, I had an oppotunity to sit with an EU policy maker for a >dinner. I expressed FCC's position about immunity requriement. He >agreed with it. However, it maybe not easy to withdraw the immunity >requriements from the EMC Directive. For manufacturers, it is not a >big deal to meet both emission and immunity requriements (since EU >requirements are self declaration). However, if other countries follow >up and post in-country testing requriements, this would be a big issue >for manufactrurers. You were told only part of the story. From the point of view of the spectrum management authorities, the PRIMARY purpose of EMC control is to reduce to an acceptable minimum the number of complaints of interference. This is because they are costly to investigate. I don't know what the history of EMC is in USA, but in Europe in the 60s and 70s there were many problems caused by lack of immunity, not excessive emissions. This was particularly evident in Germany, where emission control was intense. So it was, and still is, very much in the interests of both responsible manufacturers and the spectrum management authorities to have control of both emissions AND immunity embodied in the EMC Directive. Since this is unlikely to be a peculiarly European phenomenon, I think we can expect immunity requirements to be introduced where they do not already exist. However, mandatory in-country testing is a barrier to trade and must be opposed, in favour of mutual recognition agreements. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk Murphy's Law has now been officially re-named The Certainty Principle 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 emc-p...@ieee.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 emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com 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 emc-p...@ieee.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 emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
