It seems to me that if a manufacturer of such a wall wart wanted to immunity qualify his unit alone it would be a worst case to put a resistive load on it and monitor output power quality not to change during application of transient (or not exceed some TBD limit).
on 10/26/04 10:27 PM, Wan Juang Foo at [email protected] wrote: > Hi PSTC Forum, > Recently I reveived an enquiry regarding testing wall warts (AC/DC > adaptors) to IEC 61000-4-4 and -5 without their 'wards' ( portable device > like Cellphone, Laptops, PDA, MP3 player etc..). I note that these wall > warts are bundeled and sold together even though these are ususally general > purpose and can be bought 'off the shelf' in a 'supermarket'. > > What is our take on this. > > Tim Foo > > > ------------------------my reply ----------------------------- > > Wei Chong, > Looks like the question concerns wall warts (AC/DC adaptors). On the > surface I would say that since the wall warts are bundeled together with > the product and sold as 'one set', they should be tested together. As far > as EMC is concererned, if these wall warts are tested as a standalone unit, > it is unlikely to get representative results because of the dynamic nature > of the load the wall warts would face in the field. There again, if it is > strictly compliance testing... speaking as a product designer, we should > onlt test to pass the item in question. > > Note that CE+CE is not Equal to CE > > <snip> > > With your permission I ... forward your question to the IEEE PSTC (Product > Safety Technical Com.) Forum and you will no doublt get a lot more from the > 'group'. Otherwise you can join the miss mash if you don't mind the loads > of responses from out-of-office replies and what-have-you every time one > send in a posting into the forum. Details are below... :-) sincerely > > Tim Foo > <usual PSTC footer ...snip> > ---------------------------originating email------------------------------- > > > Dear Mr Foo, > > Recently I was looking thru the IEC 61000 series document (IEC 61000-4-5 is > one of those, see enclosed). It actually spell out the requirement needed > to withstand for AC operated electrical product, under a "noisy" AC supply > environment. After further investigation on the requirement, it seems like > for those portable device like Cellphone, Laptops, PDA, MP3 player > etc..need NOT undergo these requirements. Infact only the charger is > required to test the IEC1000 requirement and not the portables. > > I'm just curious why the requirement did not insist on testing the product > as a whole, ie testing the IEC 61000-4-5 together with the charger & the > portable, since many a times people do use the portable when it's > charging... > > Just in case you are not the right person to answer, would appreciate you > could help to forward my queries to anybody whom you know of that can help. > > Thank you. > > Best Regards > WeiChong > > ---------------------------------------------------------------- > 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/listserv/request/user-guide.html > > List rules: http://www.ieee-pses.org/listrules.html > > For help, send mail to the list administrators: > > Ron Pickard: [email protected] > Scott Douglas [email protected] > > For policy questions, send mail to: > > Richard Nute: [email protected] > Jim Bacher: [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/listserv/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Ron Pickard: [email protected] Scott Douglas [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
