I read in !emc-pstc that Enci <e...@cinepower.com> wrote (in <3.0.6.32.2 0011206095941.00970...@mail.cinepower.com>) about 'EMC. 10db over limit = unsafe?', on Thu, 6 Dec 2001: > >Hi Group, > >If I have a product, a finished apparatus, that passes all LVD or safety >tests, i.e. earth leakage, insulation, etc., is that product "unsafe" if it >is 10db over the conducted emissions limits for EMC?
No. > >Article 4 and Annex III of the EMC directive do not refer to safety, only >to the concept that equipment will not hinder the use of other equipment >and immunity. > >Where does this 80/80 rule now fit in that was discussed recently - >specifically if authorities acknowledge the fact that there may be >equipment out there that exceeds the EMC emissions limits for their product >type? > The rule is to allow for variations in volume production. Such variations are normally small (a few dB only) and would require full testing of every unit, at huge cost, to determine the variation with acceptably low uncertainty. It is by no means a loophole that allows you to ship product that is 10 dB over the limit. >Also in Annex III, it states: > >"The information required to enable use in accordance with the intended >purpose of the apparatus must be contained in the instructions accompanying >the apparatus." > >Does this then imply that the manual must state that suitable measures must >be taken to ensure compliance? e.g. additional filter? > Under the present Directive you cannot ship a product that needs a filter UNLESS you ship the filter with it, and the manual must explain that it is essential to use it, and give instructions on how to install it. The draft new Directive changes this a bit, but the new Directive is long-delayed and may never appear. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: pstc_ad...@garretson.org Dave Heald davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
