Piotr, - If the product is sold with a fitted fixed adapter, there is no problem, measure the AC-port.
- If the product has an exchangeable adapter (very popular in IT) then measure the AC-port. (here my original discussion started about exchanging them) - If the product is sold without adapter , do not measure anything in EN 55022, and measure the DC port in almost all other product standards in Europe. Some generic comments about EN 55022: Here CISPR clearly dropped another chance to make it a true IT EMC standard. The interest of the authors clearly was not EMC, but lowest possible cost for the manufacturer, within the EMC directive's constraints. There is also the Class A/Class B issue, that is different from all other emc standards in the way that it does not allocate Class A to industrial locations and class B to residential locations. Furthermore EN 55022 (CISPR22) should comply ASAP to the CISPR 16 defined test volumes instead of holding on the non conductive (read: wood) tables, that we know all are obsolete and create measurement errors already below 1 GHz. And they are not round, making rotating it cumbersome in small test rooms. But of course CISPR 22 advise us: "For measurement purposes, it may be possible to rotate the EUT. When this is not practicable the EUT remains in a fixed position, and measurements are made around the EUT." About saving costs..... Gert Gremmen Ce-test, qualified testing bv Gert Gremmen Ce-test, qualified testing bv Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens Piotr Galka Verzonden: maandag 8 juni 2009 14:57 Aan: EMC-PSTC; John Woodgate Onderwerp: Re: CISPR 22-2005: testing on interconnecting DC cables? John, From: "John Woodgate" <j...@jmwa.demon.co.uk> > > Formally, you are 'gold-plating' the standard - extending beyond its > internationally-agreed requirements. You should make a proposal to amend > the standard in accordance with your view, so that it can be tested in the > proper forum. > How I should understand the current standards (EN55022, EN55024) ? How the conducted disturbance at mains terminals of 12V DC powered device should be measured: 1. At its 12V DC input ? 2. At mains input of "standard" 12V (buffered) supply (the same problem as with "standard" PC) ? 3. Not measured at all as device has not mains terminals ? The same question regarding immunity: At DC input or at AC input of "standard" 12V buffered supply. The same "standard" supply used several times can fail Surge sometimes - what then. Should I use each time new "standard" supply and then WEEE it as used equipment ? When I was speaking (my first attempt to EMC) with one accredited lab (in 2002) they said I have to come with "standard" supply because they have no supply to destroy it for my measurements. When in 2004/2005 I've done some measurements (one firm's lab) they just measured at DC input (they also produce a lot of 12V powered devices and measure them that way). Best regards Piotr Galka - 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.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.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...@socal.rr.com> 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.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.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...@socal.rr.com> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
