Regan, I'm not sure I understand your question correctly, but I will try to provide an answer. ANSI C63.4 is used when testing for FCC part 15 subpart B compliance for unintentional radiators. When testing a table-top system, the collocated equipment should be spaced at 10cm, unless this is not typical of normal operation. If so, then the EUT and its accessories/peripheral devices should be placed as they would be in typical applications. It is important to read the text of the ANSI standard, as it goes into great detail on how to set up and select accessories for testing. The drawings are for general reference only and the text always takes precedence. As for EN/CISPR standards, they mostly accept similar setup conditions to ANSI C63.4, but you will have to verify the specific requirements in each standard. The <20cm you refer to was at one time unofficially (FCC) considered the distance for collocation of transmitter antennas, but this is no longer the case. The FCC considers that two transmitters/antennas are collocated if they are in the same product / enclosure. I hope this helps.
Bill From: Regan Arndt [mailto:re...@empowermicro.com] Sent: Wednesday, March 08, 2017 1:50 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] EMC co-location distance question Greetings members, Can anyone shed any light on what ANSI defines as the max distance/limit of a 'co-located' piece of ancillary equipment or other support equipment (on the table) to the main EUT being tested for FCC Part 15 class B for 'unintentional radiators'. I seem to recall 20 cm but I think this was referring to 'intentional' radiators. Is there a similar requirement in the EMC directive and/or EN/CISPR standards? Or is this really dictated on your recommended set-up? Shall that device be removed from the test bed if typical installation indicates that it will be greater than 20cm from the main EUT? I believe that the set-up in ANSI only showed the PC, printer, mouse, keyboard & monitor but that's it. There are so many other/different electronic devices that connect to a laptop/PC/other, etc. (i.e. smart phone) these days, it is not viable for anyone to test all devices/configurations. I understand that one must use good judgment and exercise due diligence but there must be a limit. Agree? Some of these electronic devices state compliance to Class B, it may still have interference with another closely co-located device because they did not test it fully to the myriad of other electronic devices out there that it could be connected to. There is no guarantee per se. Can anyone comment? Thanks in advance. Regan - ---------------------------------------------------------------- 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<mailto:emc-p...@ieee.org>> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe)<http://www.ieee-pses.org/list.html> List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <sdoug...@ieee.org<mailto:sdoug...@ieee.org>> Mike Cantwell <mcantw...@ieee.org<mailto:mcantw...@ieee.org>> For policy questions, send mail to: Jim Bacher <j.bac...@ieee.org<mailto:j.bac...@ieee.org>> David Heald <dhe...@gmail.com<mailto:dhe...@gmail.com>> CONFIDENTIALITY NOTICE: This message is intended only for the use of the person or organization to which it is addressed or was intended to be addressed, and may contain information that is privileged, confidential and exempt from disclosure under applicable law. If the reader of this message is not the intended recipient, or responsible for delivering the message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this communication in error, please notify the sender immediately by email and delete the original message immediately . The sender, its subsidiaries and affiliates, do not accept liability for any errors, omissions, corruption or virus in the contents of this message or any attachments that arise as a result of e-mail transmission. Thank you. - ---------------------------------------------------------------- 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.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <sdoug...@ieee.org> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
