Hi All, I'd just like to point out here that the EN does not give any criteria for the dielectric withstand nature of the spacer. So, while we can argue best practice, if a lab meets the thickness, all is permissible.
I also disagree with Doug's statement on cables. You must test with whats supplied by the manufacturer, or with ones that he states you must use. Why, well because cables can make a huge difference in performance. I would call messing with cables like this part substitution and fraud. I also disagree about using new cables. The reason for this is that cables will degrade with some flexing and you should be assuring a product meets the EMC requirements for it's design lifetime, not on a good day in a lab, with the wind behind it and rubber boots on. Just trying to keep the common sense hat on compliance testing Cheers, Derek Walton. -----Original Message----- From: Doug Smith <[email protected]> To: Sundstrom, Michael <[email protected]> Cc: Bryce Stammerjohan <[email protected]>; EMC-PSTC <[email protected]> Sent: Mon, Jul 25, 2011 8:59 pm Subject: Re: [PSES] ESD Spacer If the poster board is 0.5 mm thick as required, you may be failing equipment that might otherwise pass, which I have seen happen. A spark through the poster board will likely be worse than the one you supply from the ESD simulator in terms of peak current and di/dt. In any case, unless the poster board in 0.5mm thick and you have confirmed there is no spark through, than you cannot say you have tested to IEC 61000-4-2! Maybe OK for a pretest but not for CE marking. It's hardly worth it to save a few cents on test materials (the insulating layer we are talking about, USB cables, Ethernet cables, and many other things) and waste thousands of dollars in the end. I see this happen a dozen times per year. I also recommend using new, high quality cables for any performance test. This is especially important for USB and Ethernet cables. Doug On 7/25/11 10:32 AM, Sundstrom, Michael wrote: Guys, I just use poster board, I get 20 sheets at a local office supple house for $5-$6 ? Am I missing something? Do you need plastic sheets? Michael Sundstrom OHD / TREQ Dallas Electronic Lab Analyst, EMC Lead 2170 French Settlement Rd, Suite B Dallas, Texas 75212 (214) 579 6312 (940) 390 3644c KB5UKT Albert Einstein once said, "The definition of insanity is doing the same thing over and over again and expecting different results". From: Bryce Stammerjohan [mailto:[email protected]] - ---------------------------------------------------------------- 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 <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://product-compliance.oc.ieee.org/ 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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
