Ops – should be cheapo depo, not cheapo dopeJ
From: Dward [mailto:dw...@atcb.com] Sent: Saturday, June 19, 2010 2:55 PM To: 'k...@earthlink.net'; 'EMC-PSTC@LISTSERV.IEEE.ORG' Subject: RE: [PSES] EMC Performance Changing With Age Of Product Seems to be the old scenario of: 1 – know exactly what your device does, test it till it breaks, find out just what it can do and can’t do – expensive – but you end up with a superior product far above the average – a rock solid device. 2 – assume your product is OK, but test just a little more than the standards –costly but less expensive than 1, and you wind up with a product that generally works in most instances and has not too bad of a return rate – a pretty good device. 3 – do only exactly what the standard says, no more no less - inexpensive compared to 1 and 2 but prone to wander and works most of the time as long as no extremes or no hard use exists – a mid end ‘Best Buy’ product 4 – only do the absolute minimum in the standard and if you can get away with it, lean towards no test rather than test – a mediocre at best product with nothing special, super deal at the stores (probably because the store just want to get rid of them) 5 – find some way to get out of reasonable testing, possibly some fudge factoring involved in the way testing is explained – el cheapo dope deal almost guaranteed to break the second warranties run out. But that is just my way of looking at it.:) From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Cortland Richmond Sent: Saturday, June 19, 2010 1:05 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] EMC Performance Changing With Age Of Product Tuppence from my corner... Once upon at time at Wang Labs, we noticed emissions performance improved after transportation vibe tests. I attributed this to having scraped surface oxidation off mating surfaces of shielding chassis'. A reasonable inference could be made that over time oxides might build and degrade shielding. this could (and IMO should) inform those with input to mechanical design. Cortland Richmond KA5S ----- Original Message ----- From: Derek Walton <mailto:lfresea...@aol.com> To: Mark Schmidt <mailto:mschm...@xrite.com> Cc: ralph.mcdiar...@ca.schneider-electric.com; EMC-PSTC@LISTSERV.IEEE.ORG Sent: 6/15/2010 4:55:22 PM Subject: Re: [PSES] EMC Performance Changing With Age Of Product Hi All, just throwing in my 10 cents from when I worked for an automotive component manufacturer. Contary to what a so called expert has written recently, we were required to test the stuffing out of out parts. Specifically: We tested 5 parts from a sampled lot of 60. Before we began the EMI testing, our 5 parts were sent through some of the environmental tests to simulate product lifetime. The goal was to age the parts.... The very first test we did was ESD, to wicked levels including the pins. This was to simulate being installed in dry climates with no protective measures. The after sales market was seen as the most severe requirements. Some of the ceramic caps we initially used showed ESD induced cracks and electromigration. Our tests included 200 /m testing up to 18 GHz. While this may not be truly representative of lifetime testing, it was recognizing that it was important. Cheers, Dere! k Walton L F Research - 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>
