"- the lack of any widespread ESD failure phenomena, even with world-wide permeation of electronics into everyday life, indicates that the standards groups are doing a great service for the public, although somewhat anonymously."
When I was a member of the AE-2 Committee for Lightning Protection of Aircraft, there was some discussion about the balance between making the tests sufficiently rigourous, and keeping them economically feasible. My question "How do we know that the specified test levels are correct?" drew the response "We don't have aircraft falling out of the sky." I've seen some horrific damage inflicted on aircraft that continued to fly, and were able to land safely. Standards committees do good work. Regards, David Raynes Senior EMC Technologist National Technical Systems Inc. 5151 - 47th Street N.E. Calgary, Alberta Canada T3J 3R2 1-403-568-6605 x227 Fax: 1-403-568-6970 [email protected] From: [email protected] [mailto:[email protected]] On Behalf Of Conway, Patrick R (Houston) Sent: Tuesday, April 01, 2008 15:28 To: Cortland Richmond; Pettit,Ghery; Derek Walton Cc: Garnier,David S (GE Healthcare); emc-pstc Subject: RE: Looking for Barometric pressure meter Another interesting observation... Perhaps the lack of data showing correlation between a) atmospheric pressure at the test lab and b) widespread ESD upset in the field is an indicator that the test method and test levels (including lack of altitude restrictions) are sufficient to protect the consumer/user/public? - the lack of any widespread ESD failure phenomena, even with world-wide permeation of electronics into everyday life, indicates that the standards groups are doing a great service for the public, although somewhat anonymously. Best Regards, Patrick. [email protected] From: [email protected] [mailto:[email protected]] On Behalf Of Cortland Richmond Sent: Tuesday, April 01, 2008 3:10 PM To: Pettit,Ghery; Derek Walton Cc: [email protected]; Garnier,David S (GE Healthcare); emc-pstc Subject: RE: Looking for Barometric pressure meter I see the CCL OATS is in Wanship, UT, at about 6854 feet, and their HQ is in ZIP Code 84119, which Wunderland.com says is at 4380 feet. Cheyenne, Wyoming is at 6025 feet. Any test labs there? I suppose one might pressurize it... Cortland KA5S/6 >From: "Pettit, Ghery" <[email protected]> >Sent: Apr 1, 2008 8:34 AM >To: Derek Walton <[email protected]> >Cc: [email protected], "Garnier, David S (GE Healthcare)" ><[email protected]>, [email protected] >Subject: RE: Looking for Barometric pressure meter > >In quickly checking the 61000-4-x series that are called out in CISPR >24, IEC 61000-4-2 (ESD) is the only one. Section 8.1.1 calls out the >acceptable climatic conditions for performing the tests, and the >atmospheric pressure must be between 86 kPa and 106 kPa. That's a >range of 25.4 inches of Hg to 31.3 inches of Hg. As standard >atmosphere at sea level is 29.92 inches of Hg at 59 degrees F, and >pressure drops about 1 inch per 1000 feet of altitude gain, you can see >that you hit the minimum pressure on a standard day at 4520 feet. >Denver is at 5280 feet (one of the steps on city hall). Not sure how you can "legally" >perform ESD testing in EMC labs in most of Colorado. :-) - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] 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] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] 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] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] 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] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
