Ed, I don't recall having seen any articles such as those that you are looking for.
I would however recommend against going the epoxy route. Epoxy is difficult to apply reliably unless you build some special applicator jig. Different operators will apply different amounts as well as all the variability in cleaning, uniformity, etc. You also better hope that a little dab doesn't get in the connector pin field... In addition, Epoxy has both a shelf time and a useable time which can both be (often) violated in production. Even if it works from a 1st article EMC measurement POV, the epoxy may fail in the field from user handling/mechanical stress. ...Marko From: [email protected] [mailto:[email protected]] On Behalf Of Scott B. Lacey Sent: Monday, June 16, 2008 12:13 PM To: Price, Edward Cc: [email protected] Subject: Re: Epoxy Bonding Ed, My first question is the degradation in shielding effectivenesss compared to what? If you are comparing the conductive epoxy to a screw-fastened connection you need to know the exact resistance of both shield paths. I think if you took a good four-wire resistance measurement box-to-box for a typical cable length you could get a good comparison of relative resistance. If one construction had 5% higher total resistance the degradation would be at least 5% at the lower frequencies. I've had fairly good success using two multimeters if a 4-wire unit is not available. One provides the current source (on Lo Ohms) and the other measures millivolts. I use large alligator clips with the measurement clips inside of the ones for current. Scott B. Lacey On 16 Jun 2008 at 8:48, Price, Edward wrote: > > I'm curious about the effect of using a gold (or silver) loaded > epoxy to bond a connector shell to a chassis box. If I measured > a bond resistance of about 1 Ohm from the connector shell to > the chassis, how could I estimate the degradation in shielding > effectiveness (frequency range of interest is about 10 kHz to 5 > MHz)? > > Maybe this has been thoroughly covered in some past > Symposium papers. Can anyone give me a hint about where to > look? Of course, absolutely definitive answers, which allow me > to remain lazy, are also quite acceptable. > > Thanks in advance! > > > Ed Price > [email protected] WB6WSN > NARTE Certified EMC Engineer & Technician > Electromagnetic Compatibility Lab > Cubic Defense Applications > San Diego, CAUSA > 858-505-2780 (Voice) > 858-505-1583 (FAX) > Military & Avionics EMC Is Our Specialty > > - ---------------------------------------------------------------- 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 CONFIDENTIALITY This e-mail message and any attachments thereto, is intended only for use by the addressee(s) named herein and may contain legally privileged and/or confidential information. If you are not the intended recipient of this e-mail message, you are hereby notified that any dissemination, distribution or copying of this e-mail message, and any attachments thereto, is strictly prohibited. If you have received this e-mail message in error, please immediately notify the sender and permanently delete the original and any copies of this email and any prints thereof. - 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
