Gert:
I really don't have all that much experience with EMP testing; in the past 12 years, I have put three systems through HIRF & EMP using the USN facilities at Patuxent River, MD. . System 1 was an airborne instrumentation pod that had a secure data link back to ground assets. We were lucky that the entire airborne portion of the system was contained in a streamline pod, so except for the intentional signal ports and the aircraft power interface, the pod provided complete metallic SE. We concentrated on bandwidth limiting the ports, filtering and limiting the power interface, and on mechanical build of the pod skin. We passed without incident, so it could be argued that we also didn't learn anything. . System 2 was the ground segment of an unmanned airborne vehicle secure data link. This was essentially a pedestal mounted parabolic tracking antenna with some signal processing boxes. During RS103, we found unexpected failures, tracing them to a rotary slip-ring joint on the azimuth axis of the pedestal. The cause was found to be the improper specification of a commercial slip-ring joint instead of the military version (which was carefully shielded). If this hadn't been caught in RS103, I'm sure this would have failed EMP. When a proper, much more expensive (J) joint was installed, RS103 was easily passed and so was EMP. But again, no specific EMP test lessons either. . System 3 was a secure data link that I won't describe. Despite what we thought was careful design, this system had RE102 & RS103 issues. We had to use several different modular power supplies, change the layout of an RF deck, double-shield two cables and use about 20 EESeal connector filters on internal cables. Finally (after a lot of schedule slippage), it went through RE102 & RS103 just fine, but failed one of the HIRF tests. We didn't have a clue, but in talking over the experience, someone said that lots of systems had been failing that one test recently. Hmmm, my suspicious nature came out. After talking in excruciating detail with the test lab personnel, we get them to run some tests with our system partially and then fully shut off, and miraculously, their lab monitor equipment reports another failure. The lab guys worked all night on the equipment test stand, their cabling and the shielded monitor hut, and with no further explanation, we passed the next day. (And that was the very last environmental qualification test to be finished, so many unhappy people began breathing again.) Lesson learned was "oh thank goodness, it wasn't my junk after all; beer for everyone." Ed Price WB6WSN Chula Vista, CA USA -----Original Message----- From: ce-test, qualified testing bv - Gert Gremmen [mailto:g.grem...@cetest.nl] Sent: Tuesday, October 04, 2016 9:50 PM To: Ed Price; EMC-PSTC@LISTSERV.IEEE.ORG Subject: RE: [PSES] When is EMI testing performed? Hi Ed, Can you share with us some typical EMP caused defects, and their cause/fix ? Most of us do not share your experience in this.... Regards, Ing. Gert Gremmen Approvals manager ---------------------------------------------------------------------------- -------- + ce marking of electrical/electronic equipment Independent Consultancy + Services Compliance Testing and Design for CE marking according to EC-directives: - Electro Magnetic Compatibility 2004/108/EC - Electrical Safety 2006/95/EC - Medical Devices 93/42/EC - Radio & Telecommunication Terminal Equipment 99/5/EC + Improvement of Product Quality and Reliability testing Education Web: <http://www.cetest.nl> www.cetest.nl (English) Phone : +31 10 415 24 26 ------------------------------------------------------------------- - ---------------------------------------------------------------- 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>
