An extra point on this subject is to remember that hydraulic hoses usually have a metallic reinforcement below the rubber. Therefore all the effects previously mentioned for co-ax cable are true for hydraulic hoses as well. i.e. Broadcast signals will be pouring into your chamber, and your RF immunity levels will be pouring out of the chamber. We try to use hydraulic thru connectors which we fit to the penetration panel mentioned in Ed's article. Luke Turnbull Dr Luke Turnbull EMC Technical Manager TRW Conekt Stratford Road Solihull West Midlands B90 4GW
Tel: +44 (0)121.627.3966 Mobile: +44 (0)7730.671284 Fax: +44 (0)121.627.4353 email: [email protected] web: www.conekt.net >>> "Gert Gremmen" <[email protected]> 14 January 2009 06:03 >>> The grounding of the shield of your antenna cable simply should be considered mandatory. There is no way you can exclude environmental (radio) signals to leak in otherwise, and there is no way of preventing high power immunity test signals to leak out. With leaking I mean at the attenuation will be less then 6dB or so. A cage of faraday with the shield broken this way will have its shielding effectiveness drop from over 100 dB to 3-4 dB at its best. Whether you use bulkhead connectors , or other means to ground the shield, keep in mind that the only place you should do the grounding is exactly at the physical boundary of the chamber. A few cm of cable run outside or inside between ground and pass through will have the same effect as above, possibly limited to higher frequencies. Feel free to elaborate on this topic if you think you need to. Gert Gremmen Van: [email protected] [mailto:[email protected]] Namens [email protected] Verzonden: dinsdag 13 januari 2009 22:50 Aan: [email protected] Onderwerp: Anechoic Chamber: Pass-through vs. Bulkhead EMC Gurus, We have a Space Saver chamber that we bought used and installed ourselves. When we installed it, we ran our antenna (signal) cabling through a pass-through along with our fiber optics. Today, someone mentioned that we ought to have at least our antenna cable connected through a bulkhead so that the cable shielding was terminated on the chamber. When we went to disassemble the chamber when we bought it, there were no bulkheads for anything. Are the bulkheads necessary? Does anyone else use a pass-through for the antenna cable? It doesn't seem to have had an effect on measurements, but I still have a lot to learn so hopefully someone can share some wisdom. Thanks, Chris Anderson - 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://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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher <[email protected]> David Heald <[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://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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher <[email protected]> David Heald <[email protected]> Conekt is a trading division of TRW Limited Registered in England, No. 872948 Registered Office Address: Stratford Road, Solihull B90 4AX - 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://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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher <[email protected]> David Heald <[email protected]>
