Muriel, Now this depends on the size of the equipment but the easiest solution would be to build a cage around the equipment and screen the test. This can be a very simple wooden frame covered with chicken wire or similar. Since we're only talking about conducted emissions, presumably up to 30MHz size of the mesh is not critical. The main points to remember are: 1, The enclosure should be 0.5 m larger than the equipment on all faces. 2, All cable screens entering or leaving the enclosure should be tied down to the same potential as the enclosure. 3, The enclosure should be earthed. 4, The incoming mains should, preferably be filtered. Whatever you do don't simply pass any cables through the wire and into the test volume as this negates the efficacy of the faraday cage!.
Good Luck Ian Ball Dedicated Micros UK ---------- From: Muriel Bittencourt de Liz[SMTP:mur...@inep.ufsc.br] Sent: 22 September 1998 21:35 To: Lista de EMC da IEEE Subject: Doubt on Measuring with Spectrum Analyser Hello all, I'm doing my measurements of conducted emissions using a Spectrum Analyser, but my site isn't shielded, i.e. some interferences ( radio stations ) appear at the screen of the SA. So, i'm doing this: i record the signal with the product tested at "off" and when i turn the product "on", i subtract the signal of "on" minus the signal of "off". this means that i subtract the "ambient noise" from the noise being generated by the product itself. What i really want to know is: is this procedure correct? am i doing a nonsense thing? Any comments will be welcome. thanks Muriel -- ================================================== Muriel Bittencourt de Liz INEP - Instituto de Eletronica de Potencia Universidade Federal de Santa Catarina Caixa Postal - 5119 88.040-970 - Florianopolis - SC - BRASIL Phone: +55.48.331.9204 - Fax: +55.48.234.5422 e-mail: mur...@inep.ufsc.br Homepage: http://www.inep.ufsc.br ================================================== --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
