Leslie Bai wrote: "I also would like to share with you my experience when I did a TCF job years ago when I was working in Singapore.
We know it is not possible to perform radiated immunity testing at the customer's workshop. It is just simply illegal! But how would you verify the machine's radiated susceptibility? ESD gun can help - think about it. Regards, Leslie" Hi Leslie: I am not really sure if an ESD air discharge in situ can form the basis of radiated immunity verification towards a more formal document like a TCF. Radiated immunity tests are performed with a defined modulation (AM or FM) with a 1kHz tone in anechoics. I would have taken the approach of applying the IEC 1000-4-6 or my favourite CS 114 (Bulk Current Loom Injection to 400MHz), noting that predominant EUT susceptibility occurs via cables. This way I would at least ensure that the cables are not susceptible. Such procedures would be more "in harmony" with a legal document like a TCF, because provisions for in situ testing are made. I would also check the emission profile of the box w/o the cables and ensure this it is below the limits. Because, if an EUT emits spurious emissions at a particular frequency, there is a possibility that it would also be susceptible. Lastly, if I did want to verify the transient broadband response of the EUT, instead of air discharge (which is a no-go), I would have attached the recommended radiated coupling loop in front of the Keytek or Schaffner ESD gun to optimise coupling, being near field. I would still not include the results of these findings in a TCF (being a legal document), primarily because this is pre-compliance work and is not in any way related to mandated standards which have been voted upon as acceptable test/verification procedures. Regards Arun Kaore EMC Engineer ADI Limited Systems Group Test & Evaluation Centre Forrester Road, St Marys NSW 2760 P O Box: 315, St Marys NSW 1790 Tel: 61 2 9673 8375 Fax: 61 2 9673 8321 Email: kao...@sg.adi-limited.com.au <mailto:kao...@sg.adi-limited.com.au> --------- 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, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
