Mike,
Your comments can't be over stressed any more. We did find the deviation between correlations from products to products, however, as long as a suitable harness is used properly, the correlation is pretty consistent. Also we use modeling tools to assist correlation prediction. It helps as well. I am wondering if it is a mandatory to correlation GTEM cell result with OATS result for each of EUT, why we have to duplicate the test, why not just get the result from OATS to comply. For immunity test against CE using GTEM, it is stated in EN61000-4-3, Annex , as an alternative test facility. For emission test, as mentioned above, ANSIC63.4 accept GTEM result. EN has no specific standard such as EN55022 to accept GTEM result. However, compliance can be declared through TCF route against generic standards as allowed by EMC Directive. I personally have no doubt GTEM and also things like Reverberation Chambers (another alternative facility) will be fully recognized eventually, it's just the matter of time. Rgds, Leslie --- Mike Hopkins <mhopk...@keytek.com> wrote: > > Careful -- for FCC emissions it's allowed only if > correlation with an OATS > is achieved for a given product. For the next > product, correlation may have > to be re-done. > > For immunity to EN's, it isn't so clear. IEC > 61000-4-3 is written as if any > type of TEM cell is NON compliant, but a draft annex > is now being circulated > that would allow TEM cells, but ONLY if a TEM wave > can be demonstrated > throughout the frequency range being used (3-axis > measurement, undesired > vectors > 6 db down). > > For emissions to EN's, TEM cells are not allowed for > compliance testing. > > Mike Hopkins > mhopk...@keytek.com > > > -----Original Message----- > > From: Leslie Bai [SMTP:leslie_...@yahoo.com] > > Sent: Wednesday, July 07, 1999 11:25 AM > > To: Qu Pingyu; 'emc' > > Subject: Re: GTEM cell > > > > > > Pingyu, > > > > I guess GTEM cell is a good choice for your case. > > Pls refer to IEC61000-4-3 (for immunity) and > > ANSI C63.4 (for emission), GTEM cell is not only > > recognized for pre-compliance test but also > > can be used for compliance test as long as > > some correlation can be achieved. > > We did correlation through both modeling, > simulation > > using FDTD and actual testing to verify the > results. > > We are using GTEM cell for many different kinds of > products > > compliance test and PCB trouble-shooting. > > It is pretty good. But you have to pay attention > > to the uniformity volume of GTEM cell, it's > > a bit tricky, especially the cabling of EUT may > affect > > the result, thus, during the correction, a harness > > is supposed to be used to simulate the EUT > cabling. > > > > Hope it helps. > > Leslie > > > > --- Qu Pingyu <pin...@ime.org.sg> wrote: > > > > > > Hello, Everyone: > > > > > > I have some questions regarding the GTEM cell. > Here > > > in our Institute we are > > > considering setting up some EMC measurement > > > capability for precompliance > > > testing. The EUTs we are dealing with are not > very > > > large, probably not > > > larger than a desktop PC. Do you think that GTEM > > > cell is a good choice ? Do > > > many of you use GTEM as a precompliance testing > > > facility ? Your comments are > > > highly appreciated. > > > > > > Regards > > > > > > Qu Pingyu > > > > > > > > > --------- > > > 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). > > > > > > > > > > > > > > _________________________________________________________ > > Do You Yahoo!? > > Get your free @yahoo.com address at > http://mail.yahoo.com > > > > > > --------- > > 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). > > > > --------- > 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). > > > _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com --------- 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).
