The requirement is 75% of the points you are using. So for a UFA using 12 points, you can still eliminate 3 of the 12 points when determining if you have a uniform field. The only exception to the 75% rule is for 4 points, where all the points must be with the 6 dB variance limit
BTW, there is also the option of partial illumination when the UFA does not cover the whole product. It takes multiple runs to test the product fully, but gets the job done. Donald Borowski Schweitzer Engineering Labs Pullman, WA From: WNya <[email protected]> To: Charlie Blackham <[email protected]> Cc: "<[email protected]>" <[email protected]> List-Post: [email protected] Date: 09/27/2011 07:46 AM Subject: Re: [PSES] Still on Radiated Immunity Sent by: [email protected] Hi Charlie, I can, at best, eliminate the top rows. My EUT is small but it is tested as a floor standing device, mounted on a wooden structure. Does this means the FUM requirement is 75% of these 12points? Or is it 100% of these 12points? Sent from Wendy.Nya iPhone On Sep 27, 2011, at 10:18 PM, "Charlie Blackham" <[email protected]> wrote: > Wendy > > Have you considered a smaller one? - you can use smaller UFA if EUT size > permits. > > Regards > Charlie > > -----Original Message----- > From: WNya [mailto:[email protected]] > Sent: 27 September 2011 15:10 > To: Charlie Blackham > Cc: <[email protected]> > Subject: Re: [PSES] Still on Radiated Immunity > > The UFA is as per the standard, 1.5x1.5m, 0.8m above GRP > > Sent from Wendy.Nya iPhone > > On Sep 27, 2011, at 9:44 PM, "Charlie Blackham" > <[email protected]> wrote: > >> Wendy >> >> What size UFA (uniform field area) are you trying to create? >> What size are your EUT (i.e. what sixe UFA do you need?) >> >> Regards >> Charlie >> >> -----Original Message----- >> From: WNya [mailto:[email protected]] >> Sent: 27 September 2011 14:28 >> To: [email protected] >> Subject: [PSES] Still on Radiated Immunity >> >> Dear EMC Experts, >> >> I have a 4x3m chamber. I encounter much difficulty to calibrate the > chamber >> every year. I am using a Schwarzbeck 9128DS and a AR systems. >> >> Does anyone know any 'tricks' to 'tweak' the chamber to perfection? >> >> PS: PAMP is 250W, up to 1GHz. >> >> Sent from Wendy.Nya iPhone >> >> - >> ---------------------------------------------------------------- >> 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://product-compliance.oc.ieee.org/ >> 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://product-compliance.oc.ieee.org/ >> 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://product-compliance.oc.ieee.org/ > 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://product-compliance.oc.ieee.org/ 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://product-compliance.oc.ieee.org/ 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]>
