When confronted with problems like this, I always try to determine the intent of the particular statement in the test. To me, it is clear that the intent is to fully support the EUT and associated equipment, with cables dropping off the edges of the defined area, as needed. The table should serve this support function and be invisible to RF.
In the case of a small EUT with no cables, the intent is satisfied with a table just large enough to support the EUT. Heck, for something like a digital camera without cables, a threaded plastic rod coming up from the turntable, screwed into the mounting hole in the bottom of the camera, would be sufficient to support it and satisfy the intent. Of course, getting an auditor to understand the intent, as opposed to a literal reading, might be difficult to do. Donald Borowski Senior EMC Compliance Engineer Schweitzer Engineering Labs Pullman, Washington, USA From: Derek Walton <lfresea...@aol.com> To: dw...@acbcert.com Cc: "'Grace Lin'" <graceli...@gmail.com>, "'WNya'" <wendy...@yahoo.com>, "'EMC-PSTC'" <EMC-PSTC@LISTSERV.IEEE.ORG> List-Post: emc-pstc@listserv.ieee.org Date: 10/11/2011 10:12 AM Subject: Re: Table Size in Emissions test Sent by: emc-p...@ieee.org Sorry Dennis, you are not correct. Nominal means: b : of, being, or relating to a designated or theoretical size that may vary from the actual. This is from Websters. As you indicate, there is NOTHING that says it has to be 1 by 1.5m I'm sorry to be so anal about this, but it is happening too much where assessors are assessing to opinions and personal agendas. We must follow the standard. Usually there are MUCH bigger fish to fry than quibbling over something like this I repeat, again, that there is NOTHING that says the table SHALL be 1 by 1.5m. Only then could a deficiency be written. Sincerely, Derek. On 10/11/2011 11:43 AM, Dennis Ward wrote: Both ANSI C63.10 and ANSI C63.4, the typical standards for which ISO17025 accreditation is used, contain the following statement, ?Tabletop devices shall be placed on a nonconducting platform, of nominal size 1 m by 1.5 m, raised 80 cm above the reference ground plane. While a bit more open to variation due to size of equipment, CISPR 22 has the statement ?Equipment intended for tabletop use shall be placed on a non-conductive table. The size of the table will nominally be 1,5 m × 1,0 m but may ultimately be dependent on the horizontal dimensions of EUT. So while you may challenge the accreditation organization, they are correct, your table does not meet the ?nominal? size requirements for at least the two standards ANSI C63.4 and C6310. Other standards may also have the nominal size issue as well. Thanks Dennis Ward Director of Engineering American Certification Body Certification Resource for the Wireless Industry http://www.acbcert.com 703-847-4700 fax 703-847-6888 direct - 703-880-4841 From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Grace Lin Sent: Tuesday, October 11, 2011 4:16 AM To: WNya Cc: EMC-PSTC Subject: Re: Table Size in Emissions test Wendy, When I look for an accredited ANSI C63.4 laboratory, I expect the laboratory has the facility as stated in the standard, including a standard size of the table as defined in the standard. For this reason, unless the accreditation certificate bears a restriction note, I support the auditor's comment. >From the other point of view, many manufacturers' laboratories are for internal use only, including my employer's. For this reason, the auditor may be willing to accept the smaller size of the table. The question is how to determine if the laboratory is for internal use only (for testing certain type of products). An example is Alcatel-Lucent's EMC laboratory in New Jersey, USA. It opens to the general public. With regards, Grace On Mon, Oct 10, 2011 at 7:54 PM, WNya <wendy...@yahoo.com> wrote: Dear Experts, Recently my company went through the first ISO17025 audit. We have a table smaller than the standard requirement of 1.5m x 1m since our products are small, typically 10cm x 10cm x 10cm. The height of our table was 0.8m. The auditor wanted us to change the table size to follow the standard. What does it matter since we never use the extra space on the table? I do agree we must keep to the height requirement since the floor is a ground plane and thus it sets a fixed capacitance to the EUT and also controls the lengths of any attached cables. Can we reject or challenge the auditor's request? Has anyone experience the same situation? 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 < emc-p...@ieee.org> 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 <emcp...@radiusnorth.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com> - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. 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