My first choice would be to test floor standing products sitting 0.1 m above the ground reference plane (GRP) on a support and don't consider the casters.
However, some floor standing equipment is very heavy and can be difficult if not dangerous to try and pick up to set it on a 0.1m support. In those cases you just have to do the best you can and document the alternate setup in the test report. Beware that some casters are conductive. Years ago we found out the hard way that black rubber wheels and pads (under feet) can be conductive. So always use an insulator between them and the GRP. What some labs are doing is to take one of their work stations and sink the GRP 0.1m below the floor level with non-conductive materials on top of the GRP to bring the surface level with the rest of the floor in the lab. This would be a dedicated test area for Floor Standing equipment. You just roll the equipment in and test. You still need access to the GRP to bond your CDNs and Burst Test Generator, but this really makes the setup easy. If you cannot sink your GRP, some labs build up an area on top of their GRP and have a ramp to roll floor standing equipment onto. Again, with some large and heavy products this can be dangerous. Have fun. The Other Brian -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of T.Sato Sent: Friday, May 24, 2013 10:12 AM To: [email protected] Subject: IEC 61000-4-4 test setup for EUT which have casters Colleagues, Maybe a slightly silly question, but I want to hear your opinions. IEC 61000-4-4:2012 clause 7.3.1 says: Floor standing EUTs ... shall be placed on a ground reference plane and shall be insulated from it by an insulating support with a thickness of (0,1 +/- 0,05) m including non conductive roller/casters (see Figure 11). When testing EUTs which have commonplace casters (caster which has plastic wheel and metal hub and supporting structure) under it, will you treat the casters as part of the required 0.1 m height insulation support, or will you still put the casters on 0.1 m insulating support? In the former case, what if the casters were higher than 0.15 m? In the case of IEC 61000-4-3:2006, it says that "Non-conductive rollers may be used as the 0,05 m to 0,15 m support" but it also says "... the support shall be bulk non-conducting, rather than an insulating coating on a metallic structure.", so I think we should put the casters, which have plastic wheel but metal hub and metal supporting structure so probably not "bulk non-conducting", on 0.1 m insulating support in this case. Regards, Tom -- Tomonori Sato <[email protected]> URL: http://homepage3.nifty.com/tsato/ - ---------------------------------------------------------------- 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://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. 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]> ________________________________ LECO Corporation Notice: This communication may contain confidential information intended for the named recipient(s) only. If you received this by mistake, please destroy it and notify us of the error. Thank you. - ---------------------------------------------------------------- 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://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. 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]>
