In message <201048ea81ba0745aca78e4cc883900104781...@desmdswms201.des.grplnk.net>, dated Fri, 27 Mar 2009, "Haynes, Tim (SELEX GALILEO, UK)" <tim.hay...@selexgalileo.com> writes:
>Does this change the circuit for SELV to PELV and I thought that PELV >and SELV circuits could not be "mixed and matched" as the SELV circuit >safety is partially dependant on there NOT being an earth? That is indeed the 'phlogiston theory of electrical safety'.(;-) How can adding a THIRD safeguard to an SELV source make it unsafe? I suspect that somewhere in the history of SELV, 'no earth is required' was modulated into 'no earth shall be present', for no reason. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk Things can always get better. But that's not the only option. John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - 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://www.ieeecommunities.org/emc-pstc 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...@ptcnh.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>