In message <F9673C7F910141C9B8C7FF30574D7290@GPCLLAP153>, dated Wed, 28 Jul 2010, Don Gies <don.g...@alcatel-lucent.com> writes:
>It was unique for that class to have 3 Americans in it, so we took the >opportunity to contrast the American requirement of GFCI protection of >around 5 mA being required at specific locations, versus RCDs operating >at 30 mA and not being sufficient for fault protection (see BS7671, >17th:415.1 and 531.2.5). BS 7671 is quite a 'political' document and its disparagement of RCCBs is a sign of a mistrust of mechanical devices. In practice (well, correct practice), 415.1 and 531.2.5 never come into relevance. I know I feel much safer using power tools outdoors on an RCCB protected circuit that on an unprotected one. The '30 mA' must be considered, for protection against electric shock injury, in the context of the required disconnection time - 0.2 s for TN systems and 0.07 s for TT systems. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK I should be disillusioned, but it's not worth the effort. But I support unbloated email http://www.asciiribbon.org/ - 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...@socal.rr.com> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
