Unlike the US/Canada (etc), there is no derating factor for UK mains wall outlets. A 13A wall outlet can be loaded at 13A, and a twin/duplex 13A outlet can be loaded at 13A per outlet because the "diversity factor" principle is applied, i.e. it is highly unlikely in practice that both 13A outlets will be actually be fully loaded at the same time!
Murphy's Law may however apply at times in that both outlets could simultaneously be loaded at 13A - and so it is to be hoped that the wall outlet in question is on a UK "ring main" circuit protected by a 32A breaker, and not a spur/radial/branch circuit protected by a 16A breaker! For a power strip plugged into one of those outlets, there is a (generally, as John W said) a 13A fuse in the plug, and so the max cumulative continuous load for the sockets in the strip is also 13A - unless, of course, the mfr has decided to give it an overall lower current rating, fitted a lower-rated fuse AND marked the plug with that rating. BTW: I have also occasionally seen 7A fuses (the fuse standard is BS1362, but, AFAIK, that only shows a few "standard" ratings, and not some of those which are actually sold - such as those listed here http://cpc.farnell.com/search?st=plug%20top%20fuse) I believe that the standard for such UK power strips is probably BS 5733:2010+A1:2014 "General requirements for electrical accessories. Specification" - but don't have a copy and so can't comment in detail on what it requires. John Allen W.London, UK From: John Woodgate [mailto:jmw1...@btinternet.com] Sent: 15 September 2017 07:36 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] power strip details UK household power strips are rated at 13 A and include a 13 A fuse. Other fuses, normally used in plugs, are 3 A, 5 A and 10 A. I have seen a 1 A fuse, but they are very rare. With best wishes DESIGN IT IN! OOO - Own Opinions Only www.jmwa.demon.co.uk <http://www.jmwa.demon.co.uk/> J M Woodgate and Associates Rayleigh England UK is a sovereignty, not a Zollverein-ty From: Pete Perkins [mailto:00000061f3f32d0c-dmarc-requ...@ieee.org] Sent: Friday, September 15, 2017 5:55 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] power strip details Esteemed colleagues, Here in North America a domestic or commercial multi-outlet power strip would be cord connected thru a duplex outlet protected by a 15A (or sometimes 20A) circuit breaker. The max load allowed in the circuit by the US NEC would be (80% of 15A) 12A for the total load (or 80% of 20A) 16A on the 20A breaker. Note that the US NEC requires that any device plugged into a duplex outlet must not use the full load capacity of the circuit - 20% must be left for the other outlet's load. Trying to understand the loading basis for a Euro power strip. Is the usual protection a 10A breaker? And would the power strip be rated and evaluated at that load level? What other considerations come into play here? How about a UK power strip. The usual protection is the 13A fuse in the power plug (altho smaller values seemed to be used also). Would the power strip be rated and evaluated at that load level? What other considerations come into play here. For a Japanese power strip what is the normal breaker protection for the installed circuit? What would be the max rated load for the power strip? What other considerations come into play here also? Looking forward to your replies on this issue. :>) br, Pete Peter E Perkins, PE Principal Product Safety & Regulatory Affairs Consultant PO Box 23427 Tigard, ORe 97281-3427 503/452-1201 p.perk...@ieee.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.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://www.ieee-pses.org/list.html (including how to unsubscribe) <http://www.ieee-pses.org/list.html> List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <sdoug...@ieee.org> 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. 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.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://www.ieee-pses.org/list.html (including how to unsubscribe) <http://www.ieee-pses.org/list.html> List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <sdoug...@ieee.org> 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. 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.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://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <sdoug...@ieee.org> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
