In message <497b1c9c.1c078e0a.65f9.7...@mx.google.com>, dated Sat, 24 Jan 2009, Scott Xe <scott...@gmail.com> writes:
>I am unsure if the mains supply companies follow a July 2005 DTI note >"Electrical Supply Tolerances and Electrical Appliance Safety" points >out that "Though the electrical supply is quoted as being over a range, >it is preferable for power distribution companies to keep supply >voltages as high as possible to minimise current in the supply network >and hence delaying the need to make improvements in the supply >infrastructure to increase current handling capability." This advice seems to me a bit surprising. I suspect that a lot of the load is linear, so that a higher voltage gives a HIGHER current, not a lower current. I will ask some people about that. >Thru recent return record and investigation, the domestic mains voltage >is at a higher side, > or = 250 Vac and the failure return rides up >significantly. The manufacturers design their product at EU rated 230 >Vac and assume the product operates at the highest voltage of 254 Vac >occasionally. Now, the product is operating at the higher voltages all >the time. It results in shortening its life or causing early failure. Now that you know it's happening, you can, and of course should, design with that in mind. -- 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>
