I read in !emc-pstc that bruce maule <bruce.ma...@alliedtelesyn.co.nz> wrote (in <se5cab2b....@leo.alliedtelesyn.co.nz>) about 'AC feed fail changeover relay' on Wed, 26 Feb 2003:
>I believe that this scenario is reasonably common, from talking over with our >electrical safety test lab, but the solution of using a single relay as the >changeover element may not be viable. You can use a relay with two normally-open and two normally-closed contact sets. Provided the insulation between the contact sets meets basic-plus-supplementary or reinforced requirements, you can wire the supplies through two contact sets in series. The contact gaps when open may need to be 3 mm or some other minimum length, depending on your national regulations. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
