Where is limited power/voltage/current required for Class II construction ? Did you intend to say Class 2 power source ?
luck, Brian From: emc-p...@ieee.org [mailto:emc-p...@ieee.org]On Behalf Of Curt McNamara Sent: Friday, May 02, 2008 7:38 AM To: ted.eck...@apcc.com Cc: emc-p...@ieee.org Subject: Re: Safety regulations Wow! The chart shows 2A at 45V for Class II, or 100VA as you note. This is a lot of energy to me, and can certainly result in ignition given the correct conditions. I note that the standard also shows voltages above SELV as permissible. The implication in the original question was information technology (as far as I could tell). Even with approved supplies and only SELV levels safety investigations are still required. Some examples: Flammable material (the laptop plastic case). Fault (5V to ground) causes part to fall off board through vent hole, igniting material on table. There are lots of ways to design unsafe products using only SELV (not even considering Class II). If your product needs a safety approval then an investigation is required. To phrase this another way: someone else's label (the power supply manufacturer) is not a valid indicator that a product has a safety approval. Curt For help, send mail to the list administrators: - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.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: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
