Dear Colleagues We are a manufacturer of audio mixing consoles with a range that varies from A4 size up to large 2m long 2 man lift consoles. Most have internal ac/dc power supplies. We are researching changing the way we power are future products to rationalise the psu range as worldwide approval costs increase. One of the options is to purchase 60-80W PC laptop power supplies and power the smaller mixers from the DC output of the external laptop supply. The DC output voltage from a laptop PSU is typically 19V. However; most mixers require typically +/-15V, +10V & +48V internal voltage rails. We propose to buck regulate the +/-15V and +10V rails & boost the +48V rail from the 19V DC input. If the total power consumption of the mixer was no more than 80W and the +48V was current limited to no more than 1 Amp, would the mixer require approval testing for north America or any other country as the input voltage would only be 19V DC. Obviously the external ac to dc laptop power supply would have all the necessary approvals; probably to IEC60950 and be class 1 construction.
Your opinions would be appreciated. Thank you in advance; Ian McBurney Design Engineer Allen & Heath Ltd Kernick Industrial Estate Penryn, Cornwall TR10 9LU United Kingdom +44 (0)1326 370121 [email protected]<mailto:[email protected]> www.allen-heath.com<http://www.allen-heath.com/> A DMH Pro Company<http://www.dmh-global.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 <[email protected]> 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://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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
