"Wilton Helm" <[email protected]> wrote: >>A modern switched mode PSU ought to be more than 90% efficient,
>In theory, yes, in practice, not likely. It is harder to get high >efficiency from an isolated supply than a non-isolated one. I get ads >from IC manufacturers all the time about there 90 to 95% efficient >solutions, but these are boost or buck regulators--non-isolated. State >of the art in commercial practice for isolated supplies is around 80 to >85%, and typical commercial practice is more like 70 to 80%. The per-port regulators would be non-isolated. Probably feeding off an internal 48V bus. >Now you >have more like 60 watts of heat radiating from this power supply. Go >stick a 60 watt light bulb (incandescent) in a small metal box and see >how easy it is to keep cool. Well, the bulb has a peak permissible operation temperature of about 160 degrees C ... so likely no extra cooling required. :-) -- /"\ Bernd Felsche - Innovative Reckoning, Perth, Western Australia \ / ASCII ribbon campaign | Religion is regarded by the common people X against HTML mail | as true, by the wise as false, and by the / \ and postings | rulers as useful. -- Seneca the Younger _______________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
