On Thu, Jun 4, 2009 at 7:23 AM, Todd Lyons <[email protected]> wrote:
> On Wed, Jun 3, 2009 at 6:34 PM, Jeff Lasman <[email protected]> wrote: > > Good info here: > > > http://sci.tech-archive.net/Archive/sci.electronics.design/2005-02/5165.html > > But that was 2005, this is 2009, and UPSes using stepped square waves > > come with $10,000 equipment warranty. > > So have things (like design issues) fundamentally changed? > > Everything modern uses high frequency switching power supplies (unless > you're like Gibson and got a PDP-8 :-). So when you talk about > stepped square waves, are you talking about PWM (Pulse Width > Modulated) output? That's par for the course nowadays. > high frequency switching PSU's have been around for a while now. Also, it's not PWM, it's sine wave approximation by phase switching/filtering, and the closer it gets to a real sine wave on the output, in battery mode, the more expensive the UPS. > > -- > Regards... Todd > _______________________________________________ > LinuxUsers mailing list > [email protected] > http://socallinux.org/cgi-bin/mailman/listinfo/linuxusers >
