If you analyze most UPS's output on battery mode with an oscilloscope, the wave is squared due to the nature of the inverter/switching circuit that makes the AC voltage out of DC voltage. Even though the computer power supply converts AC to DC and has multiple filters, in the past, especially with audio applications, there were some harmful interferences.
Big part of the problem though relies on the inverter switching at the moment of power failure, so the most expensive UPS's run on battery all the time and the charging circuit is always on. These are the online UPS's. This is some of the knowledge I had from many years ago, but I don't think there were major changes to that, other than power supplies being much more efficient and somewhat more immune to noise. On Wed, Jun 3, 2009 at 6:32 PM, David Kaiser <[email protected]> wrote: > You're saying there is an option to not using sine wave? Aren't sine > waves the crux of alternating current? I have no idea if there is any > usable products or devices that work against square wave power - do you > have some firsthand knowledge of this? Are these square-wave products > cheaper or something? For those of us that are not data-center junkies, > can you provide us some additional information? > > > On 6/4/2009, "Jeff Lasman" <[email protected]> wrote: > > >I run my office on four UPS units; all APC smart-UPS with full sine-wave > >output. > > > >The one running my network failed today, during one of those > >thunderstorms that came through. > > > >I can get it rebuilt, but not by tomorrow (I'm temporarily running my > >network on my main UPS, which is large enough to handle the load, but > >not for long in a power failure). > > > >So I'm looking at replacing it. > > > >Question: years ago the common knowledge was to use sine-wave power > >because it was better for the systems. > > > >The last time I studied this was about the turn of the century; I fully > >realize that things may have changed. > > > >So today I'm not sure. What do you think? Any experience? > > > >Thanks for any input. > > > >Jeff > >-- > >Jeff Lasman, Nobaloney Internet Services > >P.O. Box 52200, Riverside, CA 92517 > >Our jplists address used on lists is for list email only > >voice: +1 951 643-5345, or see: > >"http://www.nobaloney.net/contactus.html"; > >_______________________________________________ > >LinuxUsers mailing list > >[email protected] > >http://socallinux.org/cgi-bin/mailman/listinfo/linuxusers > _______________________________________________ > LinuxUsers mailing list > [email protected] > http://socallinux.org/cgi-bin/mailman/listinfo/linuxusers >
