On Tuesday 29 May 2007, Dan Halbert wrote: ... > Watts = Volt-Amps IF the power factor is =1. Power factor is based on > the reactance of the load. A purely resistive load has a PF=1. Google > << watts vs volt-amps >> for more info, e.g. > http://www.vabiomed.org/documents/tech0003.htm. > > The power supplies I have measured in servers have a power factor close > to 1. But I have measured consumer machines with a power factor > considerably different than 1. Worth knowing here is that even if you have something with pf=1 you wont get those 1500 watts out of a 1500VA UPS. UPSes are often, what they call, power factor 0.9 or 0.8. This means that you'll never get more than 1200W or 1350W out of a 1500VA UPS regardless of the pf of your load. That said, modern powersupplies I've tested lately have all been better than 0.9 and most even >0.97. /Peter -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 189 bytes Desc: not available URL: <http://lists.centos.org/pipermail/centos/attachments/20070529/c1d08774/attachment-0004.sig>