Ok Greg, funny enough now that I tested it with my laptop battery discharged to ~20%, I got completely different #s today:
As it's charging up I saw a .99 PF at .9 Amps and 105VA and thus 105watts! And now that the battery is fully charged I'm seeing a PF of .97 or so (.95-.99) at .5 Amps and 57VA and thus 55 watts... So any idea why/how I'm getting a PF of ~.97 or so when I was getting .5 or so yesterday?! Or is my Kill A Watt broken (which I don't think it is)? Nothing I read online so far explained why a power supply would vary so much, especially since it's obvious that it IS a PFC PS after all since if it wasn't, it wouldn't be capable of such a high PF... Curious and just trying to learn... (Hoping this gets formatted correctly too-trying it from Firefox which I realized I hadn't tried yet-tried IE9 and Chrome-woulda thought Chrome would've been fine... :P) > From: [email protected] > To: [email protected] > Date: Mon, 1 Aug 2011 18:00:45 -0500 > Subject: Re: [H] PFC (power factor corrected) PS for PCs? > > If you're trying to find max load, I would encourage discharging the battery > to 60% or so and re-installing it, and then stress the internal components > to 100%. Keep in mind that your power adapter needs to not only power the > system itself, but also the battery charging circuit. Your worst case load > will be doing 100% utilization while charging a depleted battery. > > > -----Original Message----- > > From: [email protected] [mailto:hardware- > > [email protected]] On Behalf Of Anthony Q. Martin > > Sent: Monday, August 01, 2011 5:09 PM > > To: [email protected] > > Subject: Re: [H] PFC (power factor corrected) PS for PCs? > > > > The input is the (rms) voltage (fixed, depending on where on the planet > > you are) and max current expected to be drawn from the wall socket. > > Those are AC. > > > > The output is DC that comes out of the converter to supply your laptop. > > It would be wise to meet these specs if you replace it, though you could > > probably make it work if you got close (exact on voltage and close on > > current), but you'd better not force the laptop to 100% load. Looks > > like your laptop can draw 120W max. The input (wall) can easily simply > > that @ 2A. > > > > The pf of 0.5 isn't bad according to your power company since you draw > > comparatively tiny current and power and your leads are short, so > > you're not losing huge amounts of power to heating wires and stuff. From > > a purely 'green' POV, it could be considered bad...but you also have to > > consider the cost of PFC on a unit like your laptop. Probably not much > > to gain by it. > > > > Draining the battery won't cause your laptop to draw max power. For > > that you need to load it up with some benchmark that drives the HDs, > > CPU, and GPU as hard as possible. You could even remove the battery and > > draw power straight from the wall socket. No good reason to stress the > > battery. > > > > Yes, if you expect to run your machines at max load then you need to > > budget accordingly. I don't run my machines at max load, though, so I > > can get lots more time from a UPS than would be indicated by using max > > load conditions. > > > >
