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Want to verify I'm reading this UPS right; I'm trying to crudely calculate kilowatt hours & cost. I had one of these, so may I assume that utilization of this is from a total of a maximum output of 670Watts? http://www.amazon.com/gp/product/B002MZ ... os_product

I.e. if I had a consistent 50% load, then I'd be using 670*.5 = 335w |||| 335w * hours / 1000 =kWh?

Your procedure seems correct, with 'crudely' being the operative word. The UPS is actually rated for 1000VA, and might be reporting the percent loading on that basis, whereas the maximum watt-rating of the connected equipment will vary with power factor. 670W assumes a very lousy power factor, which is certainly possible with switchmode supplies, but might be better than that (especially if your computer PSU has an active PFC cirucit). How the UPS then handles that load versus what it pulls at the wall will determine the power usage you're getting billed for by the provider.

You might want to pick up a basic Kill-A-Watt meter (it's cheap, and every techie should have one anyway) and connect it between the UPS and the wall, to see what "50% load" actually looks like after going through the UPS hardware.

Thanks Ludi.

Always thought about one, never bought. Any suggestions on products/brands?

Kill-A-Watt *is* a specific brand and model. Well, actually the brand is P3. But pretty much everyone just knows it as "the Kill-A-Watt". It's the de facto standard for inexpensive powerline wattage measurement devices.

There are a number of Kill-a-Watt models. This is the cheapest one. I paid $17 when it was offered as a combo deal.

I have a Watts Up. (What is with all these bad puns? ) Got that as a gift. But I've dealt with kill-a-watt's as well, and they're pretty solid. Definitely nice to have.

Note: amazon has the killawatt for a few bucks less. Depends on if you want to deal with their tendency to be slow as hell at shipping things as of late (even if you pay for Prime apparently).

just brew it! wrote:

Kill-A-Watt *is* a specific brand and model.

I use a Seasonic "Power Angel" (about $20 delivered). I've tested, at the low-end, against an LED desk-lamp, and at the high-end, against a window-mounted air-conditioner. Both came in within a few percent of what was expected based on their specs, so I believe it across it's whole range.

I most recently used it to test an Asus RT-AC68P, which shows 8W with both radios enabled, more than I expected/hoped.

JustAnEngineer wrote:

There are a number of Kill-a-Watt models. This is the cheapest one. I paid $17 when it was offered as a combo deal.

Ahh, OK. I was not aware that there were other models of power meter in P3's Kill-A-Watt line. The basic Kill-A-Watt is the only one I've ever seen mentioned (and is the one I have).

Ok Ok, bully me into it! Probably going to nab this when I get home today: http://www.amazon.com/P3-International- ... =killawatt

Doesn't look like anything that will cheaply measure 220 (240) too.

Nerd shaming worked--I did end up buying that meter. Pretty useful tool to have. Said rebuilt server of mine with dual processors eats about $25/month in juice

zhuhaiping wrote:

they're pretty solid. Definitely nice to have.

Hmm, not sure why we're bumping an old thread... But - somehow I find myself slowly building up a collection of all sorts of tools as time goes on. Soon after I got a car, my tool collection slowly started expanding into that realm as well. Computer parts, multimeter, wrench set, torque wrench, OBDII reader, outlet tester, etc. And it all goes to good use. Something's acting up? Even if I don't know how to fix it, I at least want to try and figure out the issue. How do average people live without these things?