Kill-a-watt with battery?

[VirtualLarry]

Just wondering if perhaps anyone makes a cheap kill-a-watt type device with a built-in battery. Not for the AC, but for remembering the settings, like an alarm clock.

I would like to put a meter on a computer at a friend's house, and see how many kilowatts it takes over the month. I've heard that the higher-end KAW devices can do this, but I also heard that if the power goes out, the data gets cleared. I want a device that retains this data, even during blackouts.

 

[Tsavo]

Side question, how accurate are those Kill A Watts?

 

[Emulex]

pretty accurate at 110v; within 10% watts of what the server thinks its using. fun device. i use it to watch charge cycles on phones/laptops/roomba to make sure things are working right. roomba/scooba is notorious for freaking out and not charging. unplug it and plug it back in and it ramps way up properly then tapers down.

 

[HOOfan 1]

Side question, how accurate are those Kill A Watts?

not very accurate with APFC

 

[VirtualLarry]

http://www.amazon.com/dp/B000RGF29Q

Kill-A-Watt new model P4460 has a battery back-up! Just what I was looking for.

 

[ShawnD1]

not very accurate with APFC

Wouldn't APFC make it more accurate? I can't imagine a cheap $20 meter doing much more than measuring current and voltage then multiplying the numbers. With power factor corrected to >0.9, this is pretty darn accurate.