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Old 01-11-2008, 01:52 AM   #6 (permalink)
newtonsfirstlaw
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Join Date: Dec 2007
Location: Melbourne
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The Mighty Mira - '92 Daihatsu Mira
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Quote:
Originally Posted by bennelson View Post
I have noticed the Killawatt seems to be inaccurate at low wattage.

Does anyone know of another product that would be good for measuring low current AC? Something inexpensive, or better yet, a DIY project for how to make one?
Well, seeing as most people use the Kill-a-Watt about once, which is when they audit their house and write down figures for on and turned off, it's easy to just use the Kill-a-Watt.

The trick (not sure if I made it clear) is to measure what you want to measure in parallel with another, bigger, purely resistive load. The difference (with the resistive load on, and the smaller device in question on/off) will be the power draw of the smaller device. Yes, I know that taking power factor into consideration, it won't be exactly correct but it will be close enough.
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