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Old 02-19-2008, 04:41 PM   #24 (permalink)
H4MM3R
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True Power

Quote:
Originally Posted by newtonsfirstlaw View Post
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.
The newer kill-a-watt will display power factor. However it really doesn't matter. Your Power Factor should be 1 or very very close to 1. What most people are looking at in there homes (in the USA) is 120/240vac single phase.

When calculating Power there two basic ways (1) True Power (2) Apparent Power.

The Kill-A-Watt P4400 can display either one.
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