120v 2.2amp = 264 watts
Compare that to the wattage you measured (>>> 99/136/196 watts) and you can see why I said that whatever the plate says is not very accurate.
120v 2.2amp = 264 watts
Compare that to the wattage you measured (>>> 99/136/196 watts) and you can see why I said that whatever the plate says is not very accurate.
This is not watts; it's volt-amps.
You should compare it to the volt-amps he measured. Then it's not so far off.
You are making a mistaken assumption. If you measure the current draw (amps) and the applied voltage separately, and multiply them, you get the (real) watts consumed *only* if the load is a pure resistance. If the load has a reactive component (inductance or capacitance; in this case the motor is an inductive load), then the product of volts and amps is the "apparent power" (volt-amps), not the "real power". See:
An incandescent light bulb, electric stove, electric toaster or electric blanket would be an example of a pure resistance load. Most household equipment other than heating devices, if they have motors (refrigerator, for example) or non-PF corrected power supplies (older computer or television) will have a power factor of less than 1, and will require a special type of meter (a wattmeter) to measure their real power consumption (because the load has a so-called "wattless" component):
As they say on that page, "On an ac circuit the deflection is proportional to the average instantaneous product of voltage and current, thus measuring true (real--my addition) power, and possibly (depending on load characteristics) showing a different reading to that obtained by simply multiplying the readings showing on a stand-alone voltmeter and a stand-alone ammeter in the same circuit."
Go back and look at Bill's earlier post where he gives the result of his actual measurements:
"99/136/196 watts
129/175/248 volt-amps at 121 volts"You'll see that volt-amps and watts are substantially different. This is the beauty of the Kill-A-Watt. It measures both the apparent power and the true power. The apparent power (the product of separately measured amps and volts, remember) will be larger than the true power with a fan motor load, but the true power reading is what you pay for on your electric bill (if you're a typical residential customer). Large industrial customers pay a penalty if the apparent power they consume is larger than the true power, but ordinary residences don't.
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