Quote:
Originally Posted by mans
I was concerned about this...
An electrical engineer is telling me resistors work by wasting off the extra electricity into heat.
if thats the case the motor would use 7 amps regardless of the control knob setting, as at full power none would be wasted to heat, and the lower you go the more is turned into heat...
but when u put an ammeter to the car you will see that power draw DOES go down when u turn down the control knob.
This difference between what I find in actuality and what the electrical engineer tells me is confusing.
can anyone shed some light on this one?
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It's all there in Mort's post #7. The power consumed (wattage) remains the same, but the amperage through the fan motor drops to half if the resistance in the circuit doubles by your adding resistors.
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Darrell
Boycotting Exxon since 1989, BP since 2010
Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac? George Carlin
Mean Green Toaster Machine
49.5 mpg avg over 53,000 miles. 176% of '08 EPA
Best flat drive 94.5 mpg for 10.1 mi
Longest tank 1033 km (642 mi) on 10.56 gal = 60.8 mpg
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