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Unread 04-02-2010, 22:20
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Re: AndyMark Nano Break In

Quote:
Originally Posted by AdamHeard View Post
Does anyone know a good way to get current draw using a voltmeter and ohms law?
Yes, of course. I=V/R, right?

So, carefully measure the Resistance of a piece of wire (I think #10 is 0.1 Ohms per foot, but check me on that. Measure several feet, accurately, being sure to subtract the resistance of the test probes). Now you know R

Measure Voltage across R while the motor is running, and do the math to solve for I (in Amperes)

Note that even a small error in R can lead to large errors in I, but this is also good for relative measurements (as in "it's drawing half the current it was drawing before")
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