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Old 08-27-2014, 02:18 PM   #1019 (permalink)
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What accuracy does the Fluke have? Can id display 0.31 or 0.315 ohms?
The Multimeter is a Fluke 179. If I measure a 1K resistor, I'll get a result like 0.997kOhms. A very low resistance like the motor windings is simply 0.3 Ohms.

Regarding carrier frequency, one issue is simply audible noise. One way to avoid an audible whine is to move the carrier frequency above the human hearing frequency range, like 18 kHz or 20 kHz. (probably lower for those of us who went to too many rock concerts...)

Paul had a great discussion about a "moving" carrier frequency on the EV tech list. If done correctly, this can result in a much less annoying variable hiss - type sound. I would definitely say Paul is a much more qualified person to answer those issues.

Also, Oak Ridge Labs has a lot more interesting tests than the ones I posted. It's definitly worth it to see what they've been up to.
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