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Unread 14-02-2012, 09:48
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Re: Determining Motor Speed?

Quote:
Originally Posted by 45Auto View Post
Our dual 775's running through cim-u-laters freespin our 8" wheel up to just over 3600 RPM, as measured with a photo-tach.

free speed of 775-12 at 12 volts is 7300 rpm. CIM-U-LATOR gear reduction is 2.7:1

7300/2.7 = 2704 rpm So you can't be using 775-12.



free speed of 775-18 at 12 volts is 13000 rpm

13000/2.7 = 4800 rpm

3600/4800 = 75%

775-18 at 12 volts at 75% speed is drawing 23 amps, and cranking out over 200 watts. And you say you have 2 of them. Something doesn't add up.