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Unread 13-02-2012, 22:41
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Re: Determining Motor Speed?

Quote:
Originally Posted by Garret View Post
They may actually have a free speed RPM of 10000. But that would be only if the gear ratio really was the 2.7:1 in the cimulator followed by the 1:3 that he is talking about. I don't think that it will ever get that fast though.
You're not suggesting that they're gearing down 2.7:1 and then gearing back up 1:3 are you? What would be the point of that?


But suppose they were.

775-18 free speed is 13000 rpm.

13000/2.7*3 = 14444 rpm.

So if the output is 10000 rpm then the 775-18 would be spinning at 69% of its free speed. It would be pulling 28 amps and burning over a hundred watts of waste heat. (I'm assuming here that the OP meant 10000 rpm at 12 volts; maybe that's not what he meant).

In any event, the tangential speed of an 8" diameter wheel at 10000 rpm is 238 miles per hour.