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Comparative Power/Weight Ratio

Comparative Power/Weight Ratio

Comparative Power/Weight Ratio

(OP)
Is it correct to say that, given a common set of criteria, a heavier (larger) motor will provided a greater power/weight ratio then that of a smaller motor?

The criteria would be that of a modern high performance motor that is brushless, has rare earth magnets and perhaps is an outrunner.

Thanks,

Dave J.

RE: Comparative Power/Weight Ratio

Not sure you can say that.

Some smaller motors could easily have a higher P/W ratio.  They can afford to have those exotic magnets.  They don't need massive shafts and mechanical structures to transmit the power.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Comparative Power/Weight Ratio

Many small motors achieve seemingly outrageous power outputs due to their very high rotational speed. Most big machines are limited to 3000 or 3600 rpm, and although higher speeds are possible the physical limitations of the materials the rotor is fabricated from prevent such high speeds being achieved with very large machines.
 

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RE: Comparative Power/Weight Ratio

(OP)
Keith, Scotty;

Thanks for the replies.

Dave

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