Thread: 2012 motors?
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Unread 25-08-2011, 16:36
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Re: 2012 motors?

Quote:
Originally Posted by lemiant View Post
I don't understand this. If power consumption is linearly related to volume then maximum heat production increases in a cubic curve, while maximum heat dissipation is quadratic, thus a larger motor actually has a harder time dissipating heat.
What makes larger motors better at dissipating heat?
The virtue of the CIM is it's tremendous thermal inertia. It weighs about 2.8lbs whereas the next largest motor (RS775-18) is about 0.7lbs. This allows the CIM to absorb much more heat than any other motor in the kit. In a 2m:15s match it can usually get by no problem.

It also has an aluminum case that probably helps conduct heat away quite nicely, better than the steel cases on most of the smaller motors anyway. They're also bolted to other big pieces of aluminum (tough boxes for one) that are great heat-sinks.

On our arm, there were two RS775-18s, one in a dewalt transmission (plastic) one in a bane-bots transmission (aluminum and steel). The one in the bane-bots transmission ran noticably cooler because it dissipated heat through the transmission well. We did thermographics to confirm:

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