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Unread 18-02-2012, 08:00
iambujo iambujo is offline
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Re: Gear ratios for launcher

Quote:
Originally Posted by Ether View Post
2250 * 3.67 = 8258 motor RPM

0673 @ 12 volts @ 8258 RPM is pulling 68.5 amps and generating 512 watts of waste heat.

This seems like it would either trip a breaker or smoke the 0673.

Are you sure of your numbers?


I was pretty certain until you put it that way. It doesn't appear to run very hot so far. I can certainly check the current today by measuring the voltage drop across a high wattage, low resistance power resistor in series.

I have seen plenty of shooters on CD this year with the same kind of setup - AM gearbox, FP motor, aiming for about 3 to 5,000 RPMs. If your concern is correct aren't we all in the same boat? If not, any idea where my assumptions have gone wrong?
Thanks!