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Unread 21-08-2014, 14:08
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SeanFitz SeanFitz is offline
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Re: Which Gearbox Should I Use?

Quote:
Originally Posted by Oblarg View Post
I don't know how detailed the calculator you're using is, but that sounds realistic. That's not at all a worrisome number, either - the FRC breaker can take 155 amps for essentially a whole match. During the times last year when our robot was not running into problems, we were pulling ~180 amps in pushing matches, and that was about the worst-case possible while still slipping the wheels. It was when we got near the 240-amp mark that things went south, and I only ever saw that type of current draw when the motors were stalled. You will not stall your drive motors when geared for 5FPS, barring some sort of cataclysmic failure.

Make sure that if you're going for a 4.8FPS gearbox that it's a two-speed. That's far too slow to function well as a single-speed drive.
The link for the calculator is here. If I'm reading it right, with a VEX 3-CIM ball shifter (yeah, it will be two-speed) with a 3.68 spread and a 24-60 third stage, the total amps at max are 155, but that's with a 1.4 wheel cof. Take a look and see if the calculator looks right.

On another note, what did you guys use for wheels last year? Is there anything you would change?
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