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Unread 12-12-2013, 16:20
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Ether Ether is offline
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Re: MicroControllers at competitions

Quote:
Originally Posted by Al Skierkiewicz View Post
You are asking for a 0.1 ohm/1500 watt resistor.
His post was admittedly somewhat ambiguous, but that's not the way I interpreted it.

I think he wants to insert the shunt in series in one of the motor leads and measure the voltage drop across it to get current.

Aside from questions of FRC legality, the shunt Ryan linked would would work: it would dissipate roughly 7 watts at 133amps:

0.075V/200A = 375e-6 Ohms. 133amps * 375e-6 ohms = ~7watts.

As you have previously pointed out on many occasions Al, instead of a shunt the voltage drop across a length of existing wiring would suffice to get a rough measure of current (for large currents).



Last edited by Ether : 12-12-2013 at 16:40.