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Unread 18-02-2014, 17:59
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Ether Ether is offline
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Re: Stalling an RS775

Quote:
Originally Posted by JamesCH95 View Post
Can't find the internal resistance spec for a 775 off-hand...
The FRC 2014 motor spec says:

RS-775-18 stall current = 87 amps -> R = 12/87 = 0.138 ohms

RS-775-12 stall current = 30 amps -> R = 12/30 = 0.400 ohms.


So, for 10 watts input power, the RMS voltage at stall would be given by:

V = sqrt(P*R) = sqrt(10*0.138) = 1.17 volts for the 775-18 for 10 watts

V = sqrt(P*R) = sqrt(10*0.400) = 2.0 volts for the 775-12 for 10 watts.



Last edited by Ether : 18-02-2014 at 18:02.