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Unread 14-01-2007, 02:48
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Paul Copioli Paul Copioli is offline
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Re: 2007 Motor Specs

Quote:
Earlier, Rickertsen2 posted a formula for motor output torque using these calculated values:

torque = Kt*(Vin-Kv*rpm)/r

Does anyone know if there is there an advantage to using this formula over:

Torque = (-T0/Wf)*W+T0, Where T0 is torque at stall and Wf is free speed

If so, is there more documentation somewhere that explains how/why this works better?

Thank you,
Chris
The equation using torque constant (Kt) and back EMF constant (Kv) is the theoretically pure way to calculate motor performance. However, most motor manufacturers will not give you all of these numbers. All motor manufacturers will give you stall T, free speed, Stall current, and free current (no load current) and it is all you need to size motors and gearboxes for the job.