RC-Monster Forums - View Single Post - anyone know how to figure out how to figure out the motor resistance in Ω

BrianG · 09.26.2008, 12:36 AM

Finding the DC resistance would take some special equipment if it's not listed. This is the resistance of a stalled motor.

And the inductive reactance will vary with frequency and rotor movement.

The DC resistance will always be VERY low, but isn't really useful for general calculations. For instance, a motor could easily have 0.01 ohms of resistance depending on the wind count. If you apply 14.8v to that, the current would be 1,480A. Of course, your batteries, wiring, and/or ESC could only deliver this for a few uS before burning up.

Just curious, why do you want to know this?

	(#3)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	09.26.2008, 12:36 AM Finding the DC resistance would take some special equipment if it's not listed. This is the resistance of a stalled motor. And the inductive reactance will vary with frequency and rotor movement. The DC resistance will always be VERY low, but isn't really useful for general calculations. For instance, a motor could easily have 0.01 ohms of resistance depending on the wind count. If you apply 14.8v to that, the current would be 1,480A. Of course, your batteries, wiring, and/or ESC could only deliver this for a few uS before burning up. Just curious, why do you want to know this?