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Motor Parameters?


#1

Hi, iam using 131:1 Metal Gearmotor 37Dx73L mm with 64 CPR Encoder, the motor parameter are given ,i want to find the physical parameters, could you please check the Validity
The electrical resistance of the motor can be approximated by dividing the rated voltage by the stall current
R=5A/12=2.4;
The electromotive force constant (Ke) can be approximated by dividing the rated voltage by the free-run speed (at the rated voltage).
Here 80 RPM(8.3775rad/s) which is the shaft speed, so before the gearbox 8.3775*131.25=1099.58rad/s
Ke=1099.58/12=0.010911;
To approximate the motor torque constant (Kt), you can divide the stall torque by the stall current. Here maximum torque can be taken as 1.765(NM stall torque)/131.25=0.01345Nm
Kt=0.01345Nm/5A=0.002689
Thanks


#2

Hello,

From your calculations it looks like you are trying to figure out the motor parameters without the gearbox. If that is what you are trying to do, you will probably get better results using the specifications for the replacement motor without gearbox we carry.

Please note your division is show in the wrong order, but otherwise your calculations seem fine.

-Derrill