
#1
Jan913, 09:01 PM

P: 47

Torque is the rotational force.
If there is more force, how can the motor be slow? I'm building a DC motor and read that given a constant amount of coil, creating a very dense coil will increase torque but lower RPMs. Conversely, making it looser (bigger radius) increases RPM but lowers torque. 



#2
Jan913, 10:07 PM

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P: 10,925

The torque gives you acceleration  but it is possible to accelerate to any speed... however slow.
For your motor  it will accelerate to a constant speed due to losses that are proportional to speed. This will be proportional to the amount of mass that has to be spun  and so is the torque. 



#3
Jan913, 11:41 PM

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P: 6,925

The increase in torque at lower rpm is offset by increase in back emf at higher rpm, which decreases the torque at higher rpm.




#4
Jan1013, 05:23 AM

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P: 21,998

How Can A HighTorque Motor Have Low a low RPM
Motors are connected to loads. The load determines the ratio between RPM and torque. If a "high torque" motor is not connected to a load and is just allowed to freewheel, it does not produce any torque.



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