How Can A High-Torque Motor Have Low a low RPM

012anonymousx

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.

Simon Bridge

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.

rcgldr

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

russ_watters

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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012anonymousx	How Can A High-Torque Motor Have Low a low RPM 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.

Simon Bridge Recognitions: Homework Help	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.

rcgldr Recognitions: Homework Help	The increase in torque at lower rpm is offset by increase in back emf at higher rpm, which decreases the torque at higher rpm.

russ_watters Mentor	How Can A High-Torque 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.