Motor Torque - Power vs RPM Explained

[stan]

hi

does anyone knows what exactly is a motor's nominal torque.

for example, if i have a variable speed motor that runs from 0 to 3000rpm and its rated power is 3hp, then are there various nominal torque for different rpms?

then which should i choose to if i need to connect it to a reducer?
thanks for any help.


stan

 

[FredGarvin]

The rated torque should be given at a specified RPM or the rated power should be given at a specified RPM to calculate the available torque. The torque will definitely vary as the speed changes. You need to get a torque curve for the motor to know exactly what you have to deal with. The vendor of the the motor will be able to provide that if you ask for it.

 

[ravenprp]

Hi Stan,

Nominal torque refers to the maximum amount of torque that a motor can consistently produce at its rated power. In your example, the nominal torque for your motor would be the maximum amount of torque it can produce at 3hp, which would be at its rated speed of 3000rpm. However, this does not mean that the motor cannot produce torque at other speeds. As the motor's speed decreases, its torque output will increase, up to a certain point. This is known as the motor's torque-speed curve.

When selecting a motor to connect to a reducer, it is important to consider both the motor's nominal torque and its torque-speed curve. The reducer will decrease the motor's speed and increase its torque, so you will need to make sure that the motor can still produce enough torque at the reduced speed to meet your application's requirements.

I hope this helps clarify the concept of nominal torque and its relationship to motor speed and power. Let me know if you have any other questions.