Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Calculating Motor curve

  1. Aug 29, 2016 #1
    Hi there,

    I have a motor peak torque, peak power, peak speed, rated torque, rated power, rated speed, torque at max speed.

    I was able to produce the peak torque curve.
    But, i don't understand how to create this continuous torque curve here. I have attach a link here, and somehow the continuous torque starts curving before the rated speed?

    I thought, the torque for the "continuous torque curve" should remain constant up to the rated speed then only start curving? I seen a lot of motor does the same. What formula should i use to calculate this curve/

    Power = 2*3.142*torque * speed


    Last edited by a moderator: Aug 30, 2016
  2. jcsd
  3. Aug 30, 2016 #2


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    Norton blocks my access to that page but..

    Not all motors are rated for continuous use. Many are rated for intermittent use. In other words they might be able to deliver the rated power at the rated speed intermittently but not continuously. If you try to use them at max load continuously they may overheat.
  4. Aug 30, 2016 #3
    yup, i understand the concept.
    I'm just wondering how to plot the continuous torque curve.
  5. Aug 30, 2016 #4


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    I'm not sure it can be calculated easily. If you were the motor manufacturer you would have access to its thermal properties. That would allow you to work out how much power the motor can be allowed to dissipate as heat. That and data on the efficiency of the motor would tell you how much power and torque the motor can be allowed to deliver continuously at any given speed.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted