Motor Constant

[KowdTek]

Can some help me how to measure motor constant?

[Brian_Beal]

Which constant are you referring to?  Torque, voltage, mechanical time, electrical time?

[Jochen]

If you are looking for a way to characterize the behaviour of your motor with LabVIEW, the LabVIEW system identification toolkit could be an interesting option for you.

Best regards,

Jochen Klier
National Instruments Germany

[KowdTek]

I want to measure the torque.

[Brian_Beal]

A rotary torque sensor would be the best bet.  Put the sensor between the motor and a load.  The output is just like a load cell.  You can also get them with built in encoders so you can measure speed directly.  You could then build a torque vs. speed curve.  Keep in mind that motors can put out more torque for a short amount of time, so I am not sure if you are looking for absolute torque capability or a continuous torque capability.  The continuous torque capability just depends on how much heat the motor can dissipate.

[Jochen]

The method for measuring the torque depends on the type of the motor. E. g. for a DC motor torque is proportional to the current that drives the motor so measuring the current is virtually the same as measuring the torque. For stepper motors it's not that easy as the current is driven through multpile coils and the general behavior is different. So for this type of motor a torque measurement device is recommended.
There are various types of torque sensors available (inductive torque sensors, eddy current torque sensors,...).

Jochen

[KowdTek]

Thank you very much guys I never thought I'll get this answer fast.

Just so let you know that I'm still new & learning LabView / M-Test.

Again, Thanks!