hi friend
how r u?

i want to know that what are main parameters that are responsible for duty or class of induction motor?
can any body help me?

thank you

 

Heat build-up/generated by an induction motor. Some wearing in long term can be considered as a factor.

 

There is no one sentence answer. Some of the principle requirements concerning "duty" are related to nominal or running torque, startup or acceleration torque, starts or reversals per hour, moments of inertia, driven-machine applications, available cooling methods, etc.

I suggest as a start, that you avail yourself of an Electrical Engineering Handbook such as Fink & Carroll's Standard Handbook for Electrical Engineers (USA) or the National Electrical Manufacturers Association (NEMA) standards (USA).

In addition a web search will reveal a myriad of USA, European, and Oriental references from motor manufacturers, motor-starter vendors, pump, compressor, and fan suppliers.

 

Often called "inverter duty" motor because it is PWM inverter operation that creates motor problems - motor winding insulation stress and additional motor PWM iron loss.

For short machine PWM loss introduction see PWM loss article overview at

http://www.drbrushless.com/cgi-bin/articles.phtml

-Yuri