Electric Motors


I need to know about the efficiency of 3 phase electric motor where i have only input voltage,current,frequency & rpm.

What is the formula to find the efficiency?

asked 12/14/2016

3 Answers

an electric motor is an electrical machine thats convert electrical energy to mechanical energy most electric motors  operate through the interaction between the motors magnetic field and winding currents to generate force in the form of rotation
answered 2/8/2019 rajkishor 2

Po(power out)
Pi(power in)

thus, if you have the rating of the power delivered you just divide it and get your efficiency 

OR can use the following 

E=(746*HP)/[(746*HP)+(watts lost)] Where 746 is a constant and HP=horsepower

just my two humble cents, hope this helps

answered 9/21/2018 Expeditions Conquistador 2
Expeditions Conquistador
i think by using the relation of the losses so we can find the losses and subtract the losses we get output .
i think it is correct .we can get an appropriate efficiency. if wrong forgive me sir .
and please tell me the solution sir.
thank you
answered 12/30/2016 Thulasi 2

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