Electric motor principle is convert the energy from electrical to mechanical process.The mechanical process is a load such as pump,blower,grinding and etc.Energy will lost from this process.

We can determine the efficiency of a electric motor by intrinsic losses.To reduced it we only can changes in motor design and operating condition. From lab test,a losses can vary from 2% to 20 %.

The simple definition of efficiency motor is “the ratio of a motor’s useful power output to its total power output.”
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