Electric Motor Efficiency

Thursday, June 18, 2009

Interview Question: What is the Efficiency in Electric motor ?

 

Answer:

Power
(hp) Minimum Nominal Efficiency1)
1 - 4 78.8
5 - 9 84.0
10 - 19 85.5
20 - 49 88.5
50 - 99 90.2
100 - 124 91.7
> 125 92.4
as per NEMA


Electrical motor efficiency is the ratio between the shaft output power - and the electrical input power.Electrical Motor Efficiency when Shaft Output is measured in WattIf power output is measured in Watt (W), efficiency can be expressed as:m = Pout / Pin?



where



m = motor efficiency



Pout = shaft power out (Watt, W)



Pin = electric power in to the motor (Watt, W)



Electrical Motor Efficiency when Shaft Output is measured in Horsepower.

0 comments: