
Is your motor taking a toll on your pocket?

1. What is the Application?
It has been found that the same IE4 or IE 5 motor retrofits have resulted in additional savings with changing applications. For example, in SEE Tech’s Energy Efficient Motors Implementation program, the savings arrived with the same IE5 motor (1.5 KW, 3000 RPM), all other conditions remained the same, savings achieved in a pump application has been 25%, agitator application 29% and for elevator application 39%. However, it must not be assumed that a pump application gives the least and an elevator application gives the highest savings. These numbers are applicable just for those machines. But, yes, it can be interpreted that savings through IE5 motors are significantly higher.
2. Nameplate or Full load Motor Efficiency: What does it convey and doesn’t?

2. Nameplate or Full load Motor Efficiency: What does it convey and doesn’t?
As seen in the above graph, motor efficiency drops with underloading of the motors (more in IE1 & lesser in IE5); this implies that for the same load if a higher size motor is installed, it will draw more power. In the field also, the same has been observed. Interestingly, on a load drawing 4.1 KW on an IE2 class 7.5 KW motor (88.7% efficiency), an IE2 class 5.5 kW motor (87.7% efficiency) was installed, and it was ensured that the motor RPM and the load remained the same, the input power reduced to 3.94 KW. The reason was that loading improved from 48.52% to 62.83%, causing operating efficiency to improve from 83.41% to 86.51% (The loading & efficiency numbers are obtained by using SEE-Tech’s software: (SEE-UtiSave).
4. IE1 to IE5 Motor Efficiency at Various Loading – how much flatter is the curve?

5. Motor & load connection (Direct/Belt/Gear): How does this impact?
6. The difference between Motor Nameplate & Synchronous RPM
7. Opportunity to enhance savings through automation
So, to conclude, all seven aspects collectively play an important role in getting the best possible savings, and that’s why all the seven aspects must be considered simultaneously for the selection of the motor. It’s not about just getting the savings by moving from IE1 to IE5; it’s about getting the maximum outcome from the investments made.
