Motor Efficiency Classification Curve

Motor Efficiency – IEC Standards & Classification

Motor Efficiency – Standards and Classification per IEC60034

New IEC 60034-30-1 defines four motor efficiency levels for three-phase induction motors. The updated standard IEC 60034-30-1 includes IE1, IE2, IE3, IE4 and the latest in-addition is IE5. 8-pole motors and extended power range added to standard.

Efficiency classes

IEC 60034-30-1 defines efficiency classes for induction motors (IE):

  • IE1 (Standard Efficiency)
  • IE2 (High Efficiency)
  • IE3 (Premium Efficiency)
  • IE4 (Super Premium Efficiency)
IEC Standard includes the following line-motors
Number of poles2, 4, 6, 8
Power range0,12 – 1.000 kW
LevelIE1 – Standard Efficiency
IE2 – High Efficiency
IE3 – Premium Efficiency
IE4 – Super Premium Efficiency
Voltage< 1000 V, 50/60 Hz
Degree of protectionall
Operating modeS1 (permanent operation with constant load); motors, that are designed for different operating modes but can still be operated permanently with rated output.
Degree of temperature-20°C – +60°C
AltitudeUp to 4.000 m above sea level
Geared motorsyes
Smoke Extraction Motors with a temperature class up to 400°Cyes
ValidityStandard IEC 60034-30-1 valid since  March 2014

For Example:

  • A 4 pole small motor of 2 hp operating at 50 Hz:
    IE1 efficiency is 77.2%
    IE2 efficiency is 82.8%
    IE3 efficiency is 85.3%
  • For bigger ones, 2 pole 200 kW operating at 50 Hz:
    IE2 efficiency is 95.3%
    IE3 efficiency is 95.8%

We offer axial fans, Jet fans, centrifugal fans with IE2, IE3 and IE4 motors.

Payback period will depend upon the running hours and cost of electricity. Energy represents more than 97 percent of total motor operating costs over the motor’s lifetime.

The payback period is determined by dividing the initial cost of energy-efficient equipment by projected annual savings.

If a Motor Costs INR30,000 and the estimated savings is something around 1KW everyday, the cost is INR 1 for every hour of power consumption , the total projected annual savings would be INR 7300.

Now, 30,000/7300= approximately 4 years, which is your payback period.

Note: All figures used are imaginary and for illustration only

Motor Efficiency Classification Curve