WHAT IS EFFICIENCY?
Energy requirement is increasing day by day in the world. It has become very difficult to meet the increasing energy demand with limited resources. Accordingly, countries develop activities in order to produce their own energy and to use the energy resources they have. For this reeason, while the need for energy is increasing, the usage of efficient products that consume less energy has become more and more important. The birth of efficiency classes in electric motors is also based on this point.
The efficiency classes developed in 2008 according to the IEC (International Electrotechnical Committee) 60034-30: 2008 standard has come up to the present day. These classes are IE1, IE2, IE3 and IE4 as shown in the graph below. Although the most efficient class is IE4, the least efficient class is IE1.
Class IE1 = Standard Motors
Class IE2 = High Efficiency Motors
Class IE3 = Premium Efficient Motors
Class IE4 = Super Premium Efficient Motors
Losses in electric motors; They consist of stator and rotor winding losses, iron losses, friction and cooling losses, and they are completely converted into heat. It is not enough to use only a high efficiency electric motor for the efficiency of a system but also to select an electric motor of suitable power and to run the motor in the highest efficiency zone. Electric motors are designed to provide the highest efficiency at nominal power. Therefore, the use of an electric motor larger or smaller than the required power causes the motor to work inefficiently. For this reason, should pay attention to the correct selection of the motor and the correct use of the motor.
As the efficiency of electric motors increases, the cost of the motor and therefore the price increases as the material used increases or the cost of the more used material increases. If the investment cost is not considered, the highest efficiency motor should always be preferred. However, if the investment is considered to pay for itself, which is the right way, then the unit price of electrical energy and the efficiency advantage of the efficient motor should be taken into consideration, how many hours a day the electric motor will work, how many days a year it will work. Although the investment seems to be high in the first place, considering that the average service life of an electric motor is 10 - 15 years, it will pay for itself in a short time and will provide a large cost profit in long term.