Motor Standards: the International Electrotechnical Commission (IEC)
As we know, various standards exist which specify various operating and constructional parameters of a motor. The International Electrotechnical Commission (IEC) is one main standard in the world.
The International Electrotechnical Commission (IEC) is a European-based organization that publishes and promotes worldwide, the mechanical and electrical standards for motors. It's the international counterpart of the National Electrical Manufacturers Association (NEMA).
We have introduced 5 design types of the National Electrical Manufacturers Association (NEMA) in our previous articles. Below we explain the motor standard: the International Electrotechnical Commission (IEC).
The International Electrotechnical Commission (IEC) Torque-Speed Design Ratings practically mirror those of NEMA. The IEC Design N motors are similar to the National Electrical Manufacturers Association (NEMA) Design B motors, the most common motors for industrial applications. The International Electrotechnical Commission (IEC) Design H motors are nearly identical to NEMA Design C motors.
The IEC Duty Cycle Ratings are different from those of the National Electrical Manufacturers Association (NEMA)'s. Where NEMA usually specifies continuous, intermittent or special duty (typically expressed in minutes), the International Electrotechnical Commission (IEC) uses nine different duty cycle designations (IEC 34-1).
The standards, shown in the table below, apart from specifying motor operating parameters and duty cycles, also specify temperature rise (insulation class), frame size (physical dimension of the motor), enclosure type, service factor and so on.
motor duty cycle types as per International Electrotechnical Commission (IEC) standards:
