Electric Motor
An electric motor converts electrical energy into mechanical rotation through the interaction of magnetic fields. The three-phase squirrel-cage induction motor is the most widely used industrial type; others include permanent-magnet synchronous, wound-rotor and DC motors. Motors drive pumps, fans, compressors, conveyors and mixers. Key selection parameters are rated power (kW), voltage, frequency, speed (number of poles), frame size, mounting arrangement, enclosure protection (IP code per IEC 60034-5), cooling method, insulation class, duty type and starting method. International efficiency (IE) classes are defined in IEC 60034-30-1, and frame dimensions follow IEC 60072. Motors for hazardous areas carry an Ex protection type such as Ex d, Ex e or Ex ec under the IEC 60079 series, with ATEX or IECEx certification.
Examples
- IE3 TEFC motor driving a centrifugal pump
- Ex d motor for a compressor in a Zone 1 area
- Permanent-magnet motor on a variable-speed fan