Modular induction motors to suit any application

These new ABB AMI series induction motors are engineered and constructed using a series of modular building blocks to provide a complete range of enclosures and cooling arrangements. This enables each AMI series motor to be delivered at a cost typical of off-the-shelf units, without compromising the suitability of the motor for each application or paying for unnecessary features. Available options include air-to-water and air-to-air cooling, as well as a weather-protected version. Protection classes range from IP24W to IP56.

The AMI series squeezes, says ABB, an extra 10% of power from each frame when compared to its predecessors, enabling users to opt for smaller, lighter motors to fit a given duty. This is an obvious advantage wherever space is tight. In addition, standard models keep noise levels below 82 dB(A), with some options reducing noise even further. This enables the motors to deliver a safer, more comfortable working environment for operators.

The basic framework of the new motors (IEC frames 560, 630 and 710) provides a proven platform, with new features developed using ABB's broad experience and a systematic process of design and review.

Design cuts vibration:

Low vibration has been a design priority for the AMI series. Less vibration reduces wear and tear, prolonging the life of the motor and surrounding equipment. A 2-pole stiff shaft rotor design is available for motors controlled by variable speed drives, which ensures that the motor can operate at any and all speeds within its 0 - 4000rpm range; because it's first critical speed (the speed at which a motor starts to resonate) is higher than the maximum running speed of the motor. In addition, low levels of vibration in the bearing housing enable AMI motors to meet the latest IEC and NEMA standards, as well as API and most similar specifications.

The motors have form wound windings with ABB's well-established Micadur Compact Industry Insulation System insulation class F (155oC). The Micadur system involves insulating the motor's windings and connections with Mica-based tape. With the windings in place, the whole stator is impregnated with a high-temperature varnish using a vacuum pressure impregnation process. This provides effective insulation that boosts the reliability and life of the motor.

The picture shows the new AMI series induction motors from ABB, ranging from 500 to 11,000kW.