... price is low; 4, level control, level difference is bigger, can't obtain smooth speed regulation; 5, can and regulating speed, electromagnetic slip ... scope, and can be used in the cage asynchronous motor;3, speed range is big, characteristic hard, high precision;4, the ... , speed rate is not more than 2.5 %,d our factory with precise control, speed rate less than 1 %Specification adjustable speed motor