Such hoists change the power frequency through transducer and the lifting speed and the traveling speed to make the electric hoist travel more smoothly and more accurately. It has the following four features: 1. reduce starting and stopping impact, travel smoothly; 2. the lifting speed can be designed at random in the range of 1/8 rated speed; 3. to improve work efficiency, the lifting speed with no load can be set at random between the rated speed and 1.5 times the rated speed; 4. to change the frequency of the motor through transducer and make the motor work with slow speed in order to improve its site accurateness.
