combination worm gearbox has the most commonly used drive

combination worm gearbox has become the most commonly used drive controller because worm gear reducer works well with motors ranging in size from about 1/2 hp to 500 hp. A significant reason for its popularity is that it's highly reliable, affordable and reflects the least amount of harmonics back into its power source. Most units are rated either 230V or 460V, 3-phase, and provide output frequencies from about 2 Hz to 400 Hz. Nearly 100 manufacturers market the PWM controller.