Because of its relatively low cost, simple and rugged construction, minimal maintenance requirements, and good operating characteristics that satisfy a wide variety of loads, the induction motor is the most commonly used type of ac motor. Induction motors range in size from a few watts to about 40,000 hp. Small fractional-horsepower motors are usually single phase and are used extensively for domestic appliances, such as refrigerators, washers, dryers, and blenders.