Today it can be said without exaggeration that about 90% of all motors manufactured are the singlephase type. They are used extensively in homes, businesses, farms, and small industries. Most of them are built as fractional-horsepower (hp) or subfractional-horsepower motors (1 hp is equal to 746 W). Standard ratings for fractional-horsepower motors range from 1/20 to 1 hp. The small motors rated for less than 1/20 hp, called subfractional-horsepower motors, are rated in millihorsepower (mhp) and range from 1 to 35 mhp.