Small Electric Motors
A small electric motor is a fractional horsepower motor that has less than one horsepower, or 745.7 watts, of power. Small electric motors consist of several basic parts: an axle, a metal enclosure, a field magnet, a nylon end cap, a rotor, a coil, and two battery leads. The motor spins in different directions based on how the battery leads are hooked up.
Like all electric motors, small electric motors convert electrical energy into mechanical energy. Electric motors change electric energy into rotational movement by using the natural behavior of magnetism. Magnetic polarity, the attracting and repelling forces of a magnet, causes rotation.
Small electric motors are used in a wide variety of applications in almost every industry because they are cleaner and less expensive to run than fuel-powered motors. They are used in welding, small centrifuge devices, pitching machines, wheel chairs, door openers, pumps, and frozen yogurt machines.
In some cases, motors can still be classified as fractional horsepower motors even if the horsepower exceeds one unit. This exception is based on the frame size standards set by NEMA, the National Electrical Manufacturers Association. If the frame size of the motor is a 42, 48, or 56, the one horsepower guideline does not apply.