Single-phase motors are not usually produced above 5 hp.

A three-phase generator can be driven by a single-phase motor.

Single-phase motors require some mechanism to produce a rotating field on startup.

However, the power rating needs to be at least 50% larger than for a comparable single-phase motor due to an unused winding.

Some types of single-phase motors can be used, but three-phase motors are usually preferred.

Description: Residential air conditioner units normally contain a single-phase motor driving a compressor.

Single-phase motors do not have a unique rotating magnetic field like multi-phase motors.

Like other single-phase motors, the Lavet motor is only able to turn in one direction, which depends on the geometry of its stator.

A single-phase motor can drive a three-phase generator, which will produce a high-quality three-phase source but with high cost for apparatus.

In certain smaller single-phase motors, starting is done by means of a shaded pole with a copper wire turn around part of the pole.

Three-phase motors also vibrate less and hence last longer than single-phase motors of the same power used under the same conditions.

Polyphase motors are simple to construct, are self-starting and have little vibration compared with single-phase motors.

The inverters are also great upgrade tools: replacing contactors for maintenance-free operation and allowing single-phase motors to be replaced with 3-phase versions.

To demonstrate how the cage rotor works, the stator of a single-phase motor and a copper pipe (as rotor) may be used.

The normal running windings within such a single-phase motor can cause the rotor to turn in either direction, so the starting circuit determines the operating direction.

Single-Phase Motor Starters"."

A common single-phase motor is the shaded-pole motor and is used in devices requiring low starting torque, such as electric fans, small pumps, or small household appliances.

Compared to single-phase motors and generators, polyphase motors are simpler, because they do not require external circuitry (using capacitors and inductors) to produce a starting torque.

In two-pole single-phase motors, the torque goes to zero at 100% slip (zero speed), so these require alterations to the stator such as shaded-poles to provide starting torque.

Wagner also held a patent on a self-starting, single-phase motor and founded in 1891 the Wagner Electric Manufacturing Company in St. Louis, Missouri.

In these cases, it is important to provide confirmation of the motor winding configuration, or at least the motor manufacturer's type reference, since there is a wide variety of single-phase motor types.

A single-phase supply connected to an alternating current electric motor does not produce a revolving magnetic field; single-phase motors need additional circuits for starting, and such motors are uncommon above 10 kW in rating.

Many single-phase motors having two windings can be viewed as two-phase motors, since a capacitor is used to generate a second power phase 90 from the single-phase supply and feeds it to the second motor winding.

A three-phase motor is more compact and less costly than a single-phase motor of the same voltage class and rating and single-phase AC motors above 10 HP (7.5 kW) are uncommon.

A 25 horsepower, Written-Pole single-phase motor was installed by Meridium Power Inc. in cooperation with Hitech Equipment, a local supplier of grain handling equipment and Friesen Electric, a local electrican.