Exam 13: Motors and Drives

A servo drive is the least complex type of variable frequency drive system available.

A(n) ____________________ motor is wound like an AC induction motor, but it uses permanent magnets on the rotor and does not contain a commutator.

____________________ is used to control the speed of DC motors above the base speed.

A DC motor will generally require more maintenance than an AC motor.

Motors operate based on the principle of ____________________.

The principal parts of an electric motor include the stationary frame, or stator and the revolving part, or ____.

The difference between synchronous speed and actual rotor or motor speed is referred to as slip and is normally expressed as a percent of synchronous speed.

In a variable frequency drive, the ____________________ circuit converts incoming AC power to DC.

Application of ____ motors should be avoided for light loads or loads that are not directly coupled.

The repelling forces between the magnetic field generated around the wires and the magnetic field produced by the stator poles will generate a force that causes the armature to rotate. This rotating effect created by the interaction between the magnetic fields results in ____.