Motors

Question 1

What is a movable electromagnet located between the poles of another fixed permanent magnet?

Answer 1

Armature

Question 2

What is a conducting, segmented ring that provides the action of reversing current direction in an armature?

Answer 2

Commutator

Question 3

This provides a connection between the movable commutator and the stationary DC power source.

Answer 3

Brush

Question 4

What is a Shunt Motor and what are its advantages and disadvantages?

Answer 4

A DC motor with the shunt field connected in parallel with the armature. It has a more constant speed as it only changes a few rpm when the load changes but it does not develop much torque at the start.

Question 5

What is a Series Motor and what are its advantages and disadvantages?

Answer 5

A DC motor with the shunt field connected in series with the armature. It has a much higher full load torque at start (500%) but less speed control as it may reach dangerous speeds and self-destruct when the mechanical load is removed entirely.

Question 6

When a series winding is connected to aid the shunt winding it is called…

Answer 6

a cumulative compound motor.

Question 7

When a series winding opposes a shunt winding it is called…

Answer 7

a differential compound motor.

Question 8

What are the 2 types of brushless DC motors?

Answer 8

The inverter-induction motor and one with an electronic commutator.