Motors

The field coils of a series motor are connected in series with the _______________________________.

• windings

• armature

• coil

• capacitor

A(n) ____________________ is used to provide the switching action required for continuous DC motor

rotation.

• coil

• capacitor

• 3 way

• comutator

The most common class of insulation used in motor manufacturing and rewinding is NEMA

____________________.

• class C

• class A

• class B

• class D

All motors with a voltage rating greater than ____________________ must have a thermal protector.

• 240 v

• 600 v

• 480 v

• 277 v

What type of motor requires brushes, slip rings, and an amortisseur winding? __________________

____________________

• brush less motor

• open motor

• enclosed motor

• A synchronous motor

The two basic types of DC motor connections are the __________________ and __________________.

• open and close

• series motor and shunt motor

• shunt and closed

• shunt motor and closed motor

Explain slip and why it is present. _________________________________________________________

________________________________________________________________________________________

________________________________________________________________________________________

________________________________________________________________________________________

________________________________________________________________________________________

________________________________________________________________________________________

________________________________________________________________________________________

• The rotor speed is such that sufficient torque

  is produced to balance the restraining torque

  caused by motor friction and mechanical load.

• The difference between the synchronous speed

  and the rotor speed is known as slip.

• none of the above

• In an induction motor, the rotor always rotates

  at a speed less than the synchronous speed.

  The rotor speed is such that sufficient torque

  is produced to balance the restraining torque

  caused by motor friction and mechanical load.

  The difference between the synchronous speed

  and the rotor speed is known as slip.

Most industrial motors are NEMA Design ____________________.

• A

• B

• D

• F

What type of rotor is most commonly used in an induction motor? ______________________________

________________________________________________________________________________________

• Closed rotor

• Locked rotor

• A squirrel cage rotor

• Open rotor

An insulation resistance test can be used to determine ____________________.

• hp rating of a motor

• FLA rating of a motor

• motor dampness

• field strength of a motor