Advanced Electricity Final Review

When referring to motors, to what does the "insulation class" relate?

• the noise level of the motor

• the type of base on which the motor is mounted

• the normal operating temperature of the motor

• both a and b

A motor can burn out if the supply voltage is either too high or too low.

• True

• False

There is a definite relationship between the speed of the motor and the speed of the blower.

• True

• False

Regardless of the type of motor or application, the motor bearings require yearly lubrication.

• True

• False

The alignment of a motor and the driven mechanism must be done at room temperature and ____.

• after heating with the torch

• at operating temperature

• after running for one minute

• again after several days of operation

The alternating current frequency supplied by the power companies in the United States is ____________________ hertz.

• 60

• 50

• 25

• 0

One method a technician can employ to check a motor is to take amperage readings of a motor (both on start-up and after start-up) and compare them to the motor's nameplate.

• True

• False

A direct-drive motor is usually connected to a load with a ____.

• cradle mount

• rigid base mount

• pulley

• coupling

The motor that should be used in a potentially wet area is a(n) ____ motor.

• enclosed

• drip proof

• explosion proof

• open

If the applied voltage is too high, the motor may develop local hot spots within its windings, but it will not always experience  ____________________.

• high amperage

• low amperage

• high voltage

• low voltage