Deck 10: Components for Electric Motors

Question 1

The two types of bearings used in the heating, cooling, and refrigeration industry are ____________________ bearings and sleeve bearings.

Answer 1

ball

Question 2

What should be done for a permanent split-capacitor hermetic motor that is experiencing difficulty starting?

Answer 2

On many permanent split-capacitor hermetic motors that are experiencing difficulty starting, a hard-starting kit can be installed to eliminate the problem, making the PSC motor a capacitor-start-capacitor-run motor.

Question 3

A(n) ____________________ is that part of a rotating electric device that allows free movement.

Answer 3

bearing

Question 4

The advancement of solid-state controls has produced another type of current-sensitive relay, a PTC starting switch.

Question 5

The ____________________ is gaining popularity because it can be adapted easily to most any compressor.

Question 6

On all electric motors, the starting amperage is less than the running amperage because the rotor is stationary on startup.

Question 7

In an open-type motor, dropping the starting winding out of the circuit is accomplished by a centrifugal switch mounted on the motor that opens once the motor has reached 35% of its full speed.

Question 8

____________________ methods require that a device turn with the same revolutions per minute as the motor.

Question 9

The running amperage of an electric motor is usually stated as the full-load amperage.

Question 10

The back electromotive force is the amount of voltage produced in the starting winding of a motor.

Question 11

Single-phase motors, with the exception of the permanent split-capacitor motor, must have some means of dropping the starting winding out of the circuit.

Question 12

The back electromotive force produced by the starting winding of a motor is not the controlling factor of a potential relay.

Question 13

Ball bearings are designed with an inner and an outer ring, which enclose the balls by use of a(n) ____________________.

Question 14

What are the two basic types of motor drives used today?

Question 15

The potential relay is easy to troubleshoot because only two parts of the relay must be checked.

Question 16

What are the three types of starting relays used on single-phase hermetic motors ?

Question 17

Describe the three ways in which ball bearings are lubricated and how often each should be done.

Question 18

By using two pulleys and connecting them with a(n) ____________________, rotation can be transferred from the motor to the device.

Question 19

The starting amperage of an electric motor is usually stated as the ____________________.

Question 20

The current relay is built much like a solenoid, with copper wire wrapped around a steel hollow core holding a steel plunger.