Deck 2: Manual Starters and Overload Relays

Question 1

Overloads are designed to protect the circuit from a short-circuit condition.

Answer 1

False

Question 2

Three-phase motors must have an overload sensor (heaters or magnetic coils) in two of the three-phase lines.

Answer 2

False

Question 3

There are two major types of overload relays: thermal and ____.

A) circuit
B) metallic
C) magnetic
D) electric

Answer 3

magnetic

Question 4

Electronic overload relays employ a current ____ to sense the motor current.

A) diode
B) transformer
C) capacitor
D) varistor

Question 5

All overload relays contain a set of normally ____________________ contacts.

Question 6

What determines the amount of warp in a bimetal strip overload relay?

Question 7

How can you protect large horsepower motors?

Question 8

Manual starters are characterized by the fact that the operator must go to the location of the starter to initiate any change of action.

Question 9

Anytime a motor has tripped on overload, the electrician should check the motor and circuit to determine why the overload tripped. The first step is generally to ____.

A) determine if the motor is actually overloaded
B) put the motor back into operation
C) lower the air temperature
D) replace the insulation

Question 10

When using a sensing pilot device to directly control the operation of a motor, you must make sure that the type of pilot device is equipped with contacts that can handle the rated current of the motor. These devices are generally referred to as "____________________" devices.

Question 11

Manual starters that are installed in a(n) ____________________ inside a wall are especially susceptible to ambient temperature problems.

Question 12

What enclosures are available for fractional horsepower starters?

Question 13

Discuss the differences between two- and three-load contact manual push-button starters.