Deck 37: Motor Installation

Question 1

Table 430.250 is used to determine the full load current of two phase motors.

Answer 1

False

Question 2

The National Electric Code  (NEC) tables list the amount of current that the motor is expected to draw under a full load condition.

Answer 2

True

Question 3

Starter sizes are rated by motor type, horsepower, and connected ____________________.

Answer 3

voltage

Question 4

What are the values which are used for determining the overload size for a motor?

Question 5

One of the factors that must be taken into consideration when determining the conductor size is the temperature rating of the devices and terminals.

Question 6

The temperature ratings of devices such as circuit breakers, fuses, and terminals are found in the ______________________________ product directories.

Question 7

What kind of single phase AC motors need to have their running current determined from the nameplate rating of the motor?

Question 8

How is the motor overload size determined?

Question 9

The current ratings for ____________________ phase AC motors are given in Table 430.248.

Question 10

When using a two phase, three-wire system, why must the size of the neutral conductor be increased by the square root of 2, or 1.41?

Question 11

Regardless of the temperature rating of the conductor, the ampacity must be selected from a column that does not exceed the ____________________ rating of the termination.

Question 12

The values listed in Table 430.248 are for motors that operate under high speeds and torques.

Question 13

How can the starting current of a squirrel cage induction motor be determined if the kVA, horsepower rating, and the applied voltage are known?

Question 14

Synchronous motors are often made to have a leading power factor by ____________________ of the rotor current.

Question 15

Most motor circuits are protected by dual-element time delay fuses or inverse time circuit breakers.