Motors ch-8

Question 0

2.Assume that the overload contact is connected in parallel with the starter coil.what happens when the starter button is pressed?

Answer 0

The control fuse will probably blow

Question 1

1.When a control component is connected in a circuit to perform the function of stop?

Answer 1

It is connected in series with the starting coil.

Question 2

3.How is the amount of overload current set for a particular motor?

Answer 2

By changing the size of the overload heater.

Question 3

4.When a control component is connected in the circuit to perform the function of Start?

Answer 3

It is connected in parallel with the start button.

Question 4

5.To determine if the start pushbutton is good or bad with an ohmmeter continuity should be indicated when?

Answer 4

The button is pressed yes

The button is no pressed no

Question 5

6.The coil of a motor starter has a resistance of 6 ohms but current flow of 0.1 a with 120 VAC applied. Is this normal and why?

Answer 5

Yes current is limited by inductive reactance not resistance.

Question 6

7.Assume that the two stop push buttons are connected in parallel instead of in series.what is the action of this circuit?

Answer 6

Both stop buttons have to be pressed to de-energize the circuit

Question 7

8.A stop push button?

Answer 7

Can be double-acting pushbutton with only normally closed section used.

Question 8

9.assume that the two start pushbutton

Are connected in series instead of parallel.what is the action of the circuit?

Answer 8

Both start buttons have to be pressed to energize the starter coil.

Question 9

10.when the start buttons 1 & 2 are pressed the motor does not start. Which of the following can cause this problem?

Answer 9

The overload contact is open

Question 10

11.When start buttons 1&2 are pressed the starter energizes by t he motor does not run. Which of the following can cause this condition?

Answer 10

The motor stator winding is open

Question 11

12. Assume that the motor is operating. When the stop button 1 is pressed the motor continues to run. When the stop button 2 is pressed the motor stops running. Which of the following can cause this condition?

Answer 11

stop button 1 is shorted

Question 12

13.When start button 2 is pressed the starter does no energize. When start button 1 is pressed the circuit does energize. Which of the following can cause this problem

Answer 12

The contact of start button 2 are not making connection when the button is pressed.

Question 13

14.A voltmeter connected across start button 1 indicates 120v when the button is pressed. When the meter is connected across start button 2 it indicates 0v when pressed.what does this test reveal?

Answer 13

Start button 1 is defective

Question 14

15.When either of the stop buttons are pressed the motor continues to operate normally. A voltmeter connected across either stop button indicates 120v when the button is pressed. What does this test indicate?

Answer 14

The load contacts are welded shunt.

Question 15

16.Assume that the stop pushbutton 2 is incorrectly connected normally open. What is the action of the circuit?

Answer 15

The circuit can operate If stop button 2 is held down.

Question 16

17.Assume that start button 1 was incorrectly connected normally close. What will be the action of the circuit?

Answer 16

The motor will start running as soon as power is applied to the circuit

Question 17

18. Assume that the normally open auxiliary contact is incorrectly connected in series with the stop button instead of in parallel with start buttons. What is the action of the circuit?

Answer 17

The circuit will not energize when either of the start button is pressed.

Question 18

19. The motor begins running when power is applied. If either stop button is pressed the motor stops. When the button is release the motor restarts.what can not cause this problem?

Answer 18

The over load contact is open

Question 19

20.A voltmeter connected across the overload contact indicates full line voltage when start button 1 is pressed.the voltmeter indicates 0v when the start button is release. What does this test indicates?

Answer 19

The overload contact is open