Understanding Motor Controls
4th Edition
ISBN: 9781337798686
Author: Stephen L. Herman
Publisher: Delmar Cengage Learning
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Textbook Question
Chapter 31, Problem 13RQ
Refer to the schematic diagram in Figure 31–8. Assume that the motor is not running. When the third speed push button is pressed, the motor starts in its lowest speed. After a delay of 3 seconds, the motor accelerates to second speed and 3 seconds later to third speed. After a period of about 1 minute, the fourth speed push button is pressed, but the motor does not accelerate to fourth speed. Which of the following could cause this problem?
- a. Control relay CR2 coil is open.
- b. S2 contactor coil is open.
- c. CR3 coil is shorted.
- d. S3 contactor coil is open.
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Chapter 31 Solutions
Understanding Motor Controls
Ch. 31 - Prob. 1RQCh. 31 - Prob. 2RQCh. 31 - A wound rotor induction motor has a stator that...Ch. 31 - Name three factors that determine the amount of...Ch. 31 - Prob. 5RQCh. 31 - Explain why controlling the rotor current also...Ch. 31 - What is the function of a micro limit switch when...Ch. 31 - Prob. 8RQCh. 31 - What is rotor slip?
Ch. 31 - Prob. 10RQ
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