Electric Motor Control
10th Edition
ISBN: 9781133702818
Author: Herman
Publisher: CENGAGE L
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Question
Chapter 33, Problem 1SQ
To determine
Explain the reason for the idle winding to remain open circuited in the running condition of a four speed, two winding motor.
Expert Solution & Answer
Explanation of Solution
Refer to Figure 33-2 in the Textbook, which illustrates the common motor connections of the four-speed, two winding motors with different speeds.
The idle winding of the motor remains to be open circuited in running state on given speeds. Through open circuiting, energizing windings can be prevented from imposing of unnecessary electrical loads. These loads can result from the transformer action which produces the circulating currents in the secondary, idle winding.
Conclusion:
Thus, the reason for the idle winding to remain open circuited in the running condition of a four speed, two winding motor is explained.
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Chapter 33 Solutions
Electric Motor Control
Ch. 33 - Prob. 1SQCh. 33 - Prob. 2SQCh. 33 - Prob. 3SQCh. 33 - What is the primary reason for using a compelling...Ch. 33 - What is the purpose of an accelerating relay?Ch. 33 - When is it most important to use decelerating...Ch. 33 - Why are different motor connections shown for what...Ch. 33 - How many windings are required for three-speed...
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