INDUSTRIAL MOTOR CONTROL
7th Edition
ISBN: 9780357670590
Author: Herman
Publisher: CENGAGE L
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Question
Chapter 29, Problem 1RQ
To determine
The way in which the direction of the rotation of the three phase motor can be changed.
Expert Solution & Answer
Explanation of Solution
The direction of the rotation of three phase motor is changed by changing the leads connection. Consider the Figure 29-1 of the text book as it has T leads, when the leads 1 and 3 are interchanged then the motor starts to rotate in the opposite direction.
The change in terminals changes the flow of current and it changes the direction of the rotation of the field thus, it changes the direction of rotation of the motor.
The rotation of the motor is also changed by the help of the reverse starter as shown in Figure 29-2 in the text book.
Thus, the direction of the rotation of the three phase is obtained by the change inn terminals.
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