Understanding Motor Controls
3rd Edition
ISBN: 9781305498129
Author: Stephen L. Herman
Publisher: Cengage Learning
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Chapter 9, Problem 1RQ
To determine
Identify how the direction of rotation of a three-phase motor can be changed.
Expert Solution & Answer
Explanation of Solution
By changing any of the two motor leads, the direction of rotation of any three-phase motor can be reversed. Separate contactor will be required in each direction since the motor is connected to the power line regardless of the operating direction.
As per NEMA standards, the leads 1 and 3 will be changed for reversing and only one overload relay is needed to protect the motor. A reversing controller is one in which two separate contactors and one overload relay are built as one unit.
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A start-up company wants to convert an ICE vehicle into an electric vehicle with the following specification.
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