Understanding Motor Controls
3rd Edition
ISBN: 9781305498129
Author: Stephen L. Herman
Publisher: Cengage Learning
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Textbook Question
Chapter 30, Problem 1RQ
Name three methods of braking a motor.
Expert Solution & Answer
To determine
Identify three methods of braking a motor.
Explanation of Solution
The motors are generally slowed to stop by disconnecting thee power supplied. But, there are instances where that is not convenient. In these instances, brakes are applied to the motor to slow or stop the motor.
Some of the methods of braking a motor are:
- Mechanical brakes.
- Dynamic brakes.
- Plugging.
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2: A rectangular aluminum block is loaded uniformly in three directions. The loadings are as follows:a 50 kN total resulting compressive load in the x-direction, a 200 kPa uniformly distributed tensile load in they-direction, and a 0.03 MN total resulting tensile load in the z-direction. The block has the following dimensions:L = 1 m, b = 20 cm, h = 350 mm. Use E = 70 GPa and ν = 0.25.Determine the strain in the x and y axes respectively. For the strain in the y-direction to be equal to 0, how much uniformly distributed load inthe surface of y-direction should be added? (+ for tensile, - for compressive)
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5 -1.122 x10-5 / 3 decimals
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Chapter 30 Solutions
Understanding Motor Controls
Ch. 30 - Name three methods of braking a motor.Ch. 30 - How is the braking force of drum type brakes...Ch. 30 - Why are mechanical brakes often used on cranes?
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