Electric Motor Control
10th Edition
ISBN: 9781133702818
Author: Herman
Publisher: CENGAGE L
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Textbook Question
Chapter 10, Problem 1SQ
Describe how pressure switches are connected to start and stop (a) small motors and (b) large motors.
(a)
Expert Solution
To determine
Explain how does the pressure switches are connected to start and stop small motors.
Answer to Problem 1SQ
The pressure switches are connected directly to start and stop small motors.
Explanation of Solution
Discussion:
In industrial applications, the pressure switches are used to sense pressure. A large variety of pressure switches are available to control the requirements of hydraulic machines or pneumatic machines.
Single-pole pressure switches are most commonly used and Two-pole pressure switches are used only for few applications.
In small motors, the pressure switches are directly connected to the load circuits when the capacities of the contact are sufficient for the load current.
Conclusion:
Thus, the pressure switches are connected directly to start and stop small motors.
(b)
Expert Solution
To determine
Explain how does the pressure switches are connected to start and stop large motors.
Answer to Problem 1SQ
The pressure switches are connected series with motor starter and line to start and stop large motors.
Explanation of Solution
Discussion:
In industrial applications, the pressure switches are used to sense pressure. A large variety of pressure switches are available to control the requirements of hydraulic machines or pneumatic machines.
Single-pole pressure switches are most commonly used and Two-pole pressure switches are used only for few applications.
In large motors, the pressure switches alone cannot handle the load circuits safely where it must be connected in series with the motor starter coil and line such that the starter can start and stop large motors safely.
Conclusion:
Thus, the pressure switches are connected in series with motor starter and a line are to start and stop large motors.
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Chapter 10 Solutions
Electric Motor Control
Ch. 10 - Describe how pressure switches are connected to...Ch. 10 - What type of pressure switch is generally used to...Ch. 10 - A pressure switch is set to cut in at a pressure...Ch. 10 - A pressure switch is to be installed on a system...Ch. 10 - A pressure switch is to be installed in a circuit...Ch. 10 - Refer to the circuit shown in Figure 105. If the...Ch. 10 - Refer to the circuit shown in Figure 105. Assume...Ch. 10 - Refer to the circuit shown in Figure 106. Assume...Ch. 10 - Refer to the circuit shown in Figure 106. Assume...Ch. 10 - Refer to Figure 106. When the thermostat contact...
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