Electric Motor Control
10th Edition
ISBN: 9781305177611
Author: Herman
Publisher: Cengage
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Textbook Question
Chapter 3, Problem 27SQ
Select the best answer for each of the following.
If an operator pushes a start button on a three-phase induction motor and the motor starts to hum, but not run, the probable trouble is
- a. one fuse is blown and the motor is single phasing.
- b. the overload trip needs resetting.
- c. the auxiliary contact is shorted.
- d. one phase is grounded.
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Students have asked these similar questions
Find Vo using mesh analysis
c)
An RC circuit is given in Figure Q1.1, where Vi(t) and Vo(t) are the input and
output voltages.
(i) Derive the transfer function of the circuit.
(ii) With a unit step change of Vi(t) applied to the circuit, derive the time
response of Vo(t) with this step change.
Vi(t)
C₁
Vo(1)
R₂ C2 C3 |
R = 20 ΚΩ = 50 ΚΩ
C=C2=C3=25 μF
Figure Q1.1. RC circuit.
c) An RC circuit is given in Figure Q1. vi(t) and vo (t) are the input and output
voltages.
(i) Derive the transfer function of the circuit.
(ii) With a unit step change vi(t) applied to the circuit, derive and sketch the
time response of the circuit.
R₁ R2
v₁(t)
R3 C₁
v₁(t)
R₁ = R₂ = 10 k
R3
= 100 kn C₁ = 100 μF
Figure Q1. RC circuit.
Chapter 3 Solutions
Electric Motor Control
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