Electric Motor Control
10th Edition
ISBN: 9781133702818
Author: Herman
Publisher: CENGAGE L
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Textbook Question
Chapter 42, Problem 8SQ
Approximately how much time (in terms of electrical cycles) elapses from the moment the PFR opens to the moment the motor actually synchronizes?
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Students have asked these similar questions
2. How many poles does a synchronous motor have if it operates at 200 rpm when
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*A synchronous motor working at leading power factor can be used as
Synchronous induction motor
Static condenser
Synchronous condenser
None of the above
The speed regulation of a synchronous motor is
100%
50%
25%
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* The armature current of the synchronous motor has large values for
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Chapter 42 Solutions
Electric Motor Control
Ch. 42 - What are the two basic methods of automatically...Ch. 42 - What is an out-of-step relay?Ch. 42 - Why is an out-of-step relay used on automatic...Ch. 42 - Under what conditions will the out-of-step relay...Ch. 42 - What is the last control contact that closes on a...Ch. 42 - What influence do both of the polarized field...Ch. 42 - Prob. 7SQCh. 42 - Approximately how much time (in terms of...Ch. 42 - How does the AC coil of the PFR receive the...Ch. 42 - Why is a control relay (CR1) used in Figure 426?...
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, electrical-engineering and related others by exploring similar questions and additional content below.Similar questions
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- What kind of current does a synchronous motor with an excessively increased excitation current draw from the network? a) apparent current b) capacitive current c) inductive current d) ohmic currentarrow_forwardQarrow_forwardThe rotor of the 4-pole three-phase squirrel cage induction motor has been replaced with the rotor of the three-phase 4-pole rotor wound induction motor. When the motor is fed with normal supply, the machine will a) Does not work b) Runs at a very slow pace c) Runs at slightly lower speed than normal speed d) Runs at a slightly higher speed than normal speed e) nonearrow_forward
- Q15. A synchronous machine is connected to power grid. When its operating mode changes from generator mode to motor mode, what change will happen to electromagnetic toque? Give your explanation.arrow_forwardDefine or state the principle of operation, draw the wiring diagram, discuss the construction and application of each motor Split phase capacitor motor Repulsion motorarrow_forwardSuppose a stepper motor with a 12-degree step angle has 752 pulses applied to it per second. What is its rotating speed in rpms?arrow_forward
- How are a PSC motor and a capacitor-start-capacitor-run motor similar? Select one: A. BOTH USE A STARTING CAPACITOR B. BOTH USE A RUNNING CAPACITOR C. BOTH USE STARTING RELAYS D. NONE OF THE ABOVEarrow_forward5. How Can You Reverse The Direction Of Rotation Of A D.c Motor?arrow_forwardINDUSTRIAL ELECTRONICS 2arrow_forward
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