Electric Motor Control
10th Edition
ISBN: 9781133702818
Author: Herman
Publisher: CENGAGE L
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Textbook Question
Chapter 42, Problem 10SQ
Why is a control relay (CR1) used in Figure 42–6?
FIG. 42–6 Line diagram for automatic operation of synchronous motor using polarized field frequency relay.
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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
- ٤arrow_forwardJ1. What are the standard identification letters for the shunt field winding of a DC compound motor? a) A1 and A2 b) S1 and S2 C) F1 and F2 d) none of the above J2. The commutating field is another term for interpoles. a) true b) false J3. What are the standard identification letters for the commutating field winding of a DC compound motor? a) C1 and C2 b) S3 and S4 c) either "a" or "b" d) neither "a" nor "b"arrow_forward1. Explain the working Principle of Single Phase Induction Motor. 2. What are the different types of Starters to control AC-Motor. Explain briefly. 3. Explain DOL starter of Single Phase Induction Motor briefly. 4. What is the purpose of the magnetic contactor? 5. What is the use of auxiliary contact in the magnetic controller? 6. What happens when the holding coil gets the supply in the magnetic controller? 7. Explain the working principle of a relay.arrow_forward
- 6- The injected e.m.f in the rotor of induction motor must have (a) The same frequency as the slip frequency. (c) A high value for satisfactory speed control. (d) The same phase as the rotor e.m.f and a high value for satisfactory speed control. (b) The same phase as the rotor e.m.f.arrow_forwardWhat are the advantages of a mechanically held relay?arrow_forwardWhat is the function of the field loss relay?arrow_forward
- Overhauling is a condition in which the motor’s armature rotates ( ] than the rotating stator field. A) more slowley B) more rapidlyarrow_forward14. Under line voltage control of induction motor the speed regulation occurs: a) by change of the slip of the motor. b) by change of the synchronous speed of the motor. c) by adding additional resistance in the rotor circuit. d) by changing the stator resistance of the motor.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_forward
- DEGREE: ELECTRICAL ENGINEERING SUBJECT/COURSE: AC MACHINES Answer the following questions (A, B and C) depending on the topic. 1. SYNCHRONOUS MOTORS A. What is necessary to start a synchronous motor to rotate from standstill? Describe the process. B. What is meant by synchronous condenser? C. Why is it possible for synchronous motors be used as a power factor correction device and what applications do synchronous motors commonly used? Describe the operation.arrow_forwardCompare the properties of induction motor and synchronous motor.arrow_forwardB)- Draw a neat diagram to show the armature diverter method for speed control DC series motorsarrow_forward
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