Electric Motor Control
10th Edition
ISBN: 9781133702818
Author: Herman
Publisher: CENGAGE L
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Textbook Question
Chapter 36, Problem 6SQ
Referring to Figure 36–4, why is it not possible to remove all of the resistance from the secondary circuit?
Fig. 36–4 Automatic acceleration of wound rotor motor using a simplified frequency relay system.
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Chapter 36 Solutions
Electric Motor Control
Ch. 36 - Are the secondary resistors connected in three...Ch. 36 - Do secondary resistors on starters with three or...Ch. 36 - Does reversing the secondary rotor leads mean that...Ch. 36 - If one of the secondary resistor contacts (S2)...Ch. 36 - In Figure 362, how many different interlocking...Ch. 36 - Referring to Figure 364, why is it not possible to...Ch. 36 - Prob. 7SQCh. 36 - If there is a locked rotor in the secondary...Ch. 36 - Why is it necessary to remove the jumpers in...Ch. 36 - Prob. 10SQ
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- 4.a. The device which responds to the heat developed within the motor is theA. shading coil.B. short-circuiter.C. bimetallic protector.D. current-operated relay.4.b. How is a rotating magnetic field produced during starting in a split-phase motor?A. A capacitor is inserted in the auxiliary-winding circuit.B. A low resistance coil is placed around a portion of each pole.C. Brushes are shifted off the hard-neutral position.D. An auxiliary winding is made with a high ratio of resistance to reactance.arrow_forwardA three-phase, six-pole, 60 Hz, 230-volt wound rotor motor has its stator connected in delta and its rotor in star. There are 70 percent as many rotor conductors as stator conductors as stator conductors. Calculate the voltage and frequency between slip rings if normal voltage is applied to the stator when, a, the rotor is at rest, b. the rotor slip is 0.04arrow_forward__________induction motor is an AC motor that provides variable speed control by varying the resistance of its rotor. a. Synchronous b. Squirrel-cage c. Wound-rotor d. Split-phasearrow_forward
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- A 460 V, 60 Hz, Star connected, 870 r.p.m., Eight poles, Three-Phase Induction Motor has the following per phase parameters: R1 = 0.07, R2 = 0.05, X1 = X2 = 0.2, Xm = 6.5, Draw the exact equivalent circuit and determine the following: VII. Rotor Current VIII. Magnetizing Currentarrow_forwardQuestion is from book electric machine 1 topic induction motor We need to derive an oil burner with single phase induction motor. Suggestthe best type of single phase induction motor that can be suited for this purpose.1) Explain why you suggest this type of motor and also explain its working principlein detail with the help of cross field theory. Diagrams are necessary. Please give me the answere or as short as you arearrow_forward(a) Draw and explain slip-torque characteristics of 3-phase induction motor. (b) No load and blocked rotor test of a 440 V, three phase 55 HP, star connected induction motor gave the following results No-load (line values) : 440 V, 5 A , 230 W Blocked rotor test (Line values) : 130 V, 15 A , 1800 W Stator resistance per phase is 1.2 Q. Calculate the parameters of exact equivalent circuit and draw the exact equivalent circuit referred to stator side.arrow_forward
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