Electric Motor Control
10th Edition
ISBN: 9781133702818
Author: Herman
Publisher: CENGAGE L
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Chapter 52, Problem 8SQ
To determine
Explain the process of how a belt slack can be maintained on the top as shown in Figure 52-6.
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A 10-HP, 110-V, 3-phase, Y-connected, 60 Hz, 4 pole inductionmotor has the following test data: No load: 110 V, 21 A, 650 WBlocked-rotor: 24 V, 51 A, 1040 WStator resistance between terminals: 0.08 ohmThe motor has wound rotor. Assume that both stator and rotor windings arewye-connected.
a) If full voltage were applied to the stator with therotor terminals short-circuited, how much starting current would themotor draw?
b) If the ratio of transformation per phase of the motor is2, with the rotor having the greater turns, how much resistance should beadded to each phase of the rotor to limit the starting current of themotor to 75 A, when the voltage is applied to the stator?
A 13 kW, 198 V DC short-shunt motor, being fed through a feeder with total resistance of 0.04 ohms, has an armature, series field and shunt field resistances of 0.01 ohm, 0.02 ohm and 44 ohms, respectively. Find the armature voltage. 2 decimal places only
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Three phase, star connected, 480 V (line), 22 Kw, 60 Hz, 4 pole asynchronous motor has the following parameters.
Rs=0.24 Ohm
R’r=0.20 Ohm
Xs=1.3 Ohm
X’r=1.2 Ohm
Xm=37 Ohm
Total wind, friction and core losses are fixed and are 1300 W. Find the output power, generated power, efficiency and input power factor if the slip is 1% and 2% when the motor is directly connected to a 480 V source?
Chapter 52 Solutions
Electric Motor Control
Ch. 52 - What are the disadvantages of low-speed, directly...Ch. 52 - What type of AC motor can be directly coupled at...Ch. 52 - What three alignment checks should be made to...Ch. 52 - What special tools, not ordinarily carried by an...Ch. 52 - Prob. 5SQCh. 52 - Prob. 6SQCh. 52 - How tightly should V-belts be adjusted?Ch. 52 - Prob. 8SQCh. 52 - A machine delivered for installation has a 2-inch...
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