Understanding Motor Controls
4th Edition
ISBN: 9781337798686
Author: Stephen L. Herman
Publisher: Delmar Cengage Learning
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Chapter 42, Problem 3RQ
A motor is tripping out on overload. The motor nameplate reveals a full load current of 68 amperes. When the motor is operating under load, an ammeter indicates the following: Phase #1 = 106 amperes, Phase #2 = 104 amperes, and Phase #3 = 105 amperes. What is the most likely problem with this motor?
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Chapter 42 Solutions
Understanding Motor Controls
Ch. 42 - What are the three main electrical test...Ch. 42 - What is the advantage of a plunger type voltage...Ch. 42 - A motor is tripping out on overload. The motor...Ch. 42 - A motor is tripping out on overload. The motor...Ch. 42 - Prob. 5RQCh. 42 - Refer to the circuit shown in Figure 42–17. Assume...Ch. 42 - Prob. 7RQCh. 42 - Refer to the circuit shown in Figure 4221. Assume...Ch. 42 - Prob. 9RQCh. 42 - Refer to the circuit shown in Figure 42–21. Assume...
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- A motor develops 225 ft-lb of torque at 860 RPM. What is the horsepower output of the motor?arrow_forward1. What will be the output voltage during the positive half cycle of the input voltage? 2. What will be the output voltage during the negative half cycle of the input voltage?arrow_forwardA wye-connected load has a voltage of 480 V applied to it. What is the voltage dropped across each phase?arrow_forward
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