Industrial Motor Control
7th Edition
ISBN: 9781133691808
Author: Stephen Herman
Publisher: Cengage Learning
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Chapter 49, Problem 8RQ
Refer to the circuit shown in Figure 49–20. Assume that the THIRD SPEED push button is pressed. The motor starts in it second speed, skipping first speed. After 5 seconds the motor accelerates to third speed. Which of the following could cause this problem?
- a. S1 contactor coil is open.
- b. CR1 contactor coil is open.
- c. TR1 timer coil is open.
- d. S1 load contacts are shorted.
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A piston–cylinder device contains 3 kg of nitrogen initially at 100 kPa and 25°C. Nitrogen is now compressed slowly in a polytropic process during which PV1.3 = constant until the volume is reduced by one-half. Determine the work done and the heat transfer for this process. The gas constant of N2 is R = 0.2968 kPa·m3/kg·K. The cv value of N2 at the anticipated average temperature of 350 K is 0.744 kJ/kg·K (Table A-2b).
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Chapter 49 Solutions
Industrial Motor Control
Ch. 49 - Prob. 1RQCh. 49 - What is the advantage of a plunger-type voltage...Ch. 49 - A motor is tripping out on overload. The motor...Ch. 49 - A motor is tripping out on overload. The motor...Ch. 49 - Prob. 5RQCh. 49 - Refer to the circuit shown in Figure 4916. Assume...Ch. 49 - Prob. 7RQCh. 49 - Refer to the circuit shown in Figure 49–20. Assume...Ch. 49 - Prob. 9RQCh. 49 - Refer to the circuit shown in Figure 4920. Assume...
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