Electric Motor Control
10th Edition
ISBN: 9781133702818
Author: Herman
Publisher: CENGAGE L
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Textbook Question
Chapter 12, Problem 7SQ
When the thermostat contacts close the blower motor starts but the heating elements never turn on. Which of the following could cause this problem?
- a. The flow switch is defective.
- b. The fan thermostat is defective.
- c. CR relay coil is open.
- d. Timed contact T2 is defective.
FIG. 12–10 Air flow must be present before heating elements can be energized.
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- Switching, Cords and Cables, Motors, and Related Systems
15.a. Information such as manufacturer's name or identification, rated voltage, rated current or HP, and shortcircuit current rating, along with any other information necessary to indicate their suitable application,should be found marked on what part of a motor circuit?A. The controllerB. The overload protectorC. The power source
15.b. What condition must be met to permit the attachment plug and receptacle or cord connector to act asthe disconnect for an A/C?A. The unit is 1 φ and not over 250 V.B. The unit is 5 φ and not over 300 V.C. The unit is 20 φ and not over 100 V.D. The unit is 10 φ and not over 200 V.
Chapter 12 Solutions
Electric Motor Control
Ch. 12 - Prob. 1SQCh. 12 - Draw a line diagram to show that a green light...Ch. 12 - Draw a one-line diagram showing a bell that will...Ch. 12 - To answer the following questions refer to Figure...Ch. 12 - When the thermostat contacts close, the blower...Ch. 12 - When the thermostat contacts close, the blower...Ch. 12 - When the thermostat contacts close the blower...
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