Electric Motor Control
10th Edition
ISBN: 9781133702818
Author: Herman
Publisher: CENGAGE L
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Textbook Question
Chapter 29, Problem 1SQ
Indicate the correct terminal markings for a star-delta motor on Figure 29–9.
FIG. 29–9
Expert Solution & Answer
To determine
Specify the correct terminal markings of the star-delta motor in Figure 29-9.
Explanation of Solution
Star-delta motors:
The construction of star-delta motor is similar like standard type of squirrel cage motors. In star-delta motor, two ends of each of the three windings are brought out to terminals.
Refer Figure 29-9 in the textbook for the star-delta motor circuit. Modify the figure by mentioning the all-terminal markings and the modified circuit diagram as shown in Figure 1.
In Figure 1, T1, T2, T3, T4, T5, and T6 are the six leads of motor.
Conclusion:
Thus, the correct terminal markings are mentioned in the star-delta motor.
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Students have asked these similar questions
7- Iron loss in the rotor of a 3-phase induction motor is negligible due to
(a) Very low frequency of emf induced in the rotor
(c) Very low flux density in rotor parts
8- The starting current of a 3-phase induction motor is about
(a) Half
(c) 5 to 7 times
(b) Twice
(d) 8 to 10 times
9- During plugging of an induction motor
(a) Phase sequence is reversed
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of its full load rated current
23. When the circuit breaker is always tripping, most likely
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а.
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Calculate
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