EBK ELECTRIC MOTOR CONTROL
10th Edition
ISBN: 9780100784598
Author: Herman
Publisher: YUZU
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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
(b) A de source is connected to stator
(e) One phase is open circaited
(d) Power is ied back to mains
10- Direct online (D.O.L.) starter is used for induction motors
(a)Less than 5 h.p. (b) Less than 10 h.p. (c) Greater than 10 h.p. (d) For any capacity
(b) Very low emf induced in the rotor
(d) Constant magnitude of flux linking the rotor core
of its full load rated current
Q
23. When the circuit breaker is always tripping, most likely
There is an overloading
c. The supply line are open
a.
b.
There is an over current
d. The load is removed
24. The synchronous motor is not inherently self- starting because
the rotating magnetic field does not have enough poles
b. the rotating magnetic field is produced by only 50 HZ frequency currents
the force required to accelerate the rotor is to the synchronous speed in an instant is
d. the starting devices to accelerate the rotor to near synchronous speed is absent
25. Synchronous motor has speed
a. slight drop in speed on full load
b.high speed at low torque
а.
с.
c. constant speed
d. low speed at high -
Chapter 29 Solutions
EBK ELECTRIC MOTOR CONTROL
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, electrical-engineering and related others by exploring similar questions and additional content below.Similar questions
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