Understanding Motor Controls
4th Edition
ISBN: 9781337798686
Author: Stephen L. Herman
Publisher: Delmar Cengage Learning
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Question
Chapter 37, Problem 9RQ
To determine
The size of the conductor, overload size, circuit breaker size, NEMA and IEC starter sizes, the upper and lower range of the starting current for the motor.
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Students have asked these similar questions
The working current has a power of 100 kW and a power factor of 0.50. After a capacitor of 75 KVAR is installed, what does the
power factor become?
A 0.84
B 0.71
C 0.63
D 0.78
E 0.92
The following data were obtained on a 50 kVA 2400/120 V transformer:
Open circuit test, instruments on low voltage side:
Waltmeter reading = 396 Watts
Ammeter reading = 9.65 amperes
Voltmeter reading = 120 Volts
Short circuit test, instruments on high voltage side:
Waltmeter reading = 810 Watts
Ammeter reading = 20.8 amperes
Voltmeter reading = 92 Volts
Find the efficiency when rated kVA is delivered to a load having a power
factor of 0.8 lagging.The following data were obtained on a 50 kVA 2400/120 V transformer :
Open circuit test, instruments on low voltage side:
Waltmeter reading = 396 Watts
Ammeter reading = 9.65 amperes
Voltmeter reading = 120 Volts
Short circuit test, instruments on high voltage side:
Waltmeter reading = 810 Watts
Ammeter reading = 20.8 amperes
Voltmeter reading = 92 Volts
Find the efficiency when rated kVA is delivered to a load having a power
factor of 0.8 lagging.
In a given DC motor, the output power is 20 HP, and the copper losses are 1.1 KW. If the motor is operating at 87 % efficiency, find the converted power and the rotational losses. Select one:
a. Pconv = 16.05 KW and Prot = 1.13 KW
b. Pconv = 17.15 KW and Prot = 3.11 KW
c. Pconv = 14.92 KW and Prot = 1.35 KW
d. None
Chapter 37 Solutions
Understanding Motor Controls
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Similar questions
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- In the experiment No.4, the core loss component current is given by_ Ic Sinôo lo Sindo lc Cos&o lo Cosoarrow_forwardQuestion 4 A 228 V/ 111 V single-phase transformer has a core loss of 110 W and the no-load current is 0.7 A. The no load power factor is Not yet answered Marked out of O 0.99 1.00 O 1.42 P Flag question O 0.48 O 0.69 Question 5 A 2 kV / 229 V transformer has the secondary turns of 47. The number of Primary turns of a transformer is given by, Not yet answered 63.83 Marked out of 410.48 1.00 O 615.72 P Flag question O 5381.50 Question 6 For the given power transfer, a delta system is associated with larger line currents and a star system is associated with a larger line voltage. Not yet answered Select one: Marked out of O True 1.00 P Flag question O Falsearrow_forwardA balanced star-connected load of (8 + j6) Q per phase is connected to a Balanced 3- phase 400-V supply. Find the line current, power factor, powerarrow_forward
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