Electrical Transformers and Rotating Machines
4th Edition
ISBN: 9781305494817
Author: Stephen L. Herman
Publisher: Cengage Learning
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Chapter 8, Problem 2RQ
Two transformers rated at 100 kVA each are connected in an open-delta connection. What is the total output power that can be supplied by this bank?
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If the core loss of single phase transformer at full load is 134 W, then the core loss at 50% of load
is
8W
34W
134W
67W
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 the parallel connection below, what is the total power consumption?
R=30
R2= 60
V 9V
O 36.5 W
O 40.5 W
O 13.5 W
27 W
Chapter 8 Solutions
Electrical Transformers and Rotating Machines
Ch. 8 - How many transformers are needed to make an...Ch. 8 - Two transformers rated at 100 kVA each are...Ch. 8 - Prob. 3RQCh. 8 - Assume that a line voltage of 2400 volts is...Ch. 8 - Prob. 5RQCh. 8 - How much current is flowing through the secondary...Ch. 8 - How much current is flowing through the primary...Ch. 8 - Prob. 8RQCh. 8 - Prob. 9RQCh. 8 - How much current is flowing in the secondary...
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