Electrical Transformers and Rotating Machines
4th Edition
ISBN: 9781305494817
Author: Stephen L. Herman
Publisher: Cengage Learning
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Question
Chapter 21, Problem 10RQ
To determine
The size of conductor for the branch circuit supply.
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Students have asked these similar questions
A 3 kVA motor operates from a 240 V
supply at 50 Hz and has a power
factor of 0.6. Determine the active
power
Select one:
1800 W
Non of the Answers
1900 W
2000 W
A 3-phase, 50 Hz, 3000 V motor develops 600 H.P. (447·6 kW), the power factor being 0·75 lagging andthe efficiency 0·93. A bank of capacitors is connected in delta across the supply terminals and powerfactor raised to 0·95 lagging. Each of the capacitance units is built of five similar 600-V capacitors.Determine the capacitance of each capacitor.
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.
Chapter 21 Solutions
Electrical Transformers and Rotating Machines
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Similar questions
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- Question 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_forwardTwo shunt generators 1 and 2 are operating in parallel. The voltage of generator 1 falls from 240 V at no-load to 220 V at 200 A, while that of generator 2 falls from 245 V at no-load to 220 at 150 A. Determine the current which each generator supplies to n common load of 300 A and the bus-bar voltage at this load. The load characteristics of the generators may be taken as straight lines.arrow_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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