Assume that a three-phase 700KW, 50 Hz, 4200V (Line to Line) Wye-connected induction motor has a full-load efficiency (n) of 100% and a lagging power factor of 0.75 and is connected to a feeder. If it is desired to correct the power factor of the load to a lagging power factor of 0.9 by connecting three capacitors (capacitor bank) at the load as shown in the figure a VLL b VLL IL Motor PF Lagging KW CAPACITOR BANK If QC is rating of the capacitor bank in KVAR that should be connected in parallel with motor and if C is the capacitance of each unit if the capacitors are connected in delta, in microfarads Taking two digits after comma, then QC and C will be Select one: O a. QC = 475.12 KVAR &C = 12.63 Microfarad Ob. QC = 675.12 KVAR &C = 42.63 Microfarad O. QC = 775.12 KVAR & C = 42.63 Microfarad Od. QC = 575.12 KVAR &C = 32.63 Microfarad O e. QC = 375.12 KVAR & C = 22.63 Microfarad Of. None of these

Assume that a three-phase 700KW, 50 Hz, 4200V (Line to Line) Wye-connected induction motor has a full-load efficiency (n) of 100% and a lagging power factor of 0.75 and is connected to a feeder. If it is desired to correct the power factor of the load to a lagging power factor of 0.9 by connecting three capacitors (capacitor bank) at the load as shown in the figure a VLL b VLL IL Motor PF Lagging KW CAPACITOR BANK If QC is rating of the capacitor bank in KVAR that should be connected in parallel with motor and if C is the capacitance of each unit if the capacitors are connected in delta, in microfarads Taking two digits after comma, then QC and C will be Select one: O a. QC = 475.12 KVAR &C = 12.63 Microfarad Ob. QC = 675.12 KVAR &C = 42.63 Microfarad O. QC = 775.12 KVAR & C = 42.63 Microfarad Od. QC = 575.12 KVAR &C = 32.63 Microfarad O e. QC = 375.12 KVAR & C = 22.63 Microfarad Of. None of these

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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4) A 40-kW induction motor, with a lagging power factor of 0.76 is supplied by a 120-Vrms, 60-Hz sinusoidal voltage source. Find the capacitance needed in parallel with the motor to raise the power factor to 0.9 lagging
Q3 A three-phase induction motor has the following data: 50 hp and V440 and 50HZ operating at full load with an efficiency of 89% and a power factor of0.85 lagging. Calculate the total apparent power of the capacitors to raise the power factor at full load to 0.95 lagging. What is the value of the capacitors' capacitance for each phase if we connect the capacitors (a) in the form of delta (b) in the form of a star.
H. W.: A 35 kW induction motor has power factor 0.9 and effliciency 0.9 at full-load, power factor 0.6 and efficiency 0.7 at half full-load. At no load the current is 25% of full-load current and power factor is 0.I. Capacitors are supplied to make the line power factor 0.8 at half full- load. With these capacitors in circuit, find the line power factor at: (i) full load, and (ii) no load.
A 40 kW induction motor, with a lagging power factor of 0.76, is supplied by a 120 V rms 60 Hz sinusoidal voltage source. Find the capacitance needed in parallel with the motor to raise the power factor to: (a) 0.9 lagging, and (b) 1.0.
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