20. A single-phase, 120 V, 60 Hz, four-pole, split-phase induction motor has the following equivalent circuit parameters: R1m=1.52, R1a=2.52, R'2=12, X 1m=2.52, X1a =2.52, X2=1.52, Xmag =402 a) Determine the standstill impedances (Zm, Za) of the windings. b) Determine the starting torque and the starting current of the motor if it is started from rated voltage mains as a resistor split-phase motor. c) Determine the value of the capacitor to be connected in series with the auxiliary winding to produce maximum starting torque per ampere of starting current. Determine the value of the starting torque and starting current. d) Compare the starting torque per ampere of starting current for cases (b) and (c).

20. A single-phase, 120 V, 60 Hz, four-pole, split-phase induction motor has the following equivalent circuit parameters: R1m=1.52, R1a=2.52, R'2=12, X 1m=2.52, X1a =2.52, X2=1.52, Xmag =402 a) Determine the standstill impedances (Zm, Za) of the windings. b) Determine the starting torque and the starting current of the motor if it is started from rated voltage mains as a resistor split-phase motor. c) Determine the value of the capacitor to be connected in series with the auxiliary winding to produce maximum starting torque per ampere of starting current. Determine the value of the starting torque and starting current. d) Compare the starting torque per ampere of starting current for cases (b) and (c).

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter8: Basic Electric Motors

Section: Chapter Questions

Problem 28RQ: What are the advantages and disadvantages of using the following types of motors? shaded-pole...

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