A 3-phase, 2200-V, delta-connected, 12-pole 60-Hz induction motor runs at no load with rated voltage and frequency impressed and draws a line current of 20 Amp. and an input power of 14 Kw. The stator is Y-connected, and its resistance per phase is 0.4 Ohm. The rotor resistance r2 ’ is 0.2 Ohm per phase. Also, x1+x2'=2.0 Ω per phase. The motor runs at a slip of 2% when it is delivering power to a load. For this condition, determine a) The developed torque. b) The input line current and power factor.

A 3-phase, 2200-V, delta-connected, 12-pole 60-Hz induction motor runs at no load with rated voltage and frequency impressed and draws a line current of 20 Amp. and an input power of 14 Kw. The stator is Y-connected, and its resistance per phase is 0.4 Ohm. The rotor resistance r2 ’ is 0.2 Ohm per phase. Also, x1+x2'=2.0 Ω per phase. The motor runs at a slip of 2% when it is delivering power to a load. For this condition, determine a) The developed torque. b) The input line current and power factor.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 13RQ: A squirrel-cage induction motor is operating at 1175 RPM and producing a torque of 22 Ib-ft. What is...

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