Q5) A 10 kW, 400 V, 3 phase, 4pole, 50 Hz, slip ring induction motordevelops its rated output at rated voltage and frequency and with its slipample 7:rings short circuited. The maximum torque equal to twice the full loadhe test datrtorque, occurs at a slip of 0.1. Stator impedance and rotational losses1710 rpmare neglected (use approximate equivalent circuit). Determine:The staa- The slip and rotor speed at full load torque. (Ans: Sn= 0.026, Nr=1459.8 r.p.m)b- The starting current in terms of full load current. (Ans: Is=0.103 In)c- The rotor copper losses at full load torque. (Ans: 275.38 watt)d- The starting torque at rated voltage and frequency. (Ans:25.9N.m)The rotor resistance is now trebled by inserting external resistance inthe rotor circuit. Find3;e- The slip at maximum torque. (Ans: S^= 0.3)

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Q5) A 10 kW, 400 V, 3 phase, 4pole, 50 Hz, slip ring induction motor develops its rated output at rated voltage and frequency and with its slip rings short circuited. The maximum torque equal to twice the full load torque, occurs at a slip of 0.1. Stator impedance and rotational losses are neglected (use approximate equivalent circuit). Determine: a- The slip and rotor speed at full load torque. (Ans: Sn= 0.026, Nr= 1459.8 r.p.m) b- The starting current in terms of full load current. (Ans: Is=0.103 In C- The rotor copper losses at full load torque. (Ans: 275.38 watt) d- The starting torque at rated voltage and frequency. (Ans:25.9 N.m) The rotor resistance is now trebled by inserting external resistance in the rotor circuit. Find3; e- The slip at maximum torque. (Ans: SA= 0.3)

Q5) A 10 kW, 400 V, 3 phase, 4pole, 50 Hz, slip ring induction motor develops its rated output at rated voltage and frequency and with its slip rings short circuited. The maximum torque equal to twice the full load torque, occurs at a slip of 0.1. Stator impedance and rotational losses are neglected (use approximate equivalent circuit). Determine: a- The slip and rotor speed at full load torque. (Ans: Sn= 0.026, Nr= 1459.8 r.p.m) b- The starting current in terms of full load current. (Ans: Is=0.103 In C- The rotor copper losses at full load torque. (Ans: 275.38 watt) d- The starting torque at rated voltage and frequency. (Ans:25.9 N.m) The rotor resistance is now trebled by inserting external resistance in the rotor circuit. Find3; e- The slip at maximum torque. (Ans: SA= 0.3)

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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