Electrical Machines Induction motors have the advantage of simple in construction. all of below. less cost. less maintenance. simple in construction. all of below. less cost. less maintenance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a star - delta starting of an IM resistance is inserted in the rotor. reduced voltage is applied to the stator. line voltage is 57.7 % of stator voltage. applied voltage per stator phase is 57.7 % of a line volt resistance is inserted in the rotor. reduced voltage is applied to the stator. line voltage is 57.7 % of stator voltage. applied voltage per stator phase is 57.7 % of a line volt ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 4 pole IM is supplied from a 50 Hz source. Calculate rotor frequency when rotor runs 600 rpm? Can be determined. 35 Hz. 20 Hz. 30 Hz. Can be determined. 35 Hz. 20 Hz. 30 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In star-delta starting of squirrel cage induction motor compared to DOL starting the starting current and torque are 1/√3, 1/√3 1/3, 1/3 1/√3, 1/3 1/3, 1/√3 1/√3, 1/√3 1/3, 1/3 1/√3, 1/3 1/3, 1/√3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the efficiency when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 82.5% 72.5% 78.5% 67.5% 82.5% 72.5% 78.5% 67.5% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3- phase synchronous motor can operate over a wide range of power factors i.e. from lagging to leading power factor. This is achieved by changing the load. varying the speed. varying the applied voltage. changing the field excitation. changing the load. varying the speed. varying the applied voltage. changing the field excitation. ANSWER DOWNLOAD EXAMIANS APP
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