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 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 varying the speed. changing the field excitation. changing the load. varying the applied voltage. varying the speed. changing the field excitation. changing the load. varying the applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A single phase transformer has specifications as 250 KVA, 11000 V/415 V, 50 Hz. What are the values of primary and secondary currents? primary = 11.4 A, secondary = 301 A primary = 301 A, secondary = 22.7 A primary = 22.7 A, secondary = 602.4 A primary = 602 A, secondary = 22.7 A primary = 11.4 A, secondary = 301 A primary = 301 A, secondary = 22.7 A primary = 22.7 A, secondary = 602.4 A primary = 602 A, secondary = 22.7 A ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 5 KVA transformer has a turns ratio of N1/N2 = 10. The impedance of primary winding is 3+j5 ohms while that of secondary winding is 0.5+j0.8 ohms. The impedance of transformer when referred to primary will be 3.05+j5.08 ohms 3.5+j5.8 ohms 53+j85 ohms 8+j13 ohms 3.05+j5.08 ohms 3.5+j5.8 ohms 53+j85 ohms 8+j13 ohms ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generators brushes are used for collecting of current without any sparkings convert ac armature current in to dc reduce eddy current loss collecting of voltage collecting of current without any sparkings convert ac armature current in to dc reduce eddy current loss collecting of voltage ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor the 7th harmonic torque may make the motor rotate at (1 / 7)th synchronous speed. This is called cogging. harmonics. resonance. crawling. cogging. harmonics. resonance. crawling. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS