Electrical Machines A 4 pole 50 Hz induction motor is running at 1470 rpm. Find the speed of stator magnetic field with respect to rotor? 1470 rpm 1500 rpm zero 30 rpm 1470 rpm 1500 rpm zero 30 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In field flux method speed control of DC Motor is constant hp drive below the base speed. constant power drive above base speed. constant torque drive above the base speed. constant torque drive below the base speed. constant hp drive below the base speed. constant power drive above base speed. constant torque drive above the base speed. constant torque drive below the base speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Thin laminations are used in a machine in order to reduce Copper losses Both 1 and 2 Hysteresis losses Eddy current losses Copper losses Both 1 and 2 Hysteresis losses Eddy current losses ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum allowable tan - delta (tanδ) of dielectric dispassion factor of power transformer insulating oil is generally taken as 2 at 90°C. 3 at 90°C. 0.5 at 90°C. 1 at 90°C. 2 at 90°C. 3 at 90°C. 0.5 at 90°C. 1 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Compensating windings are used in DC generators to neutralize the cross magnetizing effect of the armature reaction. mainly to reduce the eddy currents by providing local short circuit. None of these to provide path for the circulation of cooling air. to neutralize the cross magnetizing effect of the armature reaction. mainly to reduce the eddy currents by providing local short circuit. None of these to provide path for the circulation of cooling air. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a induction motor helps to reduce the magnetizing current. reduce the chance of cogging. reduce the chance of crawling. increase the starting torque. reduce the magnetizing current. reduce the chance of cogging. reduce the chance of crawling. increase the starting torque. ANSWER DOWNLOAD EXAMIANS APP