Electrical Machines What is the frequency of a alternator, if P = number of poles and N = revolution made per second? 120N / P Hz. 120 / PN Hz. 120P / N Hz. PN / 2 Hz. 120N / P Hz. 120 / PN Hz. 120P / N Hz. PN / 2 Hz. 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 What is/are the necessary conditions for voltage build up in self excited generator? Poles should contain residual flux. Field winding resistance should be less than critical resistance. All of these Field winding should be properly connected to armature winding. Poles should contain residual flux. Field winding resistance should be less than critical resistance. All of these Field winding should be properly connected to armature winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor is, in general analogous to two winding transformer with secondary open circuited. two winding transformer with secondary short circuited. auto transformer. None of these two winding transformer with secondary open circuited. two winding transformer with secondary short circuited. auto transformer. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous motor is supplying a load at unity power factor. If the load on the motor is increased keeping its excitation and terminal voltage constant, the power factor will remain the same None of these will become lagging will become leading will remain the same None of these will become lagging will become leading ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Centrifugal switch is absent in which of the single phase induction motor? PSC (permanent split capacitor) motor. None of these Split phase motor. Shaded pole motor. PSC (permanent split capacitor) motor. None of these Split phase motor. Shaded pole motor. ANSWER DOWNLOAD EXAMIANS APP