Electrical Machines For satisfactory parallel operation of two transformers which of the following conditions is most essential, percentage impedance of all transformers must be same. polarities of all transformers must be same. voltage ratio of all transformers must be same. MVA rating of all transformer inversely proportional to impedance. percentage impedance of all transformers must be same. polarities of all transformers must be same. voltage ratio of all transformers must be same. MVA rating of all transformer inversely proportional to impedance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Wave winding is prefered for which of the following rating? high current and low voltage low current and high voltage high current and high voltage low current and low voltage high current and low voltage low current and high voltage high current and high voltage low current and low voltage ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the frequency of a alternator, if P = number of poles and N = revolution made per second? 120P / N Hz. 120N / P Hz. 120 / PN Hz. PN / 2 Hz. 120P / N Hz. 120N / P Hz. 120 / PN Hz. PN / 2 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Transformer cooling and insulating oil must be of low resistivity. high viscosity. low BDV. low viscosity. low resistivity. high viscosity. low BDV. low viscosity. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc generator operating on load with its brushes on the geometrical neutral axis (GNA), the magnetic neutral axis (MNA) is shifted in the direction of rotation. Now, if the brushes are given a lead of 90° (electrical), then the MNA will coincide with the GNA shift forward by 90° shift forward by more than 90° shift forward by less than 90° coincide with the GNA shift forward by 90° shift forward by more than 90° shift forward by less than 90° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In synchronous motor, the damper winding is generally used to reduce the eddy currents. provide starting torque only. prevent hunting and provide the starting torque. reduce noise level only. reduce the eddy currents. provide starting torque only. prevent hunting and provide the starting torque. reduce noise level only. ANSWER DOWNLOAD EXAMIANS APP