Electrical Machines Which of the following is/are the advantages of carbon brush over the copper brush? They are self lubricating in nature They are not hard as copper brush In case of any sparking they will be less damaged than copper brushes All of these They are self lubricating in nature They are not hard as copper brush In case of any sparking they will be less damaged than copper brushes All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the excitation is reduced, the power factor is leading power factor lagging power factor None of these unity power factor leading power factor lagging power factor None of these unity power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Fufuraldehyde analysis is done to determine the condition of paper insulation in transformer. condition of cork gaskets used in transformer. condition of oil in transformer. condition of lamination on CRGO steel sheet. condition of paper insulation in transformer. condition of cork gaskets used in transformer. condition of oil in transformer. condition of lamination on CRGO steel sheet. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Under which of the following conditions hunting of synchronous motor is likely to occur ? Periodic variation of load. Over-loading for long period. Over-excitation. Small and constant load. Periodic variation of load. Over-loading for long period. Over-excitation. Small and constant load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a induction motor helps to increase the starting torque. reduce the chance of cogging. reduce the magnetizing current. reduce the chance of crawling. increase the starting torque. reduce the chance of cogging. reduce the magnetizing current. reduce the chance of crawling. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The squirrel cage induction motors are provided with blades in order to facilitate cooling of rotor. none of these. balance the rotor dynamically. eliminate noise. facilitate cooling of rotor. none of these. balance the rotor dynamically. eliminate noise. ANSWER DOWNLOAD EXAMIANS APP