Electrical Machines In a synchronous motor when the rotor speed exceeds the synchronous speed during hunting the damper bars develop induction generator torque. negative sequence currents are generated. the damper bars develop synchronous motor torque. the damper bars develop induction motor torque. the damper bars develop induction generator torque. negative sequence currents are generated. the damper bars develop synchronous motor torque. the damper bars develop induction motor torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The polarity of a DC generator can be reversed by reversing the field current. reversing field electric current as well as direction of rotation. any of above. increasing field current. reversing the field current. reversing field electric current as well as direction of rotation. any of above. increasing field current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the mechanical power developed by a DC series motor is maximum? None of above. Back emf is equal to half the applied voltage. Back emf is equal to applied voltage. Back emf is equal to zero. None of above. Back emf is equal to half the applied voltage. Back emf is equal to applied voltage. Back emf is equal to zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following DC motors has almost constant speed over their full load range? none of these. Shunt. Compound (cummolative). Series. none of these. Shunt. Compound (cummolative). Series. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 250 volt dc series motor having an armature resistance of 0.2 Ω takes a load current of 60 A. What will be the torque produced at the shaft of the motor? Consider brush drop of 1V. 266.20 N-m. 234.76 N-m. can not be determined. 133.22 N-m 266.20 N-m. 234.76 N-m. can not be determined. 133.22 N-m 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. 0.5 at 90°C. 1 at 90°C. 3 at 90°C. 2 at 90°C. 0.5 at 90°C. 1 at 90°C. 3 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS