Electrical Machines Maximum allowable tan - delta (tanδ) of dielectric dispassion factor of power transformer insulating oil is generally taken as 3 at 90°C. 0.5 at 90°C. 2 at 90°C. 1 at 90°C. 3 at 90°C. 0.5 at 90°C. 2 at 90°C. 1 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the rotor speed, in a synchronous machine, becomes more than the synchronous speed during hunting, the damper bars develop synchronous motor torque. induction generator torque. DC motor torque. induction motor torque. synchronous motor torque. induction generator torque. DC motor torque. induction motor torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the handle of a three point starter goes to back to OFF position, it may be due to zero or very low voltage supply. high filed circuit resistance. all of these. over load. zero or very low voltage supply. high filed circuit resistance. all of these. over load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cogging and crawling are phenomena associated with the former at a fraction of its rate speed and the latter during starting. any of the above. the former during starting and the latter at a fraction of its rated speed. cage induction machines and they are essentially the same. the former at a fraction of its rate speed and the latter during starting. any of the above. the former during starting and the latter at a fraction of its rated speed. cage induction machines and they are essentially the same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In speed control of DC shunt motor by varying field flux, what may be the value of field regulator? 100 ohm 0.2 ohm 2 ohm. 10 ohm 100 ohm 0.2 ohm 2 ohm. 10 ohm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If field current is decreased in shunt dc motor, the speed of the motor remains same. increases. decreases. None of these remains same. increases. decreases. None of these ANSWER DOWNLOAD EXAMIANS APP