Electrical Machines Resistance commutation is used generally in case of DC machines bellow 5 kW. None of these fractional kW DC machines. DC machines above 10 kW. DC machines bellow 5 kW. None of these fractional kW DC machines. DC machines above 10 kW. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To eliminate 5th harmonic in the induced voltage phase breadth should be 18° 36° 72° 30° 18° 36° 72° 30° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A large series motor is never started without some mechanical load on it because otherwise it will produce sparking at brushes. draw too much current. open fuse or circuit breaker. develop excessive speed and damage itself. produce sparking at brushes. draw too much current. open fuse or circuit breaker. develop excessive speed and damage itself. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motors has negative speed regulation? Differential compound motors. Series motors. Shunt motors. Both B and C. Differential compound motors. Series motors. Shunt motors. Both B and C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the no-voltage release in a DC motor starter fails to operate on failure of supply, on resumption of supply the motor will start automatically without trouble. not start automatically. develop very low starting torque. get damaged. start automatically without trouble. not start automatically. develop very low starting torque. get damaged. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a induction motor helps to increase the starting torque. reduce the magnetizing current. reduce the chance of cogging. reduce the chance of crawling. increase the starting torque. reduce the magnetizing current. reduce the chance of cogging. reduce the chance of crawling. ANSWER DOWNLOAD EXAMIANS APP