Electrical Machines What is/are the necessary conditions for voltage build up in self excited generator? Poles should contain residual flux. Field winding resistance should be less than critical resistance. All of these Field winding should be properly connected to armature winding. Poles should contain residual flux. Field winding resistance should be less than critical resistance. All of these Field winding should be properly connected to armature winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines At the instant of starting, the per unit slip of 3 - Φ induction motor is 0.1. 0.5. 0.05. 1.0. 0.1. 0.5. 0.05. 1.0. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines As compared to an induction motor, the air gap in a DC motor is same. less than 50%. between 50% and 90%. more. same. less than 50%. between 50% and 90%. more. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cogging and crawling are phenomena associated with cage induction machines and they are essentially the same. any of the above. the former during starting and the latter at a fraction of its rated speed. the former at a fraction of its rate speed and the latter during starting. cage induction machines and they are essentially the same. any of the above. the former during starting and the latter at a fraction of its rated speed. the former at a fraction of its rate speed and the latter during starting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC shunt generator builds up to a voltage of 220 V at no load while running at its rated speed. If the speed of the generator is raised by 25% kepping the circuit conditions unaltered, then the Voltage to which the machine would build up will increase to 1.25 times 220 V increase to a value greater than 1.25 times 220 V increase to value lying between 220 V and 1.25 times 220 V not change and remain at 220 V increase to 1.25 times 220 V increase to a value greater than 1.25 times 220 V increase to value lying between 220 V and 1.25 times 220 V not change and remain at 220 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To control the speed of an induction motor, the supply frequency is reduced by 10%. For the same magnetizing current to remain constant, the supply voltage must be reduced by 20% increased by 10% increased by 20% reduced by 10% reduced by 20% increased by 10% increased by 20% reduced by 10% ANSWER DOWNLOAD EXAMIANS APP