Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.443. 0.512. 0.573. 0.649. 0.443. 0.512. 0.573. 0.649. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Crawling in an induction motor is due to slip ring rotor. time harmonics in supply. space harmonics produced by winding currents. insufficient starting torque. slip ring rotor. time harmonics in supply. space harmonics produced by winding currents. insufficient starting torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When a synchronous motor is running at synchronous speed, the damper winding produces no torque. damping torqe. both 1 and 2. eddy current torque. no torque. damping torqe. both 1 and 2. eddy current torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A large series motor is never started without some mechanical on it because otherwise it will Open fuse or circuit breaker. Develop excessive speed and damage itself. Draw too much current. Produce sparking at brushes. Open fuse or circuit breaker. Develop excessive speed and damage itself. Draw too much current. Produce sparking at brushes. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The DC generator runs at a speed of 1000 rpm and flux per pole is 0.2 Wb, number of poles are 2 the winding is wave wound and having 480 conductors. The critical speed is 1200 rpm. Then the generated emf ( Eg ) 0 Volt. 2000 Volt. 1500 Volt. 1600 Volt. 0 Volt. 2000 Volt. 1500 Volt. 1600 Volt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are the methods to reduce the armature reaction and its effects? pole chamfering pole stacking compensating winding All of these pole chamfering pole stacking compensating winding All of these ANSWER DOWNLOAD EXAMIANS APP