Electrical Machines To achieve spark less commutation brushes of DC generator are rocked ahead so as to bring them None of these just ahead of magnetic neutral axis. in magnetic neutral axis. just behind the magnetic neutral axis. None of these just ahead of magnetic neutral axis. in magnetic neutral axis. just behind the magnetic neutral axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Slot wedges in a dc machine is made up of silicon steel. mild steel. fibre. cast iron. silicon steel. mild steel. fibre. cast iron. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf of a DC machine has trapezoidal space distribution and is stationary in space. triangular space distribution and is stationary in space. triangular space distribution and rotates at the speed of armature. stepped distribution and rotates at the speed of armature. trapezoidal space distribution and is stationary in space. triangular space distribution and is stationary in space. triangular space distribution and rotates at the speed of armature. stepped distribution and rotates at the speed of armature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following statements are correct ? Both 1 and 2. A small value of leakage reactance will increase the maximum power output of motor. None of these The leakage reactance of the induction motor should be small. Both 1 and 2. A small value of leakage reactance will increase the maximum power output of motor. None of these The leakage reactance of the induction motor should be small. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the highest possible speed of turbo alternators? 1500 rpm 3000 rpm 4000 rpm 1000 rpm 1500 rpm 3000 rpm 4000 rpm 1000 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The following statements relate to compensating winding (CW) and interpole winding (IW) of a dc machine : 1. CW neutralizes the armature reaction under a pole pitch 2. IW is connected in series with armature circuit 3. IW produces mmf in the commutating zone only 4. CWmmf is directed along the brush axis 5. Mmf produced by IW is equal to armature mmf From these, the correct statements are 1, 3, 4, 5 2, 3, 4, 5 1, 2, 3, 4 and 5 2, 3, 4 1, 3, 4, 5 2, 3, 4, 5 1, 2, 3, 4 and 5 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP