Electrical Machines If starter is not used with large DC motor for starting, it will provide execessive voltage drop in line. draw a starting current many times its rated full load current. damage the armature and commutator. all of above. provide execessive voltage drop in line. draw a starting current many times its rated full load current. damage the armature and commutator. all of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The sparking at the the brushes, in a DC machines is due to presence of commutator. armature reaction. high resistance of carbon brushes. reactance voltage. presence of commutator. armature reaction. high resistance of carbon brushes. reactance voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is not a necessary condition to be satisfied for synchronising an incoming alternator to an already operating alternator? same phase sequence same prime mover speed same voltage magnitude same frequency same phase sequence same prime mover speed same voltage magnitude same frequency ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Compensating winding is placed in the main field All of these armature core pole shoe main field All of these armature core pole shoe ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC motor under constant terminal voltage what is the relation between torque (Te) and power (P) T∝ P² T∝ P³ T∝ P T is independent of P T∝ P² T∝ P³ T∝ P T is independent of P ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of generated emf in the armature coil of a DC machine is 1. the same as that of the current in a generator 2. the same as that of the current in a motor 3. opposite to that of the current in a generator 4. opposite to that of the current in a motor From these, the correct answer is 2, 3 1, 3 1, 4 2, 4 2, 3 1, 3 1, 4 2, 4 ANSWER DOWNLOAD EXAMIANS APP