Electrical Machines Field weakening control method is used for the _________ ? below rated speed above rated speed None of these both A and B below rated speed above rated speed None of these both A and B ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For the speed control of polyphase squirrel cage induction motor, if frequency of operation is decreased with either of these None of these constant supply voltage V, starting torque Tst decreases constant V, Tst increases either of these None of these constant supply voltage V, starting torque Tst decreases constant V, Tst increases ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Damper winding is used to decrease the load current. suppress the hunting. both 1 and 2. increase the load current. decrease the load current. suppress the hunting. both 1 and 2. increase the load current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For 250 volt DC Shunt Motor the armature and field resistance are 0.5 ohm and 250 ohm respectively. What will be the back e.m.f. produced when it takes a load current of 21A. 240 V. 280 V. 220 V. 150 V. 240 V. 280 V. 220 V. 150 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increases in field excitation of a DC generator, its generated emf remains constant. increases. increases upto a limit and then remains almost constant. decreases. remains constant. increases. increases upto a limit and then remains almost constant. decreases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the necessity of copper brushes in a dc motors? To convert alternating supply current to direct current. To increase the flux cutting by the rotor. None of these. To absorb the mechanical shocks produced during running condition. To convert alternating supply current to direct current. To increase the flux cutting by the rotor. None of these. To absorb the mechanical shocks produced during running condition. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS