Electrical Machines In case the conditions for maximum power for DC motor are established, the efficiency of the motor will be Around 90 % Less than 50 % Any where between 75 % and 90 %. Around 100 %. Around 90 % Less than 50 % Any where between 75 % and 90 %. Around 100 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 ,V 15 , kW 100 rpm shunt motor with armature resistance of 0.25 , W has a rated line current of 68 A and a rated field current of 2.2 A. The change in field flux required to obtain a speed of 1600 rpm while drawing a line current of 52.8 A and a field current of 1.8 A is 36.36% increase 36.36% decrease 36.36% increase 18.18% increase 36.36% increase 36.36% decrease 36.36% increase 18.18% increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Motors for fans and pumps are selected in the rpm range 1440 to 2880. 375 to 500. 500 to 720. 720 to 920. 1440 to 2880. 375 to 500. 500 to 720. 720 to 920. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC Shunt Motor if the load current increases keeping the terminal voltage constant, then flux will any of the above. remain constant. decrease. increase. any of the above. remain constant. decrease. increase. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The demagnetising component of armature reaction in a DC generator reduces inter poles flux density. increases armature speed. results in sparking trouble. reduces generator emf. reduces inter poles flux density. increases armature speed. results in sparking trouble. reduces generator emf. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor power output of 3-phase induction motor is 15 KW. The rotor copper losses at a slip of 4% will be 650 W 600 W 625 W 700 W 650 W 600 W 625 W 700 W ANSWER DOWNLOAD EXAMIANS APP