Electrical Machines Field weakening control method is used for the _________ ? above rated speed both A and B below rated speed None of these above rated speed both A and B below rated speed None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole, 3-phase induction motor is running at 4% slip at full load. If the speed of the motor is 720 rpm, the supply frequency is 60 Hz 25 Hz 50 Hz 40 HZ 60 Hz 25 Hz 50 Hz 40 HZ ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements about commutating poles which are fitted on most large dc Shunt motors: 1. The commutating poles are placed in the geometric neutral plane and their number is usually Equal to the number of main poles 2. The winding on the commutating poles is connected in series with the shunt-field winding on the main poles 3. The polarity of the commutating pole must be that of the next pole further ahead 4. The commutating poles neutralize the reactance voltage produced in the coil undergoing Commutation. Of these statements, 1, 2 and 3 are correct 1, 2 and 4 are correct 2, 3 and 4 are correct 1 and 4 are correct 1, 2 and 3 are correct 1, 2 and 4 are correct 2, 3 and 4 are correct 1 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of rotating magnetic field of 8 pole 50 Hz induction motor is 1000 rpm 3000 rpm 1500 rpm 750 rpm 1000 rpm 3000 rpm 1500 rpm 750 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The supply voltage to an induction motor is reduced by 10%. By what percentage, approximately, will the maximum torque decrease? 10% 19% 5% 40% 10% 19% 5% 40% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are 4% and 5% from no load to full load. Consider the governors operating at 50Hz on no load. How will the machine share, if the load is 600 MW? generator 2 gets over load None of these generator 1 gets over load 200 MW and 400MW generator 2 gets over load None of these generator 1 gets over load 200 MW and 400MW ANSWER DOWNLOAD EXAMIANS APP