Electrical Machines A separately excited DC motor has an armature resistance of 0.5 Ohm. The supply voltage is 250V. Armature current is 20A and the speed of rotation is 1500 rpm. Find the torque developed? Zero 15.28 Nm 15.6 Nm 16.55 Nm Zero 15.28 Nm 15.6 Nm 16.55 Nm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 3, 5 1, 2, 5 1, 2, 6 1, 4, 6 1, 3, 5 1, 2, 5 1, 2, 6 1, 4, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a dc machine shunt resistance and armature resistance values are low and high high and high low and low high and low low and high high and high low and low high and low ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Open circuit test on transformer gives copper loss hysteresis loss both 1and 2 eddy current loss copper loss hysteresis loss both 1and 2 eddy current loss 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 identical as 4% from no load to full load. Consider the governors operating at 50Hz on no load. What is the operating frequency, if the load is 600 MW? 50 Hz 45 HZ 48 Hz 48.5 Hz 50 Hz 45 HZ 48 Hz 48.5 Hz 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? None of these 200 MW and 400MW generator 1 gets over load generator 2 gets over load None of these 200 MW and 400MW generator 1 gets over load generator 2 gets over load ANSWER DOWNLOAD EXAMIANS APP