Electrical Machines For very sensitive and wide speed control, the preferable control method is Multiple voltage control. Field control. Armature control. Ward-Leonard control. Multiple voltage control. Field control. Armature control. Ward-Leonard control. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Tap changer is generally provided in current transformer. voltage transformer. earthing transformer. power transformer. current transformer. voltage transformer. earthing transformer. power transformer. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The DC generator runs at a speed of 1000 rpm and flux per pole is 0.2 Wb, number of poles are 2 the winding is wave wound and having 480 conductors. The critical speed is 1200 rpm. Then the generated emf ( Eg ) 1500 Volt. 0 Volt. 2000 Volt. 1600 Volt. 1500 Volt. 0 Volt. 2000 Volt. 1600 Volt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 3, 4, 5 2, 3, 6 2, 4, 5, 6 1, 2, 5 3, 4, 5 2, 3, 6 2, 4, 5, 6 1, 2, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor speed of an induction motor is given by Nr = 120f / p × (1-s). Ns = 120f /p × ( 1 - r). None of these Ns = 120f / p × ( 1 - s ). Nr = 120f / p × (1-s). Ns = 120f /p × ( 1 - r). None of these Ns = 120f / p × ( 1 - s ). ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The heat generated in the transformer is dissipated mainly by radiation. conduction. convection. All of these radiation. conduction. convection. All of these ANSWER DOWNLOAD EXAMIANS APP