Electrical Machines If a DC Series motor is connected across an AC supply it will burn. not run. run at lower speed. run at normal speed. burn. not run. run at lower speed. run at normal speed. 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 600 W 650 W 625 W 700 W 600 W 650 W 625 W 700 W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If we increase the rotor reactance value, the maximum torque will None of these not changed increase decrease None of these not changed increase decrease ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC Shunt Motor having shunt field resistance of 250 Ω and armature resistance of 0.5 Ω is connected to 250 V supply and load current of 21 A. What is the back emf generated ? 150 V. 240 V. 230 V. 210 V 150 V. 240 V. 230 V. 210 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If starting current of a 3 - Φ induction motor is 5 times the rated current, while rated slip is 4 %, then ratio of starting torque to full load torque is 0.4. 1. 0.8. 0.6. 0.4. 1. 0.8. 0.6. 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 1, 2, 5 3, 4, 5 2, 4, 5, 6 2, 3, 6 1, 2, 5 3, 4, 5 2, 4, 5, 6 2, 3, 6 ANSWER DOWNLOAD EXAMIANS APP