Electrical Machines A 3-phase slip ring induction motor is wound for 4 poles on stator and 6 poles on the rotor. When 3-phase balanced voltage source at 50 Hz is applied, it will run at 1500 rpm zero speed 750rpm 1000 rpm 1500 rpm zero speed 750rpm 1000 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines During hunting of a synchronous motor damper bar develops torque. harmonic are developed in the armature circuit. field excitation increases. negative phase sequence currents are generated. damper bar develops torque. harmonic are developed in the armature circuit. field excitation increases. negative phase sequence currents are generated. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 1, 4 1, 3 2, 3 2, 4 1, 4 1, 3 2, 3 2, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Magnetic field of a DC generator is produced by what? None of the options. Both B and C. Permanent magnets. Electromagnets. None of the options. Both B and C. Permanent magnets. Electromagnets. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an additional resistance is connected in series with a DC series motor operating at rated speed, the speed of the motor will Oscillate around the normal speed. Increase. Reduce. Remain unaltered. Oscillate around the normal speed. Increase. Reduce. Remain unaltered. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor is suitable for frequent starting and stoppings? All of these Capacitor start capacitor run motor Capacitor start motor Resistance split phase motor All of these Capacitor start capacitor run motor Capacitor start motor Resistance split phase motor ANSWER DOWNLOAD EXAMIANS APP