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 750rpm zero speed 1500 rpm 1000 rpm 750rpm zero speed 1500 rpm 1000 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc generator operating on load with its brushes on the geometrical neutral axis (GNA), the magnetic neutral axis (MNA) is shifted in the direction of rotation. Now, if the brushes are given a lead of 90° (electrical), then the MNA will shift forward by more than 90° coincide with the GNA shift forward by less than 90° shift forward by 90° shift forward by more than 90° coincide with the GNA shift forward by less than 90° shift forward by 90° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The leakage reactance of a 3-phase alternator is determined by performing zero power factor and slip tests. short circuit and slip tests. open circuit and zero power factor tests. open circuit and short circuit tests. zero power factor and slip tests. short circuit and slip tests. open circuit and zero power factor tests. open circuit and short circuit tests. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 400 V, 50 Hz, 30 Hp, three phase IM is drawing 50 A current at 0.8 p.f lagging. The stator and rotor copper losses are 1.5 KW and 900 W respectively. The friction and windage losses are 1050 W and core losses are 1200 W. The air gap power of the motor will be 24.11 kW. 26.21 kW. 25 kW. 23.06 kW. 24.11 kW. 26.21 kW. 25 kW. 23.06 kW. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V dc machine has an armature resistance of 1Ω.If the full-load current is 20 A, the differenc in the induced voltages when the machine is running as a motor and as a generator is 50 V 40 V 20 V zero 50 V 40 V 20 V zero ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage of a certain transformer is increased by 50% and the frequency is reduced by 50%, the maximum flux density will (assuming that the magnetic circuit remains unsaturated) changes to 1.5 times the original value remain the same as the original changes to three times the original value changes to 0.5 times the original value changes to 1.5 times the original value remain the same as the original changes to three times the original value changes to 0.5 times the original value ANSWER DOWNLOAD EXAMIANS APP