Electrical Machines In a DC machine, which of these parameters remain the same whether it runs as a DC motor or a DC generator? Can not be determined. Induced emf. Armature current. Mechanical power. Can not be determined. Induced emf. Armature current. Mechanical power. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 6 pole, 50 Hz IM is running at a full load speed of 980 rpm. If it delivers an air gap power of 98000 Watt, calculate the rotor ohmic loss? 980 Watt. 1920 Watt. 1960 Watt. 1800 Watt. 980 Watt. 1920 Watt. 1960 Watt. 1800 Watt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor when the length of the air gap is increased, the magnetizing current of the motor increases while the short circuit current __________________. decreased. remains unchanged. increased. kept constant to certain value. decreased. remains unchanged. increased. kept constant to certain value. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the efficiency when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 72.5% 78.5% 67.5% 82.5% 72.5% 78.5% 67.5% 82.5% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage to a dc machine is 230 V, then the back emf, for maximum power developed, is 230 V 200 V 115 V 460 V 230 V 200 V 115 V 460 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a three phase slip-ring induction motor, brushes are connected to external star-connected resistors. equalizing coils. 3 - Φ AC supply. DC supply. external star-connected resistors. equalizing coils. 3 - Φ AC supply. DC supply. ANSWER DOWNLOAD EXAMIANS APP
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