Electrical Machines The field divertor resistance for a DC series motor is of order of 0.1 Ω 100 Ω 50 Ω 10 Ω 0.1 Ω 100 Ω 50 Ω 10 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a given torque, reducing diverter resistance of a DC series motor causes decrease in speed but armature current remains the same. decrease in speed demanding less armature current. increase in speed but armature currnet remains the same. increase in speed demanding more armature current. decrease in speed but armature current remains the same. decrease in speed demanding less armature current. increase in speed but armature currnet remains the same. increase in speed demanding more armature current. 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 coincide with the GNA shift forward by 90° shift forward by less than 90° shift forward by more than 90° coincide with the GNA shift forward by 90° shift forward by less than 90° shift forward by more than 90° 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. 1600 Volt. 2000 Volt. 1500 Volt. 0 Volt. 1600 Volt. 2000 Volt. 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% 82.5% 67.5% 78.5% 72.5% 82.5% 67.5% 78.5% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are the methods to reduce the armature reaction and its effects? pole chamfering pole stacking All of these compensating winding pole chamfering pole stacking All of these compensating winding ANSWER DOWNLOAD EXAMIANS APP