Electrical Machines Which of the following DC Motor is used in paper machines? DC compound motor. Separately excited DC motor. DC Shunt motor. DC series motor. DC compound motor. Separately excited DC motor. DC Shunt motor. DC series motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A cumulatively compounded dc motor delivers rated load power at rated speed. If the series field is short-circuited, then Ia increases and ωm decreses Ia remains constant but ωm increase both decrese both armature current Ia and speed ωm increase Ia increases and ωm decreses Ia remains constant but ωm increase both decrese both armature current Ia and speed ωm increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 230 V, 50 Hz, 4 pole single phase induction motor is rotating in the clockwise ( forward ) direction at a speed of 1425 rpm. If the rotor resistance at standstill is 7.8 Ω. Then the effective rotor resistance in the backward branch of the equivalent circuit will be 4 Ω. 8 Ω. 2 Ω. 10 Ω. 4 Ω. 8 Ω. 2 Ω. 10 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The net voltage across the armature resistance at the time of plugging will be 6 V 234 V 240 V 474 V 6 V 234 V 240 V 474 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In 3 - Φ induction motor some times copper bars are placed deep in the rotor to improve efficiency. improve starting torque. improve power factor. reduce copper loss. improve efficiency. improve starting torque. improve power factor. reduce copper loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding dc machines : 1. possible resistance of shunt-field winding is 1 Ω 2. possible resistance of series-field winding is 1 Ω 3. electrographite brushes are used for 230 V, 10 A machines 4. Copper-graphite brushes are used for 230 V, 10 A machines 5. Possible armature-circuit resistance is 1 Ω From these, the correct statements are 2, 4 ,5 2, 3 , 5 1, 4 1, 3, 5 2, 4 ,5 2, 3 , 5 1, 4 1, 3, 5 ANSWER DOWNLOAD EXAMIANS APP
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