Electrical Machines The current drawn by a 220 V DC series motor of armature resistance 0.5Ω and back back emf 200 V is 44 A. 40 A. 400 A. 440 A. 44 A. 40 A. 400 A. 440 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a loaded DC generator, if the brushes are given a shift from the interpolar axis in the direction of rotation, then the commutation will improve with fall of terminal voltage. improve with rise in terminal voltage. deteriorate with fall of terminal voltage. deteriorate with rise in terminal voltage. improve with fall of terminal voltage. improve with rise in terminal voltage. deteriorate with fall of terminal voltage. deteriorate with rise in terminal voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To have sparkless commutation, the armature reaction effect in a DC machine is neutralized by compensating winding and commutating poles. shifting the brush axis from GNA to MNA. increasing field excitation. fixing the brush axis inline with the pole axis. compensating winding and commutating poles. shifting the brush axis from GNA to MNA. increasing field excitation. fixing the brush axis inline with the pole axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole 50 Hz induction motor is running at 1470 rpm. Find the speed of stator magnetic field with respect to rotor? zero 1500 rpm 1470 rpm 30 rpm zero 1500 rpm 1470 rpm 30 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Direct axis reactance is defined as the ratio of Vmin to Imax Vmin to Imin Vmax to Imax Vmax to Imin Vmin to Imax Vmin to Imin Vmax to Imax Vmax to Imin ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : Interpoles in dc machines 1. reducearmature reaction effects in the interpolar region 2. have the same dimension as main polls 3. have their windings connected in series with the armature 4. have same number of turns as the armature 5. have the polarity same as that of the main pole ahead in a motor From these, the correct statements are 1, 3 and 5 1, 2, 3 and 5 1 and 3 1, 2 and 3 1, 3 and 5 1, 2, 3 and 5 1 and 3 1, 2 and 3 ANSWER DOWNLOAD EXAMIANS APP
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