Electrical Machines Copper brushes in DC machine are used None of these in both of above cases. where low voltage and high currents are involved. where high voltage and low current. None of these in both of above cases. where low voltage and high currents are involved. where high voltage and low current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To have sparkless commutation, the armature reaction effect in a DC machine is neutralized by increasing field excitation. shifting the brush axis from GNA to MNA. fixing the brush axis inline with the pole axis. compensating winding and commutating poles. increasing field excitation. shifting the brush axis from GNA to MNA. fixing the brush axis inline with the pole axis. compensating winding and commutating poles. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Conservator tank is used to act as an oil storage. None of these for better cooling of transformer. to take up the expansion of oil due to temperature rise. to act as an oil storage. None of these for better cooling of transformer. to take up the expansion of oil due to temperature rise. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The sparking at the the brushes, in a DC machines is due to armature reaction. reactance voltage. high resistance of carbon brushes. presence of commutator. armature reaction. reactance voltage. high resistance of carbon brushes. presence of commutator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The no load and full load speed of DC motor are 1400 rpm and 1200 rpm respectively. What is the percentage speed regulation of the motor ? 18.25%. 16.67%. 14.28%. 15.30%. 18.25%. 16.67%. 14.28%. 15.30%. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An electric motor with constant output power will have a torque speed characteristics in the form of a Straight line through the origin. Straight line parallel to the speed axis. Rectangular hyperbola Circle about the origin. Straight line through the origin. Straight line parallel to the speed axis. Rectangular hyperbola Circle about the origin. ANSWER DOWNLOAD EXAMIANS APP