Electrical Machines Brushes are always placed on--------------- , in order to achieve sparkles commutation? GNA MNA either GNA or MNA None of these GNA MNA either GNA or MNA None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In synchronous generator V curve is drawn between field current on X-axis and armature current on Y-axis. field current on Y-axis and armature current on X-axis. either of these. field current on X-axis and power factor on Y-axis. field current on X-axis and armature current on Y-axis. field current on Y-axis and armature current on X-axis. either of these. field current on X-axis and power factor on Y-axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by a DC motor at the time of starting is Zero. Very high. Normal. Very low. Zero. Very high. Normal. Very low. 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%. 82.5% 78.5% 67.5% 72.5% 82.5% 78.5% 67.5% 72.5% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature reaction mmf in a DC machines has a form of rectangular. trapezoidal. triangular. sinusoidal. rectangular. trapezoidal. triangular. sinusoidal. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An 8 pole DC generator has 500 armature conductors and useful flux per pole of 0.065 Wb. What will be the emf generated if it is lap connected and runs at 1000 rpm. What must be the speed at which it is driven to produce the same emf if it is wave wound? 2166.67V, 230 rpm. 2166.67V, 270 rpm. 541.67V, 200 rpm. 541.67V, 250 rpm. 2166.67V, 230 rpm. 2166.67V, 270 rpm. 541.67V, 200 rpm. 541.67V, 250 rpm. ANSWER DOWNLOAD EXAMIANS APP
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