Electrical Machines If the applied voltage of a DC motor is 230 V, then back emf, for maximum power developed is 230 V. 115 V. 460 V. 200 V. 230 V. 115 V. 460 V. 200 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a seperately excited DC Motor if field current is increased, it will Reduce starting torque. Increase speed Reduce armature heating. Increase acceleration duration. Reduce starting torque. Increase speed Reduce armature heating. Increase acceleration duration. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines φA 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 speed when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 970 RPM 960 RPM 940 RPM 920 RPM 970 RPM 960 RPM 940 RPM 920 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The stator frame in an induction motor is used to ventilate the armature. hold armature stamping in position. protect the whole machine. provide return path for the flux. ventilate the armature. hold armature stamping in position. protect the whole machine. provide return path for the flux. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To achieve spark less commutation brushes of DC generator are rocked ahead so as to bring them just behind the magnetic neutral axis. None of these in magnetic neutral axis. just ahead of magnetic neutral axis. just behind the magnetic neutral axis. None of these in magnetic neutral axis. just ahead of magnetic neutral axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For same HP rating and full load speed which of following motor has poor starting torque? Cummulative compound. Shunt. Series. Differently compounded. Cummulative compound. Shunt. Series. Differently compounded. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS