Electrical Machines Compensating windings are used in DC generators to neutralize the cross magnetizing effect of the armature reaction. None of these to provide path for the circulation of cooling air. mainly to reduce the eddy currents by providing local short circuit. to neutralize the cross magnetizing effect of the armature reaction. None of these to provide path for the circulation of cooling air. mainly to reduce the eddy currents by providing local short circuit. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In the V curve shown in figure below for a synchronous motor, the parameter of Y and X coordinates are, respectively Power factor and field current. Armature current and field current. Armature current and torque. Torque and field current. Power factor and field current. Armature current and field current. Armature current and torque. Torque and field current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To achieve spark less commutation brushes of DC generator are rocked ahead so as to bring them just ahead of magnetic neutral axis. None of these just behind the magnetic neutral axis. in magnetic neutral axis. just ahead of magnetic neutral axis. None of these just behind the magnetic neutral axis. in magnetic neutral axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In 3 - Φ induction motor some times copper bars are placed deep in the rotor to improve starting torque. reduce copper loss. improve power factor. improve efficiency. improve starting torque. reduce copper loss. improve power factor. improve efficiency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For satisfactory performance of 3-phase 480V, 60 Hz induction motor, the supply voltage at 50 Hz should be equal to 400 V. 420 V. 480 V. 350 V. 400 V. 420 V. 480 V. 350 V. 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 external resistance to be added in the armature circuit to limit the armature current to 125% of its rated value is 15.9 Ω 31.9 Ω 15.1 Ω 31.1 Ω 15.9 Ω 31.9 Ω 15.1 Ω 31.1 Ω ANSWER DOWNLOAD EXAMIANS APP