Electrical Machines A dc shunt motor runs at a no-load speed of 1140 rpm. At full load, armature reaction weakens the main flux by 5% whereas the armature circuit voltage drops by 10%. The motor full-load speed in rpm is 1203 1200 1000 1080 1203 1200 1000 1080 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Commutation in a DC machine may be explained as a process how alternate flux affects the main field flux. by virtue of which emf is induced in the armature conductors. by which electric current in a coil is reversed. in which magnetic field is set up. how alternate flux affects the main field flux. by virtue of which emf is induced in the armature conductors. by which electric current in a coil is reversed. in which magnetic field is set up. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An inverted V curve of synchronous motor shows variation of power factor and DC excitation at constant load. supply voltage and field current at constant excitation. supply voltage and excitation current at constant load. power factor and supply voltage during hunting. power factor and DC excitation at constant load. supply voltage and field current at constant excitation. supply voltage and excitation current at constant load. power factor and supply voltage during hunting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two DC series motors are connected in series and are driving the same mechanical load. If the motors are now connected in parallel the speed will become double. 4 times. one fourth. half. double. 4 times. one fourth. half. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If in a sub – station there is one 132 / 33 kV transformer whose secondary is connected with primary of one 33 / 11 kV transformer, the total transformation ratio of the sub – station will be, 12. 7. 3. 4. 12. 7. 3. 4. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc machine, the demagnetizing effect of armature reaction is due to non-sinusoidal nature of armature mmf magnetic saturation in half of the field pole component of armature mmf along field axis uneven air-gap length non-sinusoidal nature of armature mmf magnetic saturation in half of the field pole component of armature mmf along field axis uneven air-gap length ANSWER DOWNLOAD EXAMIANS APP
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