Electrical Machines Field weakening control method is used for the _________ ? above rated speed below rated speed None of these both A and B above rated speed below rated speed None of these both A and B ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Brushes are always placed on--------------- , in order to achieve sparkles commutation? None of these either GNA or MNA GNA MNA None of these either GNA or MNA GNA MNA ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Slip speed is the half of the sum of synchronous and rotor speeds. sum of synchronous and rotor speeds. difference of synchronous speed and actual rotor speed. difference of actual rotor speed and synchronous speed. half of the sum of synchronous and rotor speeds. sum of synchronous and rotor speeds. difference of synchronous speed and actual rotor speed. difference of actual rotor speed and synchronous speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider a separately excited DC motor. If the field current is increased while the armature terminal voltage is held constant, then speed of the motor None of these. Increase. Remains same. Decrease. None of these. Increase. Remains same. Decrease. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following factors improve commutation in a dc machine ? 1. High contact resistance of brushes 2. High inductance of the coils undergoing commutation 3. Shifting of brushes in the direction of rotation for a generator and in the opposite direction For a motor 4. Narrow width for the commutation bars Select the correct answer using the codes given below : Codes : 2, 3 and 4 1 and 3 1, 2, and 3 1, 2 and 4 2, 3 and 4 1 and 3 1, 2, and 3 1, 2 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The breakdown torque of a synchronous motor varies as 1/V V² 1/V² applied voltage V 1/V V² 1/V² applied voltage V ANSWER DOWNLOAD EXAMIANS APP
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