Electrical Machines Unbalance 3 - Φ stator currents cause heating of rotor. All of these vibrations. double frequency currents in the rotor. heating of rotor. All of these vibrations. double frequency currents in the rotor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor speed of an induction motor is given by Ns = 120f / p × ( 1 - s ). Nr = 120f / p × (1-s). None of these Ns = 120f /p × ( 1 - r). Ns = 120f / p × ( 1 - s ). Nr = 120f / p × (1-s). None of these Ns = 120f /p × ( 1 - r). ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If peak value of phase mmf is F max , then peak value of the rotating field caused by three phase is (1/2)Fmax. Fmax. (3/2)Fmax. 3Fmax. (1/2)Fmax. Fmax. (3/2)Fmax. 3Fmax. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a single phase capacitor start induction motor which of the following is valid? Direction of rotation cannot be changed. Rotation can be changed by reversing main winding terminals. None of these. Rotation can be changed by interchanging supply terminals. Direction of rotation cannot be changed. Rotation can be changed by reversing main winding terminals. None of these. Rotation can be changed by interchanging supply terminals. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A generator may loose residual magnetism due to over excitation. vibrations. any of these. heating. over excitation. vibrations. any of these. heating. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm. Find the rotor efficiency? 92% 95% 96% 94% 92% 95% 96% 94% ANSWER DOWNLOAD EXAMIANS APP