Electrical Machines If peak value of phase mmf is F max , then peak value of the rotating field caused by three phase is Fmax. (1/2)Fmax. (3/2)Fmax. 3Fmax. Fmax. (1/2)Fmax. (3/2)Fmax. 3Fmax. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which motor cannot be started on no load? series motors both B and C shunt motors cumulative compound motors series motors both B and C shunt motors cumulative compound motors ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Addition of 0.3 % to 4.5 % silicon to iron increases the hysteresis loss. None of these increases the electrical resistivity of iron. reduces the saturation magnetization. increases the hysteresis loss. None of these increases the electrical resistivity of iron. reduces the saturation magnetization. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of following DC motors will have percentage increase of input current for the same percentage increase in torque? Shunt. Cummulative compound. Series. Differntical compound. Shunt. Cummulative compound. Series. Differntical compound. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 2, 3 1, 4 2, 4 1, 3 2, 3 1, 4 2, 4 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 12 pole, 600 V, 50 Hz star connected IM has rotor resistance and stand still resistance of 0.03 Ω and 0.5 Ω respectively. The speed of maximum torque will be 450 rpm. 540 rpm. 240 rpm. 470 rpm. 450 rpm. 540 rpm. 240 rpm. 470 rpm. ANSWER DOWNLOAD EXAMIANS APP