Electrical Machines An ideal synchronous motor has no starting torque because rotor is made up of salient poles. relative velocity between stator and rotor mmf’s is not zero. rotor winding is highly reactive. relative velocity between the stator and rotor mmf’s is zero. rotor is made up of salient poles. relative velocity between stator and rotor mmf’s is not zero. rotor winding is highly reactive. relative velocity between the stator and rotor mmf’s is zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A slip ring Induction motor runs at 290 rpm at full load, when connected to 50 Hz supply. Determine the number of poles and slip. P = 20, s = 3.33 %. P = 60, s = 0.96 %. P = 50, s = 4.43 %. P = 40, s = 5.79 %. P = 20, s = 3.33 %. P = 60, s = 0.96 %. P = 50, s = 4.43 %. P = 40, s = 5.79 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC generator will not build up voltage any one of above. due to wrong direction of rotation. if it has lost residual magnetism. if field resistance is more than critical resistance. any one of above. due to wrong direction of rotation. if it has lost residual magnetism. if field resistance is more than critical resistance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In one 132 / 33 kV transformer the LV resistance is 0.02 per unit. The resistance referred to HV side is 0.01 pu. 0.02 pu. 0.08 pu. 0.16 pu. 0.01 pu. 0.02 pu. 0.08 pu. 0.16 pu. 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. 470 rpm. 240 rpm. 450 rpm. 540 rpm. 470 rpm. 240 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V dc machine has an armature resistance of 1Ω.If the full-load current is 20 A, the differenc in the induced voltages when the machine is running as a motor and as a generator is 40 V 50 V 20 V zero 40 V 50 V 20 V zero ANSWER DOWNLOAD EXAMIANS APP