Electrical Machines In a DC machine, which of these parameters remain the same whether it runs as a DC motor or a DC generator? Mechanical power. Armature current. Induced emf. Can not be determined. Mechanical power. Armature current. Induced emf. Can not be determined. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 4, 6 1, 2, 6 1, 2, 5 1, 3, 5 1, 4, 6 1, 2, 6 1, 2, 5 1, 3, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Select the motor that should not be started on no load? Compound motor. Shunt motor. Brushless DC motor. Series motor. Compound motor. Shunt motor. Brushless DC motor. Series motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is/are the necessary conditions for voltage build up in self excited generator? Poles should contain residual flux. All of these Field winding should be properly connected to armature winding. Field winding resistance should be less than critical resistance. Poles should contain residual flux. All of these Field winding should be properly connected to armature winding. Field winding resistance should be less than critical resistance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In double cage induction motor, the inner cage offers low resistance and high reactance. high resistance and low reactance. high resistance and high reactance. low resistance and low reactance. low resistance and high reactance. high resistance and low reactance. high resistance and high reactance. low resistance and low reactance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ IM with line frequency f1 and winding factor kw1 and kw2 for stator and rotor respectively the ratio of per phase stator winding emf E1 to per phase rotor winding emf E2 at standstill is given by E1 / E2 = N1 / N2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = 1. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1 / N2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = 1. E1 / E2 = f1kw1 / f2kw2. ANSWER DOWNLOAD EXAMIANS APP