Electrical Machines If the handle of a three point starter goes to back to OFF position, it may be due to zero or very low voltage supply. all of these. over load. high filed circuit resistance. zero or very low voltage supply. all of these. over load. high filed circuit resistance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if φ is the flux per pole and f is the frequency of the emf induced E then E ∝ φ/f E ∝ φf E ∝ f/φ E ∝ 1/(φf) E ∝ φ/f E ∝ φf E ∝ f/φ E ∝ 1/(φf) ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is done in speed control of DC motor by field flux control? Inserting an additional resistance in the field circuit. Any of above. Inserting resistance to armature circuit and field circuit. Inserting an additional resistance in the armature circuit. Inserting an additional resistance in the field circuit. Any of above. Inserting resistance to armature circuit and field circuit. Inserting an additional resistance in the armature circuit. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Autotransformer makes effective saving on copper and copper losses, when its transformation ratio is equal to less than one. greater than one. approx to one. very low less than one. greater than one. approx to one. very low ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Induction motors provided with open slots have higher efficiency. leading power factor. less breakdown torque. more breakdown torque. higher efficiency. leading power factor. less breakdown torque. more breakdown torque. 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 = N1kw1 / N2kw2. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = 1. E1 / E2 = N1 / N2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = 1. E1 / E2 = N1 / N2. ANSWER DOWNLOAD EXAMIANS APP