Electrical Machines Considering a galvanometer is connected to the rotor of a 3 - Φ, 4 pole, 50 Hz IM and is making 130 oscillations in a minute, then calculate the rotor speed? 1440. 1450. 1435. 1500. 1440. 1450. 1435. 1500. 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 = N1 / N2. E1 / E2 = 1. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For the purpose of starting an induction motor, star/delta switch is an equivalent to auto transformer of ratio 50% 66.3% 33.3% 57.7% 50% 66.3% 33.3% 57.7% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor speed of an induction motor is given by Nr = 120f / p × (1-s). Ns = 120f / p × ( 1 - s ). None of these Ns = 120f /p × ( 1 - r). Nr = 120f / p × (1-s). Ns = 120f / p × ( 1 - s ). None of these Ns = 120f /p × ( 1 - r). ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To get the speed of DC motor is more than normal without wastage of electrical energy _____________ is used. Rheostatic control. None of above. Ward Leonard control. Any of above method. Rheostatic control. None of above. Ward Leonard control. Any of above method. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Example of double excited machine is Synchronous motor. Both are correct. None of these DC Shunt Motor Synchronous motor. Both are correct. None of these DC Shunt Motor ANSWER DOWNLOAD EXAMIANS APP