Electrical Machines For the purpose of starting an induction motor, star/delta switch is an equivalent to auto transformer of ratio 66.3% 57.7% 33.3% 50% 66.3% 57.7% 33.3% 50% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the frequency of a alternator, if P = number of poles and N = revolution made per second? 120P / N Hz. 120N / P Hz. PN / 2 Hz. 120 / PN Hz. 120P / N Hz. 120N / P Hz. PN / 2 Hz. 120 / PN Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The change in speed of a DC generator due to increased load is corrected by increasing armature cooling. increasing armature resistance. increasing terminal voltage. increasing input power of the prime mover. increasing armature cooling. increasing armature resistance. increasing terminal voltage. increasing input power of the prime mover. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous generator, if mechanical input is increased with constant excitation, the load angle will None of these increase either increase or decrease decrease None of these increase either increase or decrease decrease ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor winding for a 3-phase slip-ring induction motor having delta-connected stator must be connected in delta or star according to need. delta. star. None of these delta or star according to need. delta. star. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 400 V, 50 Hz, 30 Hp, three phase IM is drawing 50 A current at 0.8 p.f lagging. The stator and rotor copper losses are 1.5 KW and 900 W respectively. The friction and windage losses are 1050 W and core losses are 1200 W. The air gap power of the motor will be 23.06 kW. 26.21 kW. 24.11 kW. 25 kW. 23.06 kW. 26.21 kW. 24.11 kW. 25 kW. ANSWER DOWNLOAD EXAMIANS APP