Electrical Machines A 3-phase, 2 pole, 12 slot synchronous machine is operating at synchronous speed. Find the slot angle? 18° 20° 30° 60° 18° 20° 30° 60° 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 ∝ 1/(φf) E ∝ f/φ E ∝ φ/f E ∝ φf E ∝ 1/(φf) E ∝ f/φ E ∝ φ/f E ∝ φf ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC Shunt Motor having armature resistance of 0.5 Ω and 2 A armature current at no-load, when the armature current is changed to 20 A at loaded condition the speed is 1000 r.p.m. What is the speed at no-load? 1130 r.p.m. 4575.4 r.p.m. 1037.5 r.p.m. none of above. 1130 r.p.m. 4575.4 r.p.m. 1037.5 r.p.m. none of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is/are the necessary conditions for parallel operation of alternators? Both 1and 2 Frequency should be same Speed of alternators should be same Terminal voltage is same Both 1and 2 Frequency should be same Speed of alternators should be same Terminal voltage is same ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor having 8 poles runs at 727.5 rpm. If the supply frequency is 50Hz, the emf in the rotor will have a frequency of 2.5Hz 1.5Hz 48.5Hz 51.5Hz 2.5Hz 1.5Hz 48.5Hz 51.5Hz ANSWER DOWNLOAD EXAMIANS APP